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Vol 57 Issue 2

April 2013

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E-ISSN 1471-0676

A quarterly journal of research on the

science and technology of the platinum

group metals and developments in their

application in industry

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E-ISSN 1471-0676 • Platinum Metals Rev., 2013, 57, (2), 85•

Editorial Team: Jonathan Butler (Publications Manager); Sara Coles (Assistant Editor); Ming Chung (Editorial Assistant);Keith White (Principal Information Scientist)

Platinum Metals Review, Johnson Matthey Plc, Orchard Road, Royston, Hertfordshire SG8 5HE, UKEmail: [email protected]

Platinum Metals ReviewA quarterly journal of research on the platinum group metals

and developments in their application in industryhttp://www.platinummetalsreview.com/

APRIL 2013 VOL. 57 NO. 2

Contents Johnson Matthey and Alfa Aesar Support Academic Research 86 An editorial by Sara Coles

Platinum-Based and Platinum-Doped Layered Superconducting Materials: 87 Synthesis, Properties and Simulation By Alexander L. Ivanovskii

CAT4BIO Conference: Advances in Catalysis for Biomass Valorization 101

A conference review by Eleni Heracleous and Angeliki Lemonidou

Johnson, Matthey and the Chemical Society 110 By William P. Griffi th

SAE 2012 World Congress 117 A conference review by Timothy V. Johnson

“Complex-shaped Metal Nanoparticles: 123 Bottom-Up Syntheses and Applications” A book review by Laura Ashfi eld

Crystallographic Properties of Ruthenium 127 By John W. Arblaster

“Polymer Electrolyte Membrane and 137 Direct Methanol Fuel Cell Technology” A book review by Bruno G. Pollet

Kunming–PM2012 143

A conference review by Mikhail Piskulov and Carol Chiu

Publications in Brief 148

Abstracts 151

Patents 154

Final Analysis: NOx Emissions Control for Euro 6 157 By Jonathan Cooper and Paul Phillips


http://dx.doi.org/10.1595/147106713X665067 •Platinum Metals Rev., 2013, 57, (2), 86•

Editorial

Johnson Matthey and Alfa Aesar Support Academic ResearchAs many of our readers are no doubt aware, Alfa

Aesar is Johnson Matthey’s catalogue chemicals

business. As well as supplying research chemicals

to the fi ne chemicals and pharmaceuticals

industries, Alfa Aesar also supplies universities

and can deliver at any scale from bench to

pilot plant and through to commercial scale

production (1).

Platinum Metals Review has now teamed up

with Alfa Aesar to administer the “Johnson Matthey

Alfa Aesar Research Chemicals Scheme”, formerly

known as the “Loans Scheme”. Since the early years

of the 20th century, Johnson Matthey has used this

scheme to support fundamental research centred on

the platinum group metals (pgms) (2). Academics

and university groups can apply to receive small

amounts of pgm salts for use in their research, with a

focus on novel applications which may have future

commercial potential.

The scheme is currently well-subscribed. In the

past year we have supported projects in diverse areas

including anticancer drugs, asymmetric catalysis,

biomass conversion, nanoparticles, pharmaceuticals,

photovoltaics and renewable energy.

We are delighted to formally announce our

partnership with Alfa Aesar who from April 2013

will be supplying the chemicals from their stocks.

We look forward to working with our colleagues at

Alfa Aesar.

SARA COLES, Assistant Editor

Platinum Metals Review

References1 Alfa Aesar, A Johnson Matthey Company:

http://www.alfa.com/

2 D. T. Thompson, Platinum Metals Rev., 1987, 31, (4), 171

Contact InformationJohnson Matthey Precious Metals MarketingOrchard Road Royston HertfordshireSG8 5HEUK

Email: [email protected]

“PGMs in the Lab”From the next issue of Platinum Metals Review, in

July 2013, we will feature a new section called “PGMs

in the Lab” in which we will profi le one of the many

researchers whose work has benefi ted from the

support of Johnson Matthey and Alfa Aesar. This work

has expanded the boundaries of pgms research and

we hope that many new applications for the pgms

will arise from this exciting collaborative approach.

Look out for the new section and see if it inspires you

to try some new collaborations of your own.

Finally don’t forget that we are always interested

to hear from you about your research into new

areas of application for the pgms. So if you have

some new pgm research to report, a book that you

would like reviewed, or a conference that you have

organised or attended, please contact us at the

above address.

•Platinum Metals Rev., 2013, 57, (2), 87–100•


Platinum-Based and Platinum-Doped Layered Superconducting Materials: Synthesis, Properties and SimulationExperimental and theoretical results for newest group of high-temperature superconductors

http://dx.doi.org/10.1595/147106713X663780 http://www.platinummetalsreview.com/

By Alexander L. Ivanovskii

Institute of Solid State Chemistry, Ural Branch of the Russian Academy of Sciences, 620990 Ekaterinburg, Russia


In 2011, the newest group of layered high-temperature

superconductors were discovered: platinum-based

quaternary 10-4-8 (Ca10(Pt4As8)(Fe2As2)5) and 10-3-8

((CaFe1–xPtxAs)10Pt3As8) phases with superconducting

transition temperatures (TC) up to 35–38 K. Intensive

studies have been carried out to investigate their

preparation and properties. This fi nding stimulated

much activity in search of related materials and

has attracted increased attention to platinum as a

component of layered superconductors. This review

presents experimental and theoretical results devoted

to two main groups of superconducting materials with

platinum: Pt-based materials (where Pt forms individual

sub-lattices inside building blocks of corresponding

phases such as SrPtAs, SrPt2As2 and LaPt2B2C) and

Pt-containing materials, where Pt acts as a dopant.

Synthesis, basic properties and simulation of these

materials are covered.

1. Introduction Platinum and a rich series of Pt-based alloys and

compounds (as bulk, fi lms or nanostructured

species) are well known as critical materials for many

applications (besides jewellery and investment) – for

example they are excellent catalysts for chemical

processing, and have many uses in the automotive

industry (for example, in catalytic converters, spark

plugs and sensors), in electronics (for high-temperature

and non-corrosive wires and contacts), in petroleum

refi ning, and also in medicine, electrochemistry and

fuel cells. However, the participation of Pt in the

formation of superconducting materials is much

less well known (1–3). Superconductors fi nd use in

applications such as magnetic levitation (‘maglev’)

trains, magnetic resonance imaging (MRI) scanners

and particle accelerators and have further potential for

more effi cient electricity generation and distribution

as well as fast computing applications.

http://dx.doi.org/10.1595/147106713X663780 •Platinum Metals Rev., 2013, 57, (2)•


The face-centred cubic (fcc)-Pt metal remains non-

superconducting (1) even at the lowest accessible

temperatures of solid matter, T ~1.5 μK (4, 5). It is

believed that one of the obstacles to a possible

superconducting transition is the purity of the

metal, especially with regard to the concentration

of magnetic impurities (6). Strong electron-phonon

coupling, favourable for the formation of Cooper pairs

in fcc-Pt, may also be a factor. Enhanced electronic

susceptibility and the Sommerfeld coeffi cient (owing

to low-dispersive near-Fermi bands and high carrier

concentration) bring Pt close to magnetic instability

(Stoner factor ~4 (7)), when spin fl uctuations may

completely suppress superconductivity in this

metal (4). A very low-temperature superconducting

transition (at TC ~1.9 mK) was observed for compacted

high-purity Pt powder with average grain sizes of ~2

μm (6, 7); for Pt powders with nanosized grains (~100–

300 nm) TC increases to ~20 mK (8, 9). It is supposed that

the granular structure and the lattice strains related to

local inhomogeneity (which is incommensurate with

the Fermi surface nesting vectors (10)) are the key

factors for the occurrence of inter- and intragranular

superconductivity in granular Pt (8–10). In any case,

‘pure’ Pt as a superconductor seems unlikely.

However, a new set of Pt-based alloys and

compounds represent very attractive groups of modern

superconducting materials, and these have become

the subjects of much research interest, particularly

owing to clear evidence of unconventional pairing

mechanisms for these systems.

Traditional John Bardeen, Leon Cooper and Robert

Schrieffer (BCS)-like theories of superconductivity

hold that pairs of electrons within nonmagnetic

materials are coupled to phonons. In the case

of unconventional superconductors, various

mechanisms without phonons are suggested.

For example, the unusual properties of UPt3 (11)

including a heavy fermion state below T = 20 K,

dynamic antiferromagnetism (AFM) with onset at

magnetic transition temperature, TN = 6 K, and an

anisotropic superconducting state with three distinct

superconducting phases, provide strong evidence for

unconventional spin-triplet superconductivity. In turn,

CePt3Si is the fi rst heavy-fermion superconductor

without inversion symmetry, and its discovery (12)

has initiated widespread research activity in the fi eld

of so-called noncentrosymmetric superconductors

(13–15). Recently such superconductors lacking

a lattice inversion centre have been investigated

for the possibility of spin-triplet dominated pairing

symmetry. Related Pt-based noncentrosymmetric

superconductors are also known: BaPtSi3 (16), Li2Pt3B

(17) and LaPt3Si (18).

Another exciting material is platinum hydride

(PtH) (19–21), for which the superconducting

transition was predicted at TC ~12 K (19) – the

highest superconducting transition temperature

among known metal hydrides – at pressure P ~90 GPa.

Recent theoretical estimates confi rm that the critical

temperature of the two high-pressure phases of PtH

correlates with electron-phonon coupling (19).

Another group of low-TC (< 8.5 K) superconductors

include germanium-platinum compounds with the

skutterudite-like crystal structure MPt4Ge12 (where

M are alkaline earth metals (strontium or barium),

rare earth metals, thorium or uranium) (23–26).The

majority of the listed Pt-based materials (a) belong

to three-dimensional (3D)-like crystals; and (b) adopt

low-temperature superconductivity.

One of the most remarkable achievements in

physics and materials sciences was the discovery of

high-temperature superconductors with TC values

equal to or above the historical limit of TC ~23 K

for niobium-germanium (Nb3Ge). Starting with the

discovery of the superconducting transition at TC =

35 K in Ba-doped La2CuO4 in 1986 (27), several exciting

families of high-TC materials were subsequently found.

Among these are the discoveries of superconductivity

in layered materials: MgB2 (TC ~39 K) in 2000 (28)

and fl uorine-doped LaFeAsO (TC ~26 K) in 2008 (29).

These discoveries have inspired worldwide research

efforts and have been the subject of many reviews

(30–51). Most recently, phases with considerably

increased values of TC ~56 K were synthesised

(Gd1–xThxFeAsO (52), Sr1–xSmxFeAsF (53) and

Ca1–xNd1–xFeAsF (54)), and these form a new class of so-

called iron-based high-temperature superconductors.

The unconventional superconductivity of these

materials, including various types of pairing and the

coexistence of superconductivity with magnetism, has

been widely discussed.

Several groups in this class of Fe-based

superconductors are now known. The majority of them

are iron-pnictide (Pn) (or chalcogenide (Ch)) phases

(Fe-Pn or Fe-Ch, respectively). These materials can be

categorised into the following major groups. From

the chemical point of view, the simplest of them are

binaries: 11-like phases (such as FeSex (45, 55)); ternary

111-like (such as AFeAs, where A are alkali metals

(56)) and 122-like (such as BFe2Pn2, where B are alkali

earth metals (57), or AxFe2–yCh2 (58)) materials; and a



wide group of quaternary 1111-like superconductors

including pnictide oxides or pnictide fl uorides such as

RFeAsO (R are rare earth metals) and BFeAsF.

Recently, more complex materials such as

B3Sc2Fe2As2O5 (32225 phases) (59) and B4M2Fe2Pn2O6

(M are d block metals) (42226 (or 21113) phases)

were proposed (60, 61) as parent phases for new high-

TC superconductors (46). For some of these, relatively

high transition temperatures were established, for

example TC ~17 K for Sr4Sc2Fe2P2O6 (60) and TC

~37 K for Sr4V2Fe2P2O6 (61). This family was further

expanded when new pnictide oxides such as Can+2(Al,

Ti)nFe2As2Oy (n = 2, 3, 4) (62), Ca4Al2Fe2(P,As)2O6–y (63),

Sr4(Sc,Ti)3Fe2As2O8, Ba4Sc3Fe2As2O7.5, Ba3Sc2Fe2As2O5

(64), Ca4(Mg,Ti)3Fe2As2Oy (65), Sr4MgTiFe2Pn2O6

(66, 67), and Ba4Sc2Fe2As2O6 (68) were successfully

prepared and studied (69–77).

For all the listed iron-based superconducting

materials:

(a) The crystal structure includes two-dimensional

(2D)-like (Fe-Pn) (or Fe-Ch) blocks, which are

separated by A or B atomic sheets (for 111- and

122-like phases, respectively) or by (RO), (B3M2O5)

or (B2MO3) blocks for more complex 1111, 32225

or 21113 phases; the simplest 11-like binaries

consist of stacked (Fe-Ch) blocks;

(b) The electronic bands in the window around the

Fermi level are formed mainly by the states of

(Fe-Pn) (or Fe-Ch) blocks, which are responsible

for superconductivity, whereas the A and B atomic

sheets or oxide blocks, which are often termed

also as spacer layers, serve as insulating ‘charge

reservoirs’; and

(c) These materials have high chemical fl exibility to

a large variety of constituent elements together

with high structural fl exibility, and atomic

substitution inside the blocks (electron or hole

doping) is one of the main strategies for designing

new superconducting systems with desirable

properties (30–51).

The next promising step in expanding of this

family of high-temperature superconductors was

made in 2011, when a unique group of Pt-based

materials: 10-4-8 (Ca10(Pt4As8)(Fe2As2)5) and 10-3-8

((CaFe1–xPtxAs)10Pt3As8) phases was discovered

(78–80) and intensive studies of their properties were

initiated (81–85). For these materials superconductivity

has been detected up to TC ~35–38 K, which is probably

induced either by Pt doping of the blocks (FeAs) in

the 10-3-8 phase or by indirect electron doping in the

10-4-8 phase owing to additional Pt2+ in the platinum

arsenide blocks (78–80). Thus, the role of Pt in the

formation of superconducting materials becomes

very intriguing.

Pt as a component of layered superconducting

materials has been investigated for a long time,

and Pt has been found to play a triple role: (a) as a

dopant, (b) as a component of non-superconducting

blocks (spacer layers), and (c) as a component of

superconducting blocks. Thus, all superconductors

with Pt can be divided onto two groups: Pt-based

materials (where Pt forms individual sub-lattices

inside blocks) and Pt-containing materials, where Pt

acts as a dopant.

The following sections will focus on the above

mentioned materials to cover the basic issues of their

synthesis, main properties and simulation.

2. Pt-Based Superconducting MaterialsBesides the 10-3-8 and 10-4-8 phases, some other Pt-

based superconductors are known, such as SrPtAs

(86), SrPt2As2 (87) and RPt2B2C (where R are rare earth

metals or Th) (88–94), see Table I.

2.1 1221 Phases (Borocarbides)Historically, the systematic study of layered Pt-based

superconducting materials began with borocarbides

RPt2B2C (1221 phases) in the mid-1990s and was

continued in the new millennium (87–99). These

phases crystallise in the tetragonal LuNi2B2C-type

structure, which is an interstitial modifi cation of the

ThCr2Si2-type, and attract attention mainly because of

the coexistence of various types of magnetic ordering

and superconductivity. Since data about the properties

of these materials are discussed in detail in a set of

available reviews (100–104), here only the structural

and superconducting parameters for known Pt-

based superconductors are listed (Table I). All these

materials belong to the class of low TC superconductors.

2.2 SrPtAsIn 2011, the hexagonal phase SrPtAs was discovered

(86) as a new low-temperature superconductor with

TC ~4.2 K. Polycrystalline samples of SrPtAs were

prepared (86) by a solid-state reaction with PtAs2 as a

precursor mixed with Sr and Pt powders using several

steps of heating. SrPtAs adopts a hexagonal structure

(space group P63/mmc, #194) derived from the well-

known AlB2-type structure and can be schematically

described as a sequence of two honeycomb planar

sheets, where one plane is formed by Sr atoms, and the

other (PtAs) by hexagonal Pt3As3, see Figure 1. The



atomic coordinates are Sr: 2a (0;0;0), Pt: 2c (⅓ ;⅔ ;¼),

and As: 2d (⅔ ;⅓ ;¼), the lattice constants are a = 4.244 Å

and c = 8.989 Å (86, 105).

Some theoretical efforts have been undertaken

to predict the electronic and some other properties

of SrPtAs (106–108). It is thought that this material

should be characterised as a quasi-2D ionic metal

(106), which consists of metallic-like (PtAs) sheets

alternating with Sr atomic sheets coupled by ionic

interactions. The near-Fermi valence bands are

derived from the Pt 5d states with an admixture of the

As 4p states. The Fermi surface of SrPtAs is formed

by two quasi-2D (cylindrical-like) sheets parallel to

the kz direction (along the Г-A direction) and by two

sheets at the zone corners (around K-H). All the Fermi

surfaces are hole-like. A very small closed electronic-

like pocket was found around K, see Figure 2.

Table I

Pt-Based Layered Superconducting Materials: Structural Properties and Critical Temperatures, TC

Type Material Space

group

Lattice constants, Å TC, K Refs.

a b c

1221 YPt2B2C I4/mmm – – – 10–11 (88, 89)

LaPt2B2C I4/mmm 3.875 3.875 10.705 10.5–11 (88)

PrPt2B2C I4/mmm 3.837 3.837 10.761 6–6.5 (88, 89)

NdPt2B2C I4/mmm 3.826 3.826 10.732 2.5 (90, 91)

ThPt2B2C I4/mmm 3.83 3.83 10.853 6.7–7 (92–94)

111 SrPtAs P63/mmc 4.244 4.244 8.989 4.2 (86)

122 SrPt2As2 P4/nmm 4.46 4.51 9.81 5.2 (87)

10-4-8 (CaFe1–xPtxAs)10Pt4–yAs8; -phase

P4/n 8.716 8.716 10.462 ~11–31 (80)

(CaFe1–xPtxAs)10Pt4–yAs8; -phase, x ~0.13

P1 8.7282 8.7287 11.049 ~30 (80)

(CaFe1–xPtxAs)10Pt4–yAs8; x ~0.36

P1 8.719 8.727 11.161 32.7–38 (88)

10-3-8 (CaFe1–xPtxAs)10Pt3As8; x ~0.05

P1 8.776 8.781 10.689 ~11–35 (80)

(CaFe1–xPtxAs)10Pt3As8; x ~0.16

P1 8.795 8.789 21.008 13.7 (83)

Fig. 1. Crystal structures of: (a) AlB2 and (b) SrPtAs. The structure of SrPtAs can be described as an ordered variant of the AlB2-type structure, where the Al sites are occupied by Sr and the boron sites are occupied either by Pt or As atoms so that they alternate in the honeycomb layer as well as along the c-axis (86)

(a)

B

A1(b)

As

Pt

Sr



(a)

A

H

K

L

M

(b) 4

2

0

–2

–4

–6

Ener

gy, e

V

A L M K H A

EF

Fig. 2. (a) Fermi surface; and (b) Electronic bands of SrPtAs (106)

Taking into account the relativistic effects, this

small electronic-like pocket disappears (102), and

the Fermi surface of SrPtAs becomes fully hole-like.

This feature distinguishes SrPtAs from other layered

pnictogen-containing superconductors. It was also

pointed out that SrPtAs provides a prime example

of a superconductor with locally broken inversion

symmetry (107). The calculated anisotropy in Fermi

velocity, conductivity and plasma frequency related

to the layered structure were found to be enhanced

owing to spin-orbit coupling; further, it was predicted

that electron doping would be favourable for an

increase in TC (108). Finally, SrPtAs was found (106)

as a mechanically stable and soft material with high

compressibility lying on the border of brittle/ductile

behaviour, and the parameter limiting its mechanical

stability is the shear modulus G, Table II.

2.3 SrPt2As2

For the chemically similar phase SrPt2As2 (110), low-

TC superconductivity (~5.2 K) has also been found

(87), and this phase seems very attractive as the fi rst

superconductor from the wide family of related Pt-

containing 122-like materials: for example, ThPt2Si2,

YbPt2Si2, UPt2Si2, RPt2Si2 (R = La, Nd, Er, Dy, Ce),

ThPt2Ge2, YbPt2Si2, UPt2Ge2 and RPt2Ge2 (112).

Polycrystalline samples of SrPt2As2 were

synthesised using stoichiometric amounts of Sr,

PtAs2 and Pt powders by a solid-state reaction (87).

SrPt2As2 adopts a tetragonal CaBe2Ge2-type structure

(space group P4/nmm, #129) (87, 110, 111). The atomic

positions are Sr: 2c (¼, ¼, zSr); 2a (¾, ¼, 0); Pt2: 2c

(¼, ¼, zPt); As1: 2b (¾, ¼, ½); and As2: 2c (¼, ¼, zAs),

where zSr,Pt,As are the internal coordinates. The lattice

parameters are listed in Table I. This structure can be

Table II

Calculated Bulk Modulus (B, in GPa), Compressibility (, in GPa–1), Shear Modulus (G, in GPa), and

Pugh’s Indicator (G/B) for SrPtAs (106) and SrPt2As2 (113)

Phase/parameter SrPtAs SrPt2As2b SrPt2As2

c

BV,R,VRHa 79/10/44.5 101/99/100 71/71/71

0.023 0.010 0.014

GV,R,RVHa 30/15/22.5 27/25/26 29/5/17

G/B 0.51 0.26 0.24a B(G)V,R,RVH as calculated within Voigt (V)/Reuss (R)/Voigt-Reuss-Hill (VRH) approximations, see for example (109)

b For SrPt2As2 polymorphs of CaBe2Ge2-type

c For SrPt2As2 polymorphs of ThCr2Si2-type



schematically described as a sequence of Sr sheets

and [Pt2As2] and [As2Pt2] blocks consisting of {PtAs4}

and {AsPt4} tetrahedrons: …[Pt2As2]/Sr/[As2Pt2]/Sr/

[Pt2As2]/Sr/[As2Pt2]… as shown in Figure 3.

For SrPt2As2, superconductivity coexists with the

charge density wave (CDW) state (87) and this material

exhibits a CDW transition at about 470 K (110).

Theoretical probes (113, 114) predict that SrPt2As2

is essentially a multiple-band system, with the Fermi

level (EF) crossed by Pt 5d states with a rather strong

admixture of As 4p states, Figure 4. It was found (113)

that CaBe2Ge2-type SrPt2As2 is a unique system with an

‘intermediate’-type Fermi surface (Figure 3), which

consists of electronic pockets having a cylinder-like

(2D) topology (typical of 122 FeAs phases) together

with 3D-like electronic and hole pockets. The latest

are characteristic of ThCr2Si2-like iron-free low-TC

superconductors. The non-monotonic behaviour of

the density of states (DOS, see Figure 4) near the EF

suggests the possibility of signifi cant changes of TC

due to various (electron or hole) doping.

Analysis (113) revealed that other features of

CaBe2Ge2-like SrPt2As2 are as follows:

(a) Essential differences in contributions to the

near-Fermi region from the [Pt2As2] and [As2Pt2]

blocks when conduction is anisotropic and

occurs mainly in [Pt2As2] blocks;

(b) Formation of a 3D system of strong covalent Pt-As

bonds (inside and between [Pt2As2]/[As2Pt2]

blocks, see Figure 3), which is responsible

for enhanced stability of this polymorph – in

comparison with the competing ThCr2Si2-like

phase; and

(c) Essential charge anisotropy between adjacent

[Pt2As2] and [As2Pt2] blocks.

It has also been predicted that CaBe2Ge2-like

SrPt2As2 will be a mechanically stable and relatively

soft material with high compressibility, which will

behave in a ductile manner, Table II. However, the

ThCr2Si2-type SrPt2As2 polymorph, which contains

only [Pt2As2] blocks, is less stable and will be a ductile

material with high elastic anisotropy.

A family of higher-order polytypes has been

proposed (113), which can be formed as a result of

various stacking arrangements of the two main types

of building blocks ([Pt2As2] and [As2Pt2]) in different

combinations along the z axis. This may provide

an interesting platform for further theoretical and

experimental work in the search for new Pt-based

superconducting materials.

In 2012, a new family of related ternary platinum

phosphides APt3P (A = calcium (Ca), strontium (Sr)

or lanthanum (La)) was discovered (115). These

phases crystallise in a tetragonal structure, where

(a) (b)

AsPt

Sr

AsPt

PtAs

Sr

AsPt

ZR

XM

A

A

Z

P

X

N

As As

As

As

Sr Sr

Pt Pt

Pt

Pt

(c) (d)

Fig. 3. Left: Crystal structures of: (a) SrPt2As2 with CaBe2Ge2-type; and (b) ThCr2Si2-type structures (87) and the corresponding Fermi surfaces (113). Right: Charge density maps of SrPt2As2 polymorphs illustrating the formation of directional “inter-block” covalent bonds: (c) As-Pt bonds for CaBe2Ge2-type; and (d) As-As bonds for ThCr2Si2-type structures (113)



Den

sitie

s of

sta

tes,

eV

–1 f

orm

ula

unit–1 10

5

0

10

5

0–8 –6 –4 –2 0 2 4

Energy, eV

(a)

(b)

EFTotalPt1 5dPt2 5dAs1 4pAs2 4p

TotalPt 5dAs 4p

Fig. 4. Total and partial densities of states (DOSs) of SrPt2As2 polymorphs with structures of: (a) CaBe2Ge2-type; and (b) ThCr2Si2-type (113)

the anti-perovskite units Pt6P are placed between Sr

sheets. All three materials showed low-temperature

superconductivity. The highest TC ~8.4 K was found for

SrPt3P. Local-density approximation (LDA) calculations

(116) reveal the 3D-like multiple band structure of

APt3P phases. The increase of TC for SrPt3P with hole

doping (for example, by partial replacement of Sr with

potassium (K), rubidium (Rb) or caesium (Cs)) was

predicted.

2.4 Quaternary 10-4-8 and 10-3-8 Superconducting PhasesIn 2011, superconductivity with TC ~25 K was reported

for the tetragonal phase Ca10(Pt4As8)(Fe2As2)5 formed

in the quaternary Ca-Pt-Fe-As system (76). Very

soon, additional reports (78, 80) became available,

where the related Ca-Pt-Fe-As systems are examined

and enhanced superconductivity with transition

temperatures up to TC ~38 K, achieved by substitution

of Pt for Fe in the (Fe2As2) blocks, is reported.

One of the most intriguing features of these new Pt-

based materials (78–85) is the presence of (Fe2As2)

blocks, which are typical of the family of Fe-Pn

superconductors, together with oxygen-free blocks

[PtnAsm].

Based on Zintl’s chemical concept of ion electron

counting, it was proposed (79, 80) that [Pt4As8] and

[Fe2As2] blocks in the Ca10(Pt4As8)(Fe2As2)5 phase are

metallic-like (i.e. both blocks will give appreciable

contributions to the density of states at EF) leading

to enhanced inter-block coupling and thus to an

enhanced transition temperature of this system. It

has also been suggested that similar phases with

additional metallic-like blocks might provide an

interesting platform for the discovery of novel high-TC

superconducting materials.

Single crystals of Ca10(PtnAs8)(Fe2–xPtxAs2)5 were

grown (78) by heating a mixture of Ca, FeAs, Pt and

As powders. The mixture was placed in an alumina

crucible, sealed in an evacuated quartz tube, and

heated in one of two ways. Heating at 700ºC for 3 h

and then at 1000ºC for 72 h followed by slow cooling

to room temperature yielded an -phase with TC ~38 K,

whereas heating at 1100ºC and slow cooling to 1050ºC

for 40 h yielded a -phase with TC ~13 K (78).

The atomic structures of the -phase Ca10(Pt4As8)-

(Fe2–xPtxAs2)5 (termed also as 10-4-8 phase) and the

-phase Ca10(Pt3As8)(Fe2–xPtxAs2)5 (10-3-8 phase) are

depicted in Figure 5; the lattice parameters are listed

in Table I.These structures can be schematically described as

a sequence of 2D-like [Pt4As8]([Pt3As8]) and [Fe2As2]5

blocks separated by Ca sheets; in turn, platinum-

arsenide blocks [Pt4As8]([Pt3As8]) are formed by

corner-shared {PtAs4} squares, whereas iron-arsenide

blocks consist of {FeAs4} tetrahedrons. In both cases

[Pt4As8]([Pt3As8]) and [Fe2As2]5 blocks contain a set

of non-equivalent types of Fe, Pt and As atoms (78–85).

Further studies of superconducting gap anisotropy

(82), low energy electronic structure, and Fermi

surface topology (using angle resolved photoemission

spectroscopy, see Figure 5) (117), the critical magnetic

fi elds (118), and some transport properties (84, 119)

together with theoretical calculations of the electronic



band structure and parameters of interatomic bonds

(80, 81) reveal some interesting features of these

materials. In particular, Pt doping into FeAs blocks

was found to play a critical role for the occurrence of

superconductivity. This doping-dependent evolution

of the superconducting state is illustrated in Figure 6,

where the electronic phase diagram for Ca10(Pt3As8)-

(Fe2–xPtxAs2)5 is depicted. About 2 wt% Pt doping

produces superconductivity, and the superconducting

transition temperature reaches its maximum TC ~13.6 K

in the doping range 0.050 < x < 0.065. With further Pt

doping, TC slowly decreases.

The fi rst studies of electronic properties and

interatomic bonding (80, 81) reveal that for

Ca10(Pt4As8)(Fe2As2)5:

(a) The electronic bands in the window around the

Fermi level are formed mainly by the Fe 3d states

of [Fe2As2]5 blocks;

(b) The [Pt4As8] blocks will behave as semi-metals

with very low densities of states at the Fermi level;

(c) The near-Fermi bands adopt a ‘mixed’ character:

simultaneously with quasi-fl at bands, a series of

high-dispersive bands which intersect the Fermi

level was found; and

(d) The chemical bonding in Ca10(Pt4As8)(Fe2As2)5 is

complicated and includes an anisotropic mixture

of covalent, metallic and ionic interatomic and

inter-block interactions, see Figure 7.

Inside [Fe2As2]5 blocks covalent Fe-As and metallic-

like Fe-Fe bonds take place, whereas inside [Pt4As8]

blocks a system of covalent Pt-As and As-As bonds

emerges. Further, inside these blocks interatomic

ionic interactions occur owing to charge transfer

Fe As and Pt As. The inter-block charge transfer

occurs from the electropositive Ca ions to [Pt4As8]

and [Fe2As2]5 blocks. It is important that the charge

transfer Ca10 [Pt4As8] is much greater than the

transfer Ca10 [Fe2As2]5, i.e. in contrast to the

majority of known superconducting Fe-containing

materials (38–43, 51), the new phase Ca10(Pt4As8)-

(Fe2As2)5 includes two negatively charged blocks,

where the charge of the conducting [Fe2As2]5 blocks

is much smaller than for the Pt-As blocks. The

chemical modifi cation of PtnAs8 blocks may lead

(a) (b) (c)

Fe2As2

Ca

Pt4As8

Ca

Ca

CaFe2As2

Fe2As2

Fe2As2

Pt3As8

X0

Z0/

/Z0

M0kZ//kc//kc0

ky//kb0

kx//ka0

Fig. 5. Crystal structures of: (a) 10-4-8 phase (-phase Ca10(Pt4As8)(Fe2–xPtxAs2)5); (b) 10-3-8 phase (-phase Ca10(Pt3As8)(Fe2–xPtxAs2)5) (83); and (c) Experimentally-derived Fermi surface for the -phase (117)

Semiconducting

Superconducting

Metallic

0 0.02 0.04 0.06 0.08 0.10Platinum doping level, x

Tem

pera

ture

, K

100

10

Fig. 6. Electronic phase diagram for Ca10(Pt3As8)-(Fe2–xPtxAs2)5 (84) which illustrates the doping-dependent formation of semiconducting, metallic-like, and superconducting states for this material



to the discovery of similar materials with increased

TC (83).

3. Platinum-Doped Layered Superconducting MaterialsThe fi rst attempts to investigate Pt as a dopant

which can optimise the properties of layered

superconductors were undertaken as early as the

1990s when the high-temperature superconductor

cuprates were examined (120, 121). Next, the effects

induced by Pt doping of 1221 phases (borocarbides),

which exhibit a rich variety of phenomena associated

with superconductivity, magnetism, and their interplay,

were studied (122–131).

For non-magnetic superconductors such as YNi2B2C

and LuNi2B2C, the introduction of Pt atoms at the nickel

sites leads to modifi cations of their superconducting

properties. For series of single crystals of YNi2–xPtxB2C

(x = 0.02, 0.06, 0.1, 0.14 and 0.2), which were grown by

the travelling solvent fl oating zone method (125), with

an increase in the Pt content the critical temperature

decreases from TC ~15.9 K to TC ~13 K for x = 0.14,

Figure 8. The results were explained (125) assuming

the increase in inter-band scattering in the multi-band

superconductor YNi2B2C.

Pseudo-quaternary samples Y(Pd1–xPtx)2B2C were

prepared by mechanical alloying followed by a

thermal treatment (126). It was found that Pt stabilises

(a) (b) (c)

Fe 3dPt 5d

6

4

2

0

–2

–4

–6

Ener

gy, e

V

Pt-As

0.50

–0.5

Pt 5d

0 1

Densities of states, arbitrary units

Crystal orbital Hamilton population, arbitrary units

Bonding

Pt Pt

PtPtAs

As

As

AsAs

As

As

As6

4

2

0

–2

–4

–6En

ergy

, eV

Fig. 7. (a) Partial density of states; and (b) Crystal orbital Hamilton population (COHP) of the Pt-As bonds (80); and (c) Charge density map for Ca10(Pt4As8)(Fe2As2)5 phase, which illustrates the formation of directional covalent As-As bonds inside (Pt4As8) blocks (81)

0

–0.2

–0.4

–0.6

–0.8

–1.0

(a) (b)

AC

susc

eptib

ility

, ‘

12 13 14 15 16Temperature, K

10

8

6

4

T C a

nd T

N, K

0 0.05 0.10 0.15 0.20Platinum concentration, x

TC

TN

x = 0x = 0.02

x = 0.06

x = 0.1

x = 0.14

x = 0.2

Fig. 8. (a) Normalised real part of alternating current (AC) susceptibility as a function of temperature in YNi2–xPtxB2C (125); and (b) Superconducting transition temperature (TC) and magnetic transition temperature (TN) in Er(Ni1–xPtx)2B2C as functions of the Pt concentration, x (131)



the formation of the tetragonal superconducting

phase YPd2B2C (which adopts the highest TC ~23 K

among the borocarbides), when an almost single-

phase material with TC near 15 K for Y(Pd0.8Pt0.2)2B2C

was formed after annealing at 1273 K.

For magnetic superconductors such as ErNi2B2C,

the introduction of Pt atoms infl uences both TC and

TN (129–131). For example the measurements for

Er(Ni1–xPtx)2B2C (polycrystalline samples with

Pt content x = 0.0, 0.05, 0.10, 0.15 and 0.20 were

synthesised by standard arc melting under protective

argon atmosphere (131)) reveal that the variation of TC

as a function of x contains two intervals, see Figure 8.

At the fi rst step, a strong decrease in TC in the range 0 ≤

x < 0.10 occurs, whereas a much weaker drop of TC was

observed with a further increase of x (131). The value

of TN, by contrast, decreases almost monotonically.

Thus, the Pt impurities in superconducting 1221

borocarbides usually lead to reduction of TC. The

explanation of the observed effects requires further

studies.

A different effect accompanies the introduction

of Pt inside layered 122-like Fe-based pnictides

such as BFe2Pn2 (132–136). It is known that ‘pure’

BFe2Pn2 phases (parent materials for Fe-based

superconductors) are located on the border

of magnetic instability and commonly exhibit

temperature-dependent structural and magnetic

transitions with the formation of collinear AFM spin

ordering, whereas superconductivity emerges either

as a result of hole or electron doping into these

parent compounds (38–43, 47). Accordingly, this effect

was observed for some Pt-doped 122-like phases.

Polycrystalline samples of SrFe2–xPtxAs2 (0 ≤ x ≤ 0.4)

were prepared by a solid-state reaction method using

SrAs, FeAs and metallic powders of Fe and Pt as

reagents. The mixture was pressed into a Ta capsule,

sealed in an evacuated quartz tube, and heated at

1000ºC for 48 h. The measurements demonstrated

that as a result of Pt doping, the magnetic order of the

parent phase SrFe2As2 is suppressed, superconductivity

for SrFe2–xPtxAs2 emerges at approximately x = 0.15,

and TC reaches a maximum of 16 K at x = 0.2 (132).

A similar effect was detected for the related system

BaFe2–xPtxAs2 (133), where at the doping level of x ~0.1

the maximum transition temperature TC ~25 K was

achieved. This situation is well illustrated in Figure 9,

where the electronic phase diagram of BaFe2–xPtxAs2

for the doping range x = 0–0.25 is depicted. In a

simplifi ed way, these effects can be interpreted in

terms of the difference in the number of valence

electrons between the doped transition metal (Pt) and

iron, i.e. the chemical scaling of the electronic phase

diagram (137, 138).

However, some exceptions can exist here: for

the related system CaFe2–xPtxAs2 it was established

(134) that the substitution of Pt is ineffective in the

reduction of AFM ordering as well as for inducing of

superconductivity up to a solubility limit at x ~0.08.

This challenge calls for further studies.

4. ConclusionsThis overview has covered the relatively little-known

role of platinum in design and modifi cation of modern

superconducting materials. The main goal was to

highlight recent experimental and theoretical results

that may give an insight into the current status and

possible development of layered superconducting

materials with Pt.

To date, two types of such materials have been

discovered: Pt-based materials (where Pt forms

individual sub-lattices inside building blocks of

corresponding phases such as SrPtAs, SrPt2As2, LaPt2B2C

and (CaFe1–xPtxAs)10Pt3As8) and Pt-containing materials

(such as Y(Pd1–xPtx)2B2C or SrFe2–xPtxAs2), where Pt acts

as a dopant. The role of Pt can be radically different. For

example, the Pt impurity in superconducting borocarbides

usually leads to a reduction of TC; whereas the

introduction of Pt inside layered Fe-based pnictides such

as BFe2Pn2 leads to the occurrence of superconductivity

(with high transition temperatures to TC ~25 K) in these

non-superconducting parent materials. A very promising

Fig. 9. Phase diagram of BaFe2–xPtxAs2 for the doping level x = 0–0.25 (133). At x < 0.02 a magnetic state with AF spin fl uctuations exists. Superconductivity appears at x = ~0.02, and TC reaches its maximum value (25 K) at x = 0.1

Tem

pera

ture

, K

150

100

50

0 0.05 0.10 0.15 0.20 0.25Platinum concentration, x

Antiferro-magnetic

Superconducting



step in expanding the family of superconducting

materials with Pt was made in 2011, when the unique

quaternary phases: 10-4-8 (Ca10(Pt4As8)(Fe2As2)5) and

10-3-8 ((CaFe1–xPtxAs)10Pt3As8) with highest TC ~35–38

K were discovered.

The author hopes that this overview will be useful as

a compendium to guide further research into layered

superconducting materials with Pt, which seem

interesting and challenging systems for providing new

and promising superconductors.

AcknowledgementsFinancial support from the Russian Foundation for

Basic Research (RFBR) (Grant 12-03-00038-a) is

gratefully acknowledged.

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The AuthorAlexander L. Ivanovskii completed his PhD in 1979 at the Institute of Solid State Chemistry in Ekaterinburg, Russia, and accomplished his habilitation in Chemistry at the same institute in 1988. He was promoted to Professor in 1992 and since 1994 he has been head of the Laboratory of Quantum Chemistry and Spectroscopy at the Institute of Solid State Chemistry at the Ural Branch of the Russian Academy of Sciences. Professor Ivanovskii is the author or coauthor of more than 470 research articles and 12 monographs. His main research interests are focused on the theory of electronic structure, chemical bonds, and computational materials science of superconductors, superhard materials and inorganic nanostructures.



CAT4BIO Conference: Advances in Catalysis for Biomass ValorizationHighlights of platinum group metal catalysts development for conversion of biomass to energy, fuels and other useful materials


Reviewed by Eleni Heracleous

Laboratory of Environmental Fuels and Hydrocarbons, Chemical Process Engineering Research Institute, Centre for Research and Technology Hellas, 6th klm Charilaou – Thermi Road, PO Box 361, 57001 Thermi, Thessaloniki, Greece

Angeliki Lemonidou*

Laboratory of Petrochemical Technology, Department of Chemical Engineering, Aristotle Univerisity of Thessaloniki, 54124 Thessaloniki, Greece

*Email: [email protected]

Introduction The transformation of biomass into fuels and

chemicals is becoming increasingly popular as a

way to mitigate global warming and diversify energy

sources. Catalysis will serve as key technological driver

to achieve effi cient and practical biomass conversion

routes to useful products. As part of the satellite

conferences complementing the 15th International

Congress on Catalysis 2012 (held 1st–6th July 2012,

in Munich, Germany), the Greek Catalysis Society

organised CAT4BIO, an international conference

on “Advances in Catalysis for Biomass Valorization”,

that was successfully held in Thessaloniki, Greece,

on 8th–11th July 2012 (1). The conference was held

under the auspices of the Aristotle University of

Thessaloniki (AUTH) and the Centre for Research and

Technology Hellas (CERTH), with fi nancial support

from the Faculty of Engineering and the Department

of Chemical Engineering at AUTH and the School

of Engineering of the University of Patras. Industrial

sponsors included the companies Arkema (France),

BIOeCON (The Netherlands) and Hellenic Petroleum

(Greece).

The conference’s scientifi c programme covered

the most recent progress in fundamental and applied

catalysis research for the conversion of biomass. It

consisted of eight keynote lectures from internationally

renowned experts in the fi eld, 36 high quality oral

presentations and 95 posters from research groups

worldwide. The programme was organised in nine

sessions, structured around the following main topics:

(a) Conversion of cellulose/hemicellulose into

platform molecules;

(b) Conversion of oils extracted from seeds and algae;

(c) Conversion of biomass into fuels and chemicals

via thermochemical processes;

(d) Catalytic routes for lignin valorisation; and

(e) Upgrading of biomass-derived products to high

added value fuels and chemicals.



Overall, there was excellent attendance with around

135 participants from both industry and academia from

28 countries worldwide. The conference succeeded in

serving as a platform for the presentation of the most

recent progress in fundamental and applied catalysis

research for the conversion of biomass. Presenters

shared their most up to date results on catalyst design,

synthesis and characterisation, surface and catalytic

reaction mechanisms and catalytic reaction processes

in the area of biomass valorisation. The conference

also provided ground for fruitful discussions among

catalysis experts from industry and academia. Selected

oral and poster contributions will be published as

full papers in a special issue of Applied Catalysis B:

Environmental (2).

This review focuses on the progress presented at the

conference on platinum group metal (pgm) catalysts

for the conversion of biomass to fuels and chemicals.

The main bulk of the pgm work reported at CAT4BIO

involved platinum catalysts, followed by papers on

ruthenium, palladium and rhodium. The highlights of

the pgm work presented in this review are categorised

based on the type of reaction employed for the

conversion of biomass and biomass-derived products

to high added value fuels and chemicals.

Hydrolysis of Cellulose/Hemicellulose to Platform ChemicalsThe catalytic conversion of cellulose to platform

chemicals has gained increasing research attention in

the past decade. Noble metal catalysts can be used to

achieve the one-pot synthesis of sorbitol from cellulose,

however commercial application is hindered by the

cost of the catalyst. The high stability of cellulose

presents another problem, as the reaction requires

harsh process conditions which degrade the fi nal

products and reduce selectivity. In a paper presented

by Jorge Beltramini and coworkers (University of

Queensland and Monash University, Australia), it

was shown that small amounts of Pt promote nickel

catalysts and signifi cantly improve their catalytic

activity. This synergistic effect was attributed to Pt and

Ni particles in close vicinity. Figure 1 shows sorbitol

and mannitol yields, as well as cellulose conversion,

from the aqueous phase hydrolysis and hydrogenation

of cellulose using supported alumina and alumina

nanofi bre (‘Alnf’) catalysts.

Hirokazu Kobayashi and colleagues (Hokkaido

University, Japan) showed that cellulose can also

be hydrolysed effectively to glucose by carbon-

supported Ru catalysts. 2 wt% Ru supported on

ordered mesoporous CMK-3 carbon gave a yield of

24% glucose and 16% cello-oligosaccharides at 503 K.

The conversion of cellulose was 56%, and thereby

the selectivity for glucose was 43%. The conversion

of cellulose was slightly improved by increasing

the content of Ru. This showed that the Ru species

hydrolyse both cellulose and oligosaccharides, and

show especially high activity for the latter substrate.

Results from X-ray absorption fi ne structure (XAFS)

Keynote LecturesProfessor Enrique Iglesia (University of California at Berkeley, USA), François Gault Lecture: ‘Monofunctional and Bifunctional C–C and C–O Bond Formation Pathways from Oxygenates’

Professor Johannes Lercher (Technical University of Munich, Germany), ‘From Biomass to Kerosene –

Tailored Fuels via Selective Catalysis’

Professor Daniel Resasco (University of Oklahoma, USA), ‘Deoxygenation of Phenolics, Acids and

Furfurals Derived from Biomass’

Professor Atsushi Fukuoka (Hokkaido University, Japan), ‘Conversion of Cellulose into Sugar

Compounds by Carbon-Based Catalysts’

Professor George Huber (University of Massachusetts, USA), ‘Aqueous Phase Hydrodeoxygenation of

Carbohydrates’

Jean Luc Dubois (ARKEMA, France), ‘Added Value of Homogeneous, Heterogeneous and Enzymatic

Catalysts in Biorefi neries’

Paul O’Connor (BIOeCON, The Netherlands), ‘Catalytic Pathways towards Sustainable Biofuels’

Claire Courson (University of Strasbourg, France), ‘Strategy to Improve Catalytic Effi ciency for Both

Thermal Conversion of Biomass, Tar Reduction and H2S Absorption in a Fluidized Bed’



analysis for the Ru catalyst were also presented.

Characterisation showed that the Ru species on CMK-3

is not metal but RuO2·2H2O regardless of the hydrogen

reduction in its preparation. Accordingly, one possible

origin for the catalytic activity is that the Ru species

works as Brønsted acid by the heterolysis of water

molecules on Ru.

Hydrogen Production via Reforming of Biomass-Derived ProductsA good number of contributions dealt with the use

of pgms, mainly Pt, for the reforming of alcohols

and other oxygenates from biomass to hydrogen.

Leon Lefferts (University of Twente, The Netherlands)

presented interesting results on the aqueous phase

reforming of ethylene glycol in supercritical water over

Pt-based catalysts. Ethylene glycol was investigated as

a representative model compound for the aqueous

phase of bio-oil, derived from biomass pyrolysis. Pt/Al2O3

and Pt-Ni/Al2O3 catalysts, although active in the

reaction, were shown to deactivate rapidly with time

on stream. Acetic acid, an intermediate of the reaction,

was shown to be responsible for the deactivation of

Pt and Pt-Ni catalysts. The presenter explained that

acetic acid behaves as a strong acid in sub- and

supercritical water resulting in hydroxylation of the

Al2O3 surface. Redeposition of the dissolved Al2O3 on

the catalyst leads to blocking of catalytic Pt sites and

hence deactivation of the catalyst, as observed with

transmission electron microscopy (TEM) (Figure 2).

Taking their work one step further, the authors

reported the development of stable Pt catalysts for

ethylene glycol supercritical aqueous phase reforming

supported on carbon nanotubes (CNTs). CNTs were

found to be stable in hot compressed water. Moreover,

the Pt/CNT catalysts exhibited stable activity for the

reforming of both ethylene glycol and acetic acid,

confi rming that deactivation of Pt/Al2O3 is caused by

the support and demonstrating the great importance

of the type of support for reactions under supercritical

conditions. The aqueous phase reforming of ethylene

glycol and other polyols (glycerol and sorbitol) over

Pt supported on hollow-type ordered mesoporous

carbon (OMC) with three-dimensional (3D) pore

structure was also reported in a poster contribution

by Chul-Ung Kim and colleagues (Korean Research

Institute of Chemical Technology, Korea). Better

catalytic performance, including carbon conversion,

hydrogen selectivity, yield and production rate was

observed over these materials, implying that 3D

interconnected mesopore systems allow faster pore

diffusion of reactive molecules.

The steam reforming of bioethanol over Pt catalysts

was discussed in two oral presentations at the

Fig. 1. Sorbitol and mannitol yield and cellulose conversion from the aqueous phase hydrolysis and hydrogenation of cellulose using supported platinum and nickel on alumina and alumina nanofi bre (Alnf) catalysts (Courtesy of Jorge Beltramini, University of Queensland, Australia)

Catalysts

55

50

45

40

35

30

25

20

15

35

30

25

20

15

10

5

0

Conversion, %

Yiel

d, %

Ni/Alnf

Ni/Al 2O

3

Pt/Alnf

Pt/Al 2O

3

Ni-Pt/A

lnf

Ni-Pt/A

l 2O3

MannitolSorbitolCellulose



conference. An especially interesting contribution,

reporting mechanistic aspects of the reaction over

Pt, came from the group of Professor Xenophon

Verykios (University of Patras, Greece). Paraskevi

Panagiotopoulou (University of Patras, Greece)

fi rst presented a very systematic work on ethanol

reforming over catalysts with different pgms (Pt, Pd, Rh

and Ru) and different supports (zirconia, Al2O3 and

ceria). Catalytic performance was found to depend

strongly on the nature of the dispersed metallic

phase employed, with Pt and Pd exhibiting good

activity and selectivity towards hydrogen. However,

the presenter showed that specifi c activity is defi ned

primarily by metal crystallites and secondarily by

metal/support interface. The normalised reaction rates

were found to increase with decreasing perimeter of

the metal/support interface and with increasing Pt

crystallite size, implying that active sites are terrace

sites and that ethanol adsorbs fl at on the Pt surface.

In situ diffuse refl ectance infrared Fourier transform

spectroscopy (DRIFTS) experiments also showed

that the oxidation state of Pt seems to affect catalytic

activity, which decreases with increasing population

of adsorbed carbon monoxide (CO) species on

partially oxidised (Pt+) sites. Moreover, the combined

results of temperature programmed surface reaction

(TPSR) and in situ DRIFTS experiments provided

evidence that the key step for ethanol reforming at low

temperatures is the ethanol dehydrogenation reaction,

producing surface ethoxy species and subsequently

acetaldehyde, which is further decomposed toward

methane, hydrogen and carbon oxides.

Similar conclusions were also reported in the

presentation of Filomena Castaldo et al. (University of

Salerno, Italy) who investigated the ethanol reforming

reaction over a 3 wt% Pt/10 wt% Ni/CeO2 catalyst.

Investigation of the reaction pathway by kinetic

experiments showed that ethanol steam reforming

is probably not the reaction that actually occurs at

370ºC. Instead, the involved reactions are most likely

to be the following: ethanol dehydrogenation; ethanol

and acetaldehyde decomposition and reforming;

water gas shift reaction; and methanation. The same

seems to apply for feedstocks other than ethanol,

based on the work that was presented by Ricardo

Reis Soares (Universidade Federal de Uberlândia,

Brazil). This contribution reported results on glycerol

reforming over Pt/C catalysts and also showed that

dehydrogenation is the key limiting step of the reaction.

Moreover, the reaction is sensitive to the structure of

the Pt/C catalysts, with the activity decreasing and the

selectivity shifting towards acetol and glycolaldehyde

as particles decrease in size. In other words, C–O

cleavage seems to occur preferentially on smaller

particles.

In a poster contribution by Weijie Cai and Pilar

Ramírez de la Piscina (University of Barcelona,

Spain) and Narcís Homs (University of Barcelona

and Catalonia Institute for Energy Research, Spain),

the importance of pgms for the effective oxidative

reforming of bio-butanol was reported. Doping

of cobalt/zinc oxide catalysts with Rh, Ru and Pd

signifi cantly improved the catalytic performance and

stability of the materials, with CoRh/ZnO exhibiting the

Al2O3 support

2.5×

0.71 nm

Pt particle covered by migrated Al2O3

2 nm

0.71 nm

2.5×

Fig. 2. TEM image of a deactivated platinum catalyst for the aqueous phase reforming of ethylene glycol in supercritical water (Reproduced from (3), Copyright 2012, with permission from Elsevier)



Table I

Comparison of Palmitic Acid Conversion on Carbon- or Zirconia-Supported Metal Catalystsa

Catalyst Conversion, % Selectivity, %b Initial rate,mmol g–1 h–1

C15 C16 A B C

Raney Nic 100 71 3.7 16 4.6 4.6 2.0

5% Pt/C 31 98 1.6 0.2 – – 0.4

5% Pd/C 20 98 1.9 0.3 – – 0.3

5% Ni/ZrO2 100 90 0.8 9.0 – – 1.3

5% Pt/ZrO2 99 61 6.5 0.5 22 7.3 1.0

5% Pd/ZrO2 98 98 0.7 1.0 – 0.1 1.2

a Reaction conditions: 1 g palmitic acid, 100 ml dodecane, 0.5 g catalyst, 260ºC, 12 bar H2 with a fl ow rate of 20 ml min–1, 6 hb A: Lighter alkanes, B: 1-Hexadecanol, C: Palmityl palmitatec 0.25 g catalyst(Reproduced from (4), Copyright 2013, with permission from Wiley-VCH Verlag GmbH & Co KGaA)

best catalytic performance in bio-butanol oxidative

reforming.

Hydrodeoxygenation of Biomass and Biomass-Derived Products to Fuels and Chemicals Currently, there is considerable interest in investigating

the hydrodeoxygenation process, due to the high

oxygen content of the feedstocks used for the

production of renewable fuels. One of the main

advantages of the hydrodeoxygenation route relative

to other methods for making biomass-derived fuels

is that the corresponding renewable fuel product is

a high quality, oxygen free, hydrocarbon fuel which

can be readily blended with conventional petroleum-

based refi nery fuel blendstocks and components.

Johannes Lercher (Technical University of

Munich, Germany) reported exciting aspects of the

deoxygenation of components from both proteinaceous

biomass (grown in an aqueous environment) and

lignocellulose (grown terrestrially) during his keynote

lecture. Professor Lercher showed how detailed

knowledge of the elementary reaction steps and of

the surface chemistry of the catalyst components in

water allow suitable stable catalysts to be designed for

the aqueous phase hydrodeoxygenation of biomass

and biomass-derived components to alkanes. Results

relevant to pgms were shown on the kinetics of the

catalytic conversion of palmitic acid and intermediate

products, 1-hexadecanol and palmityl palmitate.

The impacts of the catalytically active metal (Pt, Pd

or Ni) and the support (C, ZrO2, Al2O3, silica, or the

zeolites HBEA or HZSM-5), as well as the role of H2,

were explored in order to elucidate the reaction

pathway. The speaker shared results on the conversion

of palmitic acid at 260ºC in the presence of H2 for

three monofunctional metal catalysts: Pt/C, Pd/C and

Raney Ni (Table I). High selectivity to n-pentadecane

was obtained on all three metals (70% on Ni; 98%

on Pt and Pd), but relatively low conversions were

attained on Pt and Pd at 31% and 20%, respectively.

A high selectivity to lighter hydrocarbons (16%)

through C–C bond hydrogenolysis together with a low

selectivity to palmityl palmitate (4.6%) was observed

over the Raney Ni catalyst. In a H2 atmosphere, the

direct decarboxylation or decarbonylation routes



proceeded in parallel to the hydrogenation pathway.

Direct decarboxylation and/or decarbonylation of fatty

acids were the major pathways on carbon supported

Pt or Pd, much faster than the hydrogenation of

the fatty acid. However, the hydrogenation route

took precedence over decarbonylation on the

pure metallic Ni, as the decarbonylation on Ni was

much slower than on Pt or Pd. When the support

was changed from carbon to ZrO2, the conversion

increased from 20–30% to 100% for supported 5 wt% Pt

and Pd catalysts under identical conditions, indicating

that the hydrogenation of fatty acids was promoted

by ZrO2. High selectivity for n-pentadecane (98%) was

observed on Pd/ZrO2, while Pt/ZrO2 led to a relatively

low selectivity towards C15 alkanes (61%) due to the

high concentrations of 1-hexadecanol (22%). Ni/ZrO2

also led to 90% selectivity towards n-pentadecane at

100% conversion. These results imply that by using

ZrO2 as support, the three metals (Pt, Pd and Ni)

varied the primary route from direct decarboxylation/

decarbonylation to hydrogenation-decarbonylation,

as large concentrations of alcohol intermediates were

observed during the reactions. Thus, support aided

hydrogenation became the primary route for reaction

on these ZrO2-based catalysts in H2. The three metals,

however, also led to different hydrogenolysis activities;

for example, Pt/ZrO2 or Pd/ZrO2 produced less than 1%

lighter alkanes, while Ni/ZrO2 led to 9%, in line with the

marked hydrogenolysis activity of Ni.

George Huber (University of Massachusetts,

USA) gave a comprehensive keynote lecture on the

aqueous phase hydrodeoxygenation of carbohydrates

to produce a wide range of products including C1–

C6 alkanes, C1–C6 primary and secondary alcohols,

cyclic ether and polyols. The lecture focused on the

hydrodeoxygenation of sorbitol, xylose and glucose,

as well as pyrolysis oils, and discussed several

aspects of the hydrodeoxygenation process, such

as catalytic challenges, chemistry, kinetic modelling

and reaction engineering. The reaction takes place

over Pt bifunctional catalysts that involve both metal

and acid sites. The presenter showed that three

classes of reactions occur during the aqueous phase

hydrodeoxygenation of carbohydrates: (a) C–C bond

cleavage on metal sites; (b) C–O cleavage reaction

on acid sites; and (c) hydrogenation on metal

sites. Figure 3 shows the rich reaction chemistry

involved in aqueous phase hydrodeoxygenation of

biomass derived oxygenates that according to the

speaker can be further tuned by adjusting the relative

reaction pathways through further catalyst design

and optimisation of reaction conditions. In terms of

catalyst design, Professor Huber showed that the Pt

metal sites and the acid sites can be atomically mixed

(as in the case of a Pt-ReOx/C catalyst) or atomically

separate (as in the case of a platinum/zirconium

phosphate catalyst). These differences in the catalyst

properties result in the formation of different products.

The product selectivity can be further adjusted by

tuning the metal to acid site ratio. The type of acid sites

is also important in this reaction to avoid undesired

coking reactions.

Another excellent keynote lecture was delivered by

Daniel Resasco (University of Oklahoma, USA) who

focused on the deoxygenation of phenolics, acids and

furfurals derived from biomass to monofunctional

compounds or hydrocarbons. Of interest to the progress

of pgms in the area of biomass valorisation were the

developed ruthenium/titania/carbon catalyst for the

liquid phase conversion of acetic acid to acetone and

the palladium-iron catalysts for the hydrogenation of

furfural. The novel Ru/TiO2/C catalyst proved to be very

effective at temperatures much lower than typically

needed for the reaction using existing catalysts. After

detailed characterisation of the material, Professor

Resasco proposed that the origins of this high activity

are the oxygen vacancies and the Ti3+ sites which

are promoted by the presence of Ru. Moreover, the

hydrophobicity of the carbon support is believed to

decelerate the inhibiting effect that water typically

has on catalysts with hydrophilic surfaces. Concerning

furfural conversion, the presenter showed that whereas

Pd is active for the decarbonylation of furfural

to furan and methylfuran, by alloying Fe with Pd

a dramatic change in selectivity occurs. It seems

that hydrogenolysis of the C–O bond is favoured on

Pd-Fe alloys, whereas on Pd the preferred reaction

is C–C bond breakage. Selectivity to methylfuran

was found to be a strong function of the degree

of Pd-Fe alloying. The extent of Pd-Fe interaction

also strongly depended on the type of support

(SiO2 > -Al2O3 > -Al2O3).

The pgm catalysts were also reported to be active

for the hydrodeoxygenation of fatty acids to renewable

diesel fuel. In an oral contribution from Bartosz

Rozmysłowicz (Åbo Akademi University, Finland),

Pd/C was shown to be an effective catalyst for the

deoxygenation of algae oil, tall oil fatty acids and

macauba oil, which were chosen as representative

renewable oils of different origins (algae, wood and

fruits). The presented work also included a set of kinetic

experiments which revealed the reaction pathway over



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Pd/C. The results showed that the catalyst deactivates

in a low hydrogen atmosphere due to unsaturation

of the feedstock. Moreover, deactivation is related to

feedstock purity and its production technology.

Worth mentioning is an interesting poster

contribution by the group of Regina Palkovits (RWTH

Aachen University, Germany) which demonstrated

the feasibility of using a heterogeneous Ru catalyst to

convert levulinic acid (LA), a versatile intermediate

that can be obtained directly from cellulose, to

-valerolactone (-VL), a compound that can be

utilised directly as a fuel additive. The contribution

investigated the effect of different supports (carbon,

TiO2, SiO2 and Al2O3) on 5 wt% Ru. Catalyst screening

demonstrated that variation of the catalyst support can

have a profound infl uence on the reaction outcome.

The Ru/C catalyst exhibited the highest -VL yield

(89.1%) when reacted with LA at 130ºC in an ethanol/

water solvent mixture.

Hydrogenolysis of Glycerol to ChemicalsGlycerol, a byproduct of biodiesel production, can be

converted by hydrogenolysis to different high value

added chemicals, such as 1,2-propanediol (1,2-PDO)

and 1,3-propanediol (1,3-PDO), which are promising

targets because of the high production cost using

conventional processes and the reasonably large

production scale. The production of propanediols

from glycerol, however, normally requires the use

of organic solvents and high hydrogen pressures.

Two contributions presented novel results on the

hydrogenolysis of glycerol to 1,2-PDO and 1,3-PDO

over Pd- and Pt-containing catalysts without the need

for externally added hydrogen. Gustavo Fuentes

(Universidad A. Metropolitana Iztapalapa, Mexico)

showed that it is possible to obtain 1,3-PDO and

1-hydroxyacetone with signifi cant selectivity (30%

and 46%, respectively at 220ºC) without the addition

of external hydrogen and without the production of

appreciable amounts of ethylene glycol, the main

degradation product in basic medium, over a copper-

palladium/titania-5% sodium catalyst. It is important

to note that the highest selectivity reported so far

for 1,3-PDO using hydrogen pressure is 34%, a value

comparable to the authors’ results.

Another approach to alleviate the need for an

external hydrogen supply is the in situ formation and

consecutive consumption of H2, either by using a part

of the glycerol via a reforming reaction or by adding

a hydrogen donor molecule via dehydrogenation.

Efterpi Vasiliadou and Angeliki Lemonidou (Aristotle

University of Thessaloniki, Greece) presented a novel

one-pot catalytic route for effi cient 1,2-PDO production

using a crude glycerol stream as a feedstock under

inert conditions in the presence of Pt-based catalysts

(Pt/SiO2 and Pt/Al2O3). A European patent application

has been fi led (5). The H2 needed for glycerol

conversion was formed via a methanol reforming-

glycerol hydrogenolysis cycle taking advantage of

the unreacted methanol after biodiesel production

through transesterifi cation. The use of a Pt/SiO2

catalyst results in satisfactory 1,2-PDO yields (~22%) at

250ºC, 3.5 MPa nitrogen and 4 h reaction time.

Concluding RemarksThe conversion of biomass and biomass-derived

compounds to platform molecules and high added

value fuels and chemicals is a dynamic area of

research, which holds the attention of numerous

research groups worldwide. It is clear that catalysis

plays a key role in achieving effi cient and practical

biomass conversion routes to useful products. The

CAT4BIO conference on “Advances in Catalysis

for Biomass Valorization” was a successful event,

where groups from all over the world presented the

most recent progress in fundamental and applied

catalysis research for the conversion of biomass.

As demonstrated in the conference, pgm constitute

essential components of catalysis research for

biomass conversion reactions. Either as main active

components or as promoters, pgms fi nd use in a wide

range of chemical reactions. Their impact will render

them an essential component of future catalytic

processes for biomass valorisation.

References1 CAT4BIO: International conference on “Advances in

Catalysis for Biomass Valorization”, Thessaloniki, Greece, 8th–11th July, 2012: http://www.cat4bio2012.gr/ (Accessed on 31st January 2013)

2 Appl. Catal. B: Environ., Special Issue: CAT4BIO, to be published

3 D. J. M. de Vlieger, B. L. Mojet, L. Lefferts and K. Seshan, J. Catal., 2012, 292, 239

4 B. Peng, C. Zhao, S. Kasakov, S. Fortaita, J. A. Lercher, Chem. Eur. J., 2013, 19, (15), 4732

5 E. Vasiliadou and A. Lemonidou, Aristotle University of Thessaloniki, Greece, European Appl. 11179515.9; August 2011



Angeliki Lemonidou is Professor of Chemical Engineering at Aristotle University of Thessaloniki, Greece, and Head of the Petrochemical Technology Laboratory. She holds a Bachelor’s degree in Chemistry and a PhD in Chemical Engineering from Aristotle University. Her research interests are in the area of catalysis and catalytic reaction engineering focusing on processes related to the valorisation of hydrocarbons and oxygenated compounds. Her expertise involves kinetic and mechanistic measurements of well-designed catalytic materials and their structural and morphological characterisation. She has extensively studied the performance of rhodium- and platinum-based catalysts in reforming and hydrogenolysis of biomass intermediates.

Eleni Heracleous is currently a Research Scientist at the Chemical Processes & Energy Resources Institute (CPERI) in the Centre for Research and Technology Hellas (CERTH) in Thessaloniki, Greece. She obtained her PhD in Chemical Engineering from Aristotle University of Thessaloniki in 2005, under the supervision of Professor Lemonidou. After her PhD she worked as a post-doc for two years in Shell Global Solutions in Hamburg, Germany. Since 2008, she works in CPERI and is involved in the development of tailor-made catalysts for the valorisation of hydrocarbons (mainly selective oxidation reactions) and the conversion of biomass to high added value ‘green’ chemicals and fuels, with a special focus on syngas conversion processes.

The Reviewers



Johnson, Matthey and the Chemical SocietyTwo hundred years of precious metals expertise


By William P. Griffi th

Department of Chemistry, Imperial College, London SW7 2AZ, UK

Email: w.griffi [email protected]

The founders of Johnson Matthey – Percival Johnson and

George Matthey – played important roles in the foundation

and running of the Chemical Society, which was founded in

1841. This tradition continues today with the Royal Society

of Chemistry and Johnson Matthey Plc.

The nineteenth century brought a ferment of discovery

and research to all branches of chemistry; for example

some twenty-six elements were discovered between

1800 and 1850, ten of them by British chemists,

including rhodium, palladium, osmium and iridium.

In 1841 the Chemical Society – the oldest national

chemical society in the world still in existence – was

established. Both Percival Johnson (Figure 1(a))

and George Matthey (Figure 1(b)) were prominent

members, Johnson being one of its founders.

The Origins of the Chemical SocietyAlthough there had been an earlier London Chemical

Society in 1824 it lasted for only a year (1). The Chemical

Society of London (‘of London’ was dropped in 1848)

was founded at a meeting held on 30th March 1841

at the Society of Arts in John Street (now John Adam

Street), London, UK; Robert Warington (1807–1867), an

analytical chemist later to become resident Director

of the Society of Apothecaries (2), was instrumental in

setting it up and his son, also Robert Warington, later

wrote an account of its history for its 1891 Jubilee (3).

There were 77 founder members, of whom Percival

Johnson was one: others included William Cock

(Figure 2) (later to join Johnson in his new fi rm –

see below), Thomas Graham (Professor of Chemistry

at University College and the Society’s fi rst President),

Lyon Playfair, John Daniell and Warren de la Rue (4).

Michael Faraday joined in the following year (5).

The aim of the new Society was “The promotion of

Chemistry and those branches of Science immediately

connected with it…” The annual subscription was to be

£2 or £1 for those living twenty or more miles outside

London. It gained a Charter of Incorporation in 1848



and occupied a series of premises before its Jubilee

in 1891. The original accommodation at the Society

of Arts in John Street became too cramped for the

successful enterprise; having failed to rent rooms at

the newly instituted Royal College of Chemistry at

Hanover Square (3) it moved in 1849 to No. 142 Strand.

In 1851 it moved to share premises with the Polytechnic

Institution at 5 Cavendish Square and then in 1857

relocated to Old Burlington House (3, 6). The latter had

been built in 1664–1667 for the Earl of Burlington, a

brother of Robert Boyle; Henry Cavendish lived there

in his early years (7). The accommodation was shared,

rather uneasily, with the Royal and Linnaean Societies

and comprised two back rooms on the east side of

the ground fl oor. In 1873 the Society moved to better

premises in ‘New’ Burlington House, an extension

built (1868–1873) in the Eastern part of the courtyard

by Richard Banks and Charles Barry (7). Here it has

remained, albeit with various room changes (7–9).

The Foundation of Johnson Matthey The involvement of the Johnson family in the platinum

metals industry dates back to John Johnson (1765–1831),

whose father (also John Johnson) had been an assayer

of ores and metals at No. 7 Maiden Lane, London, in

1777 (10–12). On his father’s death in 1786 his son

John became the only commercial assayer in London

and was involved in the rapidly developing platinum

trade (11, 12). He supplied William Hyde Wollaston

(1766–1826) with large quantities of platinum ore

from which Wollaston was to establish an efficient

process for isolation of pure platinum metal (11);

Wollaston also discovered and isolated rhodium

and palladium (13).

(a) (b)

Fig. 1. (a) Portrait of Percival Johnson (1792–1866); (b) Portrait of George Matthey (1825–1913)

Fig. 2. Portrait of William Cock (1813–1892)



In 1807 John Johnson’s son Percival Norton

Johnson (1792–1866) (11, 12, 14) was apprenticed to

the fi rm – he already had good scientifi c credentials,

having published a paper on ‘Experiments which

prove Platina, when combined with Gold and Silver,

to be soluble in Nitric Acid’ (15) (reproduced in

(16)). This showed that small quantities of platinum

mixed with gold and silver in nitric acid facilitated

a separation of pure gold from the solution. He

became a partner in 1817, the year often regarded

as that in which the fi rm, later to become Johnson

Matthey, was established (11, 17).

By happy chance, 1817 was also the year in which Sir

Humphry Davy showed that a platinum wire catalysed

the combination of hydrogen with oxygen in the air

and became white-hot in the process (18) and he

observed a similar effect when a coil of platinum (or

palladium) was placed within his wire gauze safety

lamp (19). These were really the fi rst observations of

heterogeneous oxidation catalysis (20, 21). In 1822

the business moved to 79 Hatton Garden and in 1826

Percival Johnson employed an assayer, George Stokes,

taking him into partnership in 1832. The fi rm was now

called Johnson and Stokes. On the death of Stokes in

1835 another assayer, William John Cock (1813–1892)

(11, 22), the son of Johnson’s brother-in-law Thomas

Cock (also an expert in platinum metallurgy),

joined Johnson in 1837 and the fi rm was now called

Johnson and Cock (22). Like Johnson, William Cock

was a founding member of the Chemical Society in

1841 and had devised a process for making platinum

more malleable. He wrote a paper in the fi rst volume

of the Memoirs of the Chemical Society of London,

the Society’s fi rst journal, titled ‘On Palladium – Its

Extraction, Alloys, &c.’ (23), a remarkable summary of

the preparation and major properties of palladium.

The fi rm of Johnson and Cock, amongst much other

business, provided platinum for a commemorative

medal for Queen Victoria’s coronation (Figure 3)

and 100 ounces of the metal for the new Imperial

pound weight standards in 1844. Cock resigned in

1845 through ill-health, though he continued to help

Johnson until much later.

George Matthey (1825–1913) (11, 24, 25) was taken

on as an apprentice by Johnson and Cock in 1838 at

the age of thirteen and quickly became interested in

platinum refi ning, William Cock becoming his mentor.

Matthey was an excellent chemist, having spent some

time at the Royal College of Chemistry in the late 1840s

with August Wilhelm von Hofmann (26). His younger

brother Edward later studied chemistry and metallurgy

at the sister institution the Royal School of Mines and

later became a partner in the company (11). George

had a shrewd business mind and he persuaded

a rather reluctant Johnson to show samples of

platinum, palladium, rhodium and iridium at the Great

Exhibition of 1851: these exhibits were awarded a prize

(24). Johnson made him a partner in 1851 and thus the

fi rm of Johnson and Matthey was fi nally established

in that year (17, 27). It was very largely Matthey who

transformed the fi rm from a largely laboratory-based

enterprise into a fully commercial business.

Johnson and Matthey were elected Fellows of the

Royal Society in 1846 and 1879 respectively; Johnson’s

election was supported by Michael Faraday amongst

others. Faraday had many connections with Johnson

and, in particular, Matthey (28). Faraday mentions

having ingots of platinum, which he describes as

“this beautiful, magnifi cent and valuable metal” in his

celebrated lecture-demonstration ‘On Platinum’ at the

Friday Discourse at the Royal Institution in Albemarle

Street on 22nd February 1861. He acknowledged

“Messrs. Johnson and Matthey, to whose great kindness

I am indebted for these ingots…” (29). Matthey

published a number of papers, mainly in mining

journals, but a key one concerns ‘The Preparation

Fig. 3. A commemorative medal for Queen Victoria’s coronation in 1838. A number of these medals were struck by the Royal Mint in platinum



in a State of Purity of the Group of Metals Known as

the Platinum Series and Notes upon the Manufacture

of Iridio-Platinum’. This presented a new method of

refi ning the platinum group metals (pgms) in which

lead was used to remove rhodium and iridium (30).

The “New Oxford Dictionary of National Biography”

has articles on Johnson (14) and Matthey (25).

Obituaries of Johnson (31, 32), William Cock (33) and

George Matthey (34) were published; McDonald (12)

has established that both the Johnson obituaries (31,

32) were written by George Matthey, albeit in edited

forms. The full original version has been given (12).

Sir William Crookes was probably the author (22) of

Cock’s obituary (33).

Early Collaborations of Johnson, Matthey and the Chemical SocietyPercival Johnson (listed as of 38 Mecklenburgh

Square) appears in the list of the original members

of the Chemical Society of London in 1841, together

with other famous names (4). He was one of the

early members of the Council of the Society, serving

from 1842–1844 (Michael Faraday joined him on the

Council in 1843) (3, 5). William Cock also appears on

the list of founder members of 1841 (4) and was one

of the few who gathered informally, prior to the offi cial

formation of the Society, to consider setting up such an

institution. He served on the Council of the Society in

1845 (3), giving in that year a specimen of palladium to

the Society’s Museum. In 1868 the Society established

a Faraday medal and this was, for its fi rst six issues, cast

in palladium, donated by Johnson Matthey. An item in

the Society’s minutes says that “a letter was read from

Messrs. Johnson and Matthey containing an offer to

present to the Society an amount of palladium to form

the Faraday medals for the next ten years of the value

of £200. The offer was accepted and a vote of thanks to

Messrs. Johnson and Matthey carried by acclamation”

(3). The fi rst six recipients of this palladium medal

(later medals were cast in bronze after the palladium

had run out) were all still-famous chemists: Jean-

Baptiste Dumas, Stanislao Cannizzarro, August Wilhelm

von Hofmann, Charles-Adolphe Wurtz, Hermann von

Helmholtz and Dmitri Mendeleev (3).

George Matthey was prominent in the Society:

he joined in 1873 and served on its Council from

1877–1878 (3). He was present at the Jubilee dinner

of the Society on 25th February 1891 (at which eleven

courses, fi ve wines, brandy and port were served) and

gave a speech after the dinner in his capacity as Prime

Warden of the Goldsmiths’ Company. In the afternoon

preceding the dinner there was an exhibition at which

Matthey showed samples of all six pgms and other

related objects, including a platinum snuff-box made

by Percival Johnson in 1816 and used by Johnson until

his death (3).

The Royal Society of Chemistry in the Twentieth Century In 1972 the process of unifi cation began of the Chemical

Society, the Royal Institute of Chemistry (established

1877), the Faraday Society (established 1903) and the

Society of Analytical Chemistry (established 1874).

The Queen signed a Royal Charter for the new Royal

Society of Chemistry (RSC) on 15th May 1980 (9). That

and subsequent periods saw continued collaboration

with Johnson Matthey, as the following examples show.

The Badge of Offi ce of the President of the RSC

(Figure 4) was originally presented in 1979 to the

President of the Royal Institute of Chemistry (35) and

(a) (b)Fig. 4. (a) The badge worn by the President of the Royal Society of Chemistry. It was inherited from the Royal Institute of Chemistry and modifi ed to carry the name of the RSC; (b) The badge is in the form of a spoked wheel, with the standing fi gure of Joseph Priestley depicted in enamel. The rim of the wheel is gold and the twelve spokes are of non-tarnishable metals with catalytic importance: palladium, nickel, titanium, iridium, niobium, tungsten, platinum, molybdenum, tantalum, rhodium, zirconium and cobalt



the materials for it made and donated by Johnson

Matthey. The fi rm’s Chief Chemist at that time, A. R.

Powell FRS (1894–1975) (37), gave a detailed account

of the fabrication of this unique and remarkable

object (38). In the centre is an enamelled medallion

of Joseph Priestley, set within a hexagon to symbolise

benzene. In the circular rim of gold surrounding

the medallion are set, like spokes in a wheel, twelve

metals of catalytic importance. Four pgms mark the

cardinal points (north is palladium, south platinum,

east iridium and west is rhodium); in a clockwise

direction after palladium lie nickel and titanium; after

iridium there are niobium and tungsten; after platinum

we have molybdenum and tantalum; and fi nally after

rhodium lie zirconium and cobalt. The synthetic

fi bre ribbon of nylon, viscose and cellulose acetate is

dyed with mauveine, discovered by Sir William Perkin

(1838–1907) in 1856 (35, 36, 38).

Collaborations in the Twentieth and Twenty-First CenturiesIn 2001 Johnson Matthey received the fi rst RSC

National Historic Chemical Landmark award (Figure 5); it was unveiled at the Johnson Matthey Technology

Centre in Sonning Common, UK, on 21st March

2001, for “Pioneering Work in Platinum research…….

which led to the development of car exhaust catalysts

and the design of platinum-based, anti-cancer drugs”

(39). The manufacture of the fi rst autocatalysts is

also commemorated by a plaque at the company’s

manufacturing premises in Royston, UK (Figure 6). The company has sponsored or co-sponsored a

number of RSC events. Among these, the triennial

International Conferences on Platinum Group Metals

meetings from 1981 to 2002 were a major feature. They

were sponsored jointly by the Dalton Division of the

RSC and Johnson Matthey and brought together many

experts on pgm chemistry, dealing in particular with

aspects of organometallic, catalytic and coordination

chemistry. These were held in July at the following

universities and from 1981 were reviewed in Platinum

Metals Review (references given in parentheses):

Bristol, 1981 (40)

Edinburgh, 1984 (41)

Sheffi eld, 1987 (42)

Cambridge, 1990 (43)

St. Andrews, 1993 (44)

York, 1996 (45)

Nottingham, 1999 (46)

Southampton, 2002 (47)

A more recent meeting was held at York University

on 30th November 2011 to mark the 250th anniversary

of the birth of Smithson Tennant (1761–1815),

discoverer of osmium and iridium (48), sponsored by

the RSC and Johnson Matthey Catalysts.

Fig. 6. A plaque commemorating the manufacture of autocatalysts by Johnson Matthey in Royston, UK

Fig. 5. The fi rst Royal Society of Chemistry National Historic Chemical Landmark award at Johnson Matthey Technology Centre, Sonning Common, UK



In 2008 Johnson Matthey sponsored the new

biennial RSC Lord Lewis Prize, awarded “for distinctive

and distinguished chemical or scientifi c achievements,

together with signifi cant contributions to the

development of science policy” (49). The fi rst awardee

was Lord Robert May of Oxford, FRS, OM (born in

1938), President of the Royal Society from 2000 to

2005, former Government Chief Scientifi c Advisor,

Professor of Zoology at the University of Oxford and

Fellow of Merton College. In 2010 the Prize went to Sir

John Cadogan CBE, FRS (born in 1930), formerly Chief

Scientist at the BP Research Centre and President of

the RSC from 1982–1984. The most recent winner, in

2012, was Sir David King FRS (born in 1939), from

2000–2007 the Government’s Chief Scientifi c Advisor

and the founding Director (2008–2012) of the Smith

School of Enterprise and Environment at the University

of Oxford.

Other joint RSC–Johnson Matthey projects have

included a book and workshop on teaching of pgm

separations created in 1998 (50). Teachers spent two

to three days at the Johnson Matthey Technology

Centre in Sonning Common, UK, with the late Phil

Smith of the RSC at the invitation of David Boyd,

Technology Manager at the Centre. Boyd gave a series

of presentations and workshops on the chemistry,

extraction, refi ning and uses of platinum. These were

turned into teaching aids, with a variety of exercises,

games, questions and experiments.

Johnson Matthey also partnered with the RSC on its

‘Faces of Chemistry’ initiative, a series of short videos

aimed at bringing to life careers in industry for young

people (51). Johnson Matthey scientists explain the

chemistry of pgm-based emission control catalysis

in three short fi lms, which were made available via

website and social media links from 2011.

The company also contributed materially to the

RSC Roadmap objectives (‘Chemistry for Tomorrow’s

World’) prepared in 2009 (52). Dr David Prest,

Managing Director for the European Region in the

fi rm’s Emission Control Technologies division and a

member of the RSC Council, chaired the steering group

– a cross section from industry and academia – which

prepared the Roadmap. The aim of their report was to

identify the role of the chemical sciences in helping

to solve major global challenges. The Roadmap was

developed via expert workshops and extensive online

consultations; many challenges were identifi ed, with

specifi c objectives with timescales of up to 15 years.

In 2010 Dr Martyn Twigg, then Chief Scientist of the

fi rm, won the RSC Applied Catalysis award “for his

pivotal and innovative role in creating new catalysts

and catalytic processes for use in the automotive

industry” (53) and in 2012 Dr Thomas J. Colacot, of

Johnson Matthey Catalysis and Chiral Technologies,

USA, won the same award “for exceptional

contributions to the development and availability of

ligands and catalysts crucial for the advancement of

metal-catalysed synthetic organic chemistry” (54, 55).

Thus Johnson Matthey and the RSC have

collaborated over many years, continuing into

the twenty-first century, making use of the firm’s

expertise in chemistry and catalysis, with particular

emphasis on their unrivalled experience with the

precious metals.

ConclusionsThis article has sought to show that Percival Johnson

and George Matthey, in effect the founders of Johnson

Matthey Plc, were closely associated with the Chemical

Society (of which Johnson was a founder and Matthey

a prominent member) since its inception in 1841 and

that this tradition has been continued to the present

with Johnson Matthey Plc and the Royal Society of

Chemistry.

AcknowledgementsIt is a pleasure to thank David Allen and Pauline

Meakins from the RSC for their help; as well as David

Prest, David Boyd, Sally Jones, Haydn Boehm and

Richard Seymour from Johnson Matthey; and Martyn

Twigg, formerly of Johnson Matthey, for their help in

providing some of the source material for this article.

References 1 W. H. Brock, Ambix, 1967, 14, (2), 133

2 C. Hamlin, ‘Warington, Robert (1807–1867), Chemist’, in “New Oxford Dictionary of National Biography”, Oxford University Press, Oxford, UK, 2004, Volume 57, pp. 423–424

3 R. Warington, “The Jubilee of The Chemical Society of London. Record of the Proceedings Together with an Account of the History and Development of the Society 1841–1891”, Harrisons and Sons, London, UK, 1896, p. 1, 115

4 Anon., Proc. Chem. Soc., Lond., 1842, 1, A001

5 Anon., Mem. Chem. Soc., Lond., 1841, 1, B001–B008

6 T. S. Moore and J. C. Philip, “The Chemical Society 1841–1941: A Historical Review”, Chemical Society, London, UK, 1947

7 D. A. Arnold, “The History of Burlington House”, Royal Society of Chemistry, London, UK, 1992: http://www.rsc.org/AboutUs/History/bhhist.asp. (Accessed on 14th February 2013)



8 P. Schmitt and O. Hopkins, “Burlington House: a Brief History”, Royal Academy of Arts, London, UK, 2010: http://static.royalacademy.org.uk/secure/fi les/architecture-guide-fi nal-785.pdf (Accessed on 14th February 2013)

9 D. H. Whiffen and D. H. Hey, “The Royal Society of Chemistry: the First 150 Years”, Royal Society of Chemistry, London, UK, 1991

10 D. McDonald, “The Johnsons of Maiden Lane”, Martins Publishers, London, UK, 1964

11 D. McDonald and L. B. Hunt, “A History of Platinum and its Allied Metals”, Johnson Matthey, London, UK, 1982

12 D. McDonald, “Percival Norton Johnson: The Biography of a Pioneer Metallurgist”, Johnson Matthey, London, UK, 1951

13 W. P. Griffi th, Platinum Metals Rev., 2003, 47, (4), 175

14 I. E. Cottington, ‘Johnson, Percival Norton (1792–1866), Metallurgist’, in “New Oxford Dictionary of National Biography”, Oxford University Press, Oxford, UK, 2004, Volume 30, p. 293

15 P. Johnson, Phil Mag., 1812, 40, (171), 3

16 D. McDonald, Platinum Metals Rev., 1962, 6, (3), 112

17 D. McDonald, Platinum Metals Rev., 1967, 11, (1), 18

18 H. Davy, Phil. Trans. R. Soc. Lond., 1817, 107, 45

19 H. Davy, Phil. Trans. R. Soc. Lond., 1817, 107, 77

20 L. B. Hunt, Platinum Metals Rev., 1979, 23, (1), 29

21 A. J. B. Robertson, Platinum Metals Rev., 1975, 19, (2), 64


23 W. J. Cock, Mem. Chem. Soc., Lond., 1841, 1, 161


25 I. E. Cottington, ‘Matthey, George (1825–1913), Refi ner and Metallurgist’, in “New Oxford Dictionary of National Biography”, Oxford University Press, Oxford, UK, 2004, Volume 32, p. 372

26 H. Gay, Notes Rec. R. Soc., 2008, 62, (1), 51

27 History, Johnson Matthey: http://www.matthey.com/about/history.htm (Accessed on 14th February 2013)

28 I. E. Cottington, Platinum Metals Rev., 1991, 35, (4), 222

29 M. Faraday, Chem. News, 1861, 3, 136

30 G. Matthey, Proc. R. Soc. Lond., 1878, 28, (190–195), 463

31 Anon., J. Chem. Soc., 1867, 20, 392

32 Anon., Proc. R. Soc. Lond., 1867, 16, xxiii

33 Chem. News, 1899, 80, 287

34 T. K. Rose, J. Chem. Soc., Trans., 1914, 105, 1222; W. Crookes, Chem. News, 1913, 107, 96

35 RSC – The President’s Badge of Offi ce: http://www.rsc.org/AboutUs/History/badge.asp (Accessed on 14th February 2013)

36 The 13-Metal Medal – Periodic Table of Videos, YouTube: http://www.youtube.com/watch?v=D5_zdap8ycE (Accessed on 14th February 2013)

37 G. Raynor, Biogr. Mems Fell. R. Soc., 1976, 22, 306

38 A. R. Powell, J. Proc. R. Inst. Chem., 1949, 73, Part VI, 476

39 ‘First National Historic Chemical Landmark Recognises Impact of Pioneering Work in Platinum Research’, RSC News Release, 16th March, 2001: http://www.rsc.org/images/Platinumlandmarkpressrelease_tcm18-18976.pdf (Accessed on 14th February 2013)

40 L. B. Hunt and B. A. Murrer, Platinum Metals Rev., 1981, 25, (4), 156

41 B. A. Murrer, Platinum Metals Rev., 1984, 28, (4), 168

42 B. A. Murrer, G. G. Ferrier and R. J. Potter, Platinum Metals Rev., 1987, 31, (4), 186

43 C. F. J. Barnard, Platinum Metals Rev., 1990, 34, (4), 207

44 O. J. Vaughan, Platinum Metals Rev., 1993, 37, (4), 212

45 A. Fulford, Platinum Metals Rev., 1996, 40, (4), 161

46 C. F. J. Barnard and W. Weston, Platinum Metals Rev., 1999, 43, (4), 158

47 J. Evans, Platinum Metals Rev., 2002, 46, (4), 165

48 R. N. Perutz, Platinum Metals Rev., 2012, 56, (3), 190

49 Lord Lewis Prize, RSC: http://www.rsc.org/ScienceAndTechnology/Awards/LordLewisPrize/Index.asp (Accessed on 14th February 2013)

50 “Learning About Materials: Three Workshop Exercises”, eds. E. Lister and C. Osborne, The Royal Society of Chemistry, London, UK, 1998

51 Faces of Chemistry Videos – Catalysts – Learn Chemistry, RSC: http://www.rsc.org/learn-chemistry/resource/res00000378/faces-of-chemistry-video-catalysts (Accessed on 14th February 2013)

52 Chemistry for Tomorrow’s World, RSC Roadmap, RSC: http://www.rsc.org/ScienceAndTechnology/roadmap/index.asp (Accessed on 14th February 2013)

53 Applied Catalysis Award 2010 Winner, RSC: http://www.rsc.org/ScienceAndTechnology/Awards/AppliedCatalysisAward/2010winner.asp (Accessed on 14th February 2013)

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55 S. Coles, Platinum Metals Rev., 2012, 56, (4), 219

The AuthorBill Griffi th is an Emeritus Professor of Chemistry at Imperial College (IC), London, UK. He has much experience with the platinum group metals, particularly ruthenium and osmium. He has published over 270 research papers, many describing complexes of these metals as catalysts for specifi c organic oxidations. He has written eight books on the platinum metals, and is currently writing, with Hannah Gay, a history of the 170-year old chemistry department at IC. He is responsible for Membership at the Historical Group of the Royal Society of Chemistry.



SAE 2012 World CongressVehicular emissions control highlights of the annual Society of Automotive Engineers (SAE) international congress


Reviewed by Timothy V. Johnson

Corning Environmental Technologies, Corning Incorporated, HP-CB-2-4, Corning, NY 14831, USA


The annual SAE Congress is the vehicle industry’s

largest conference and covers all aspects of

automotive engineering. The 2012 congress took

place in Detroit, USA, from 24th–26th April 2012. There

were upwards of a dozen sessions focused on vehicle

emissions technology, with most of these on diesel

emissions. More than 70 papers were presented on this

topic. In addition, there were two sessions on gasoline

engine emissions control with eight papers presented.

Attendance was up relative to the previous year, with

most sessions having perhaps 100 attendees, but some

had more than 200.

This review focuses on key developments from the

conference related to platinum group metals (pgms)

for both diesel and gasoline engine emissions control.

Papers can be purchased and downloaded from

the SAE website (1). As in previous years, the diesel

sessions were opened with a review paper of key

developments in both diesel and gasoline emissions

control from 2011 (2).

Lean NOx TrapsThe lean NOx trap (LNT) is currently the leading

deNOx concept for smaller lean-burn (diesel and

direct injection gasoline) passenger cars and is

of interest in applications with limited space or in

which urea usage is diffi cult. The deNOx effi ciency is

nominally 70–80%, much lower than that of the next

generation selective catalytic reduction (SCR) system

at >95% and the pgm usage is high (~8–12 g for a 2 l

engine). As a result, efforts are focused on improving

effi ciency while reducing pgm loadings. Only two

papers on LNTs were reported this year, much reduced

from previous years.

Katsuo Suga et al. (Nissan Motor Co Ltd, Japan)

used a selective pgm deposition process to enhance

platinum dispersion (3). The concept is to use a

surfactant to preferentially apply the Pt to the ceria

rather than to the alumina in the washcoat. Upon

ageing, the grain growth of Pt is greatly constrained

by the small size of the CeO2 grains, Figure 1. Usage

of pgm is cut by 50% without compromise in NOx

emissions. The researchers have also identifi ed that



the NOx desorption rate is considerably slower

than either adsorption or catalyst reactions at low

temperatures. The NOx desorption rate appears to be

increased by enhancing contact with CeO2 and baria,

the NOx trapping material. Work is continuing to verify

the effect.

Diesel Particulate Filters Although diesel particulate fi lters (DPFs) have been

in commercial production for original equipment

manufacturer (OEM) application for more than 10

years, there is still much optimisation activity in the

fi eld. Papers were offered on DPF regeneration and

several papers were presented on next generation DPF

substrates.

Contrary to light-duty diesel applications, wherein

system architecture and operating conditions

necessitate burning of the collected soot using mostly

thermal means at temperatures of about 600ºC, in

heavy-duty applications most (or all) of the soot

is burned passively using nitrogen dioxide (NO2)

generated in a pgm-based diesel oxidation catalyst

(DOC) and in the catalysed fi lter. Kenneth Lee Shiel

et al. (Michigan Technological University, USA)

quantifi ed this effect for ultra-low sulfur diesel (ULSD)

fuel and biodiesel blends (5). They loaded the fi lters

to about 2 g l–1 soot in a controlled fashion and then

introduced exhaust gas with the desired composition

and temperature to measure oxidation of the soot

with the NO2. They found that soot generated by

burning biodiesel oxidised slightly more slowly than

that from ULSD fuel, contradicting other studies

which have shown enhanced reactivity for biodiesel

soot in thermal regeneration. The Arrhenius plot did

not take into account the possibility of lowered DOC

activity, which can occur with biodiesel usage due to

more severe ash poisoning and thermal degradation.

Interestingly, the investigators quantifi ed the internal

generation of NO2 in the catalysed fi lter, wherein

NO2 fi rst passes through and reacts with the soot;

the resulting nitric oxide (NO) is oxidised back to

NO2 in the underlying catalyst and recycled back

for another round of soot oxidation. Recycling rates

were quite low at temperatures less than 300ºC, but

were very high (each NO molecule recycled three to

four times) at 450ºC.

Carl Justin Kamp et al. (Massachusetts Institute of

Technology, USA) (6) looked at the recycling of the

NO molecule, among other phenomena, in catalysed

fi lters in an entirely different way – they used a novel

‘focused beam ion milling’ technique to vaporise

away layers of material, ending up with a clean

cross-section of the substrate, washcoat, catalyst,

ash and soot. Figure 2 shows one such image. There

are voids between the soot and the catalyst that are

likely formed by the back diffusion of NO2 generated

by the catalyst. Other images show metal oxide ash

(from wear and burning lubricant oil) coating the

catalyst, but mostly not interfering with this recycling

phenomenon. Curiously, images were shown of ash

agglomerates measuring 20 μm in diameter that

mostly consisted of relatively large voids.

Ageing

Ageing

Conventional catalyst:

New concept catalyst:Pt

CeO2

Al2O3

Pt

CeO2 Al2O3

Fig. 1. Platinum is preferentially deposited on small ceria grains to minimise grain growth upon ageing of a new concept NOx trap catalyst (3)

Catalyst

Substrate

Soot

1 m

Fig. 2. Cross-section of the soot-catalyst layer in a platinum-catalysed diesel particulate fi lter made possible by a new ion milling technique (6)



Particulate oxidation catalysts (POCs) are a

cross between a DPF and a DOC wherein the soot

is trapped by turbulence mechanisms, forcing

particles to make contact with the Pt-catalysed

fi lter. POCs are a leading approach to particulate

emissions control in developing countries because

they do not require active regeneration. However,

these countries might not have low-sulfur fuel. Piotr

Bielaczyc (BOSMAL Automotive R&D Institute Ltd,

Poland) et al. (7) looked at the effects of fuel sulfur

on the performance of these devices. Although the

dry soot coming from the engine was the same in

all tests, the total particulate matter (PM) coming

from the engine increased with increasing levels

of sulfate. Between 20 h and 40 h of operation the

fi ltration effi ciency using a high sulfur fuel (365 ppm)

dropped by about 10% across the particle size range,

while that of a clean (sulfur-free) fuel changed very

little. The loss of effi ciency seen in the high-sulfur

fuel is likely due to the reduced availability of NO2

for cleaning and maintaining the fi lter effi ciency,

since NO2 generation in the DOC is hampered by the

presence of sulfur.

An important emerging trend is to coat DPFs with

an SCR catalyst as a way of consolidating parts and

getting the SCR closer to the turbocharger for faster

heating. Friedemann Schrade et al. (IAV GmbH,

Germany) (8) showed that when soot is on the Cu-zeolite

coated fi lter, the change in NO2 levels across the

soot layer caused by soot oxidation can impact SCR

performance. If the NO2 level going into the fi lter is

higher than ideal for the ‘fast’ SCR reaction, the soot

can improve performance. Conversely, if the NO2 level

is at or below the optimum 50% (of total NOx) level,

the soot can impair the SCR performance.

Diesel Oxidation Catalysts DOCs are generally catalysed with platinum and/

or palladium. They play two primary roles in

commercial emissions control systems: (a) to

oxidise hydrocarbons (HCs) and carbon monoxide,

either to reduce emissions coming from the engine

or to create exothermic heat used to regenerate a

DPF; and (b) to oxidise NO to NO2, which is required

to continuously oxidise soot on a DPF and/or to

enhance the SCR deNOx reactions, particularly at

low temperatures.

Ageing of DOCs is a critical phenomenon to

understand. It can impact HC emissions, DPF

regeneration and SCR performance. Junhui Li et al.

(Cummins Inc, USA) (9) retrieved several fi eld-aged

DOCs from in-use vehicles, sectioned them and studied

the ageing characteristics of the segments. As shown

in Figure 3, irreversible ageing caused different types

of deterioration. Catalyst samples cut from the rear of

the DOC had a higher NO light-off temperature than

those taken from the front. The opposite was true for

HC (propene) oxidation, wherein the rear parts had

a lower light-off temperature. The front catalysts were

aged primarily by ash contamination, while the back

catalysts were generally thermally aged. The overall

light-off characteristics of the catalyst deteriorated due

to both effects as the mileage increased. The authors

also reported reversible deterioration caused by HC

Rear

100 120 140 160 180 200

ReferenceFront

310

290

270

250

230

210

190

170

Propene lightoff, T50, ºC

NO

ligh

toff

, T25

, ºC

Fig. 3. NO and hydrocarbon (propene) light-off properties for samples taken from the front and rear of fi eld-aged platinum-based diesel oxidation catalysts. The reference catalyst was laboratory aged (9)



and sulfur poisoning, which could be removed with a

thermal treatment.

A new type of DOC was reported by Federico Millo

and Davide Fezza (Politecnico de Torino, Italy). They

added a low-temperature NOx adsorber material

(probably an alkaline earth oxide) to the DOC (10).

The material stores NOx (presumably as a nitrate) at

low temperatures and then releases the NOx at higher

temperatures when the downstream SCR catalyst is

operative. The adsorber aged substantially, but could

still provide signifi cantly better NOx removal than an

SCR-only confi guration. This ‘passive NOx adsorber’

(PNA) concept is being developed by Cary Henry et al.

(Cummins Inc, USA) and Howard Hess et al. (Johnson

Matthey Inc, USA) with quite impressive results (11).

Gasoline Emissions ControlCatalytic gasoline emissions control has been

commercialised for more than 35 years and the three-

way catalyst (TWC) for more than 30 years. Yet, it is still

evolving and showing signifi cant improvements. Since

the mid-1990s, when the TWC was perhaps in its third

generation, emissions have dropped by more than 95%

and pgm loading is down by upwards of 70% of what it

was then. The progress is still continuing.

For example, Yoshiaki Matsuzono et al. (Honda

R&D Co, Japan) and Takashi Yamada et al. (Johnson

Matthey Japan Inc) described a new layered catalyst

for improving the performance of both close-coupled

and underbody catalysts (13). The improvements cut

pgm usage by 75% while meeting the new California

Low Emission Vehicle III, Super Ultralow Emission

Vehicle – 30 mg mile–1 non-methane HC+NOx (LEV

III SULEV30) standard. The close-coupled catalyst is

layered with higher activity Pd and a lower activity

oxygen storage capacity (OSC) on the top, to better

withstand phosphorous poisoning and to achieve

better HC conversion. The catalyst demonstrates that

Pd-only catalysts can have application for the lowest

emissions applications. The underbody catalyst utilises

a zirconia-based OSC, allowing 50% less Rh to be used

versus the current version of the catalyst.

System design and calibration are signifi cant

contributors to lowering emissions from gasoline

vehicles. Douglas Ball and David Moser (Umicore

Autocat Inc, USA) (14) benchmarked fi ve of the cleanest

gasoline engine vehicles on the market with a variety of

hardware calibration strategies, including port-fueled

and direct injection, with and without secondary air,

and with different injection timings, engine speeds

and air:fuel ratios. The light-off strategies used various

combinations of high idle speed, aggressive ignition

retard, secondary air and split injections. All designs

achieved catalyst light-off during idle before the fi rst

hill in the test cycle. Secondary air was not necessarily

needed, but helped the catalyst heat to 950ºC in the fi rst

idle. Only 500ºC was reached in the same time without

secondary air. Turbocharged direct injection engines

use split injection, secondary air and late injection to

aid cold start. The investigators ran emissions tests to

help estimate what volume of catalyst will be needed

to meet the new California regulations. Figure 4

shows the case for a highly calibrated, port-fuel injected,

naturally aspirated 2.0 l engine without secondary air.

100

49

35

21

14

10

Catalyst volume, l0 0.5 1 1.5 2 2.5 3

LEV70 Target

LEV50 Target

SULEV30 Target

SULEV20 Target

Non

-met

hane

hyd

roca

rbon

s +

NO

x (m

g m

ile–1

)

Relative pgm loading

1.33

1.25

1.17

1.08

1.00

Fig. 4. Estimated required amount of pgm catalyst to achieve various emissions levels on a 2.0 l port-injection fuelled engine without secondary air (14)



Approximately 2 l of catalyst will be needed to achieve

the SULEV 30 target, compared with about 2.5 l of

catalyst to achieve the same result on a 2.4 l engine

with secondary air.

In an entirely different approach to evaluating pgm

loadings and emissions, Michael Zammit (Chrysler

Group LLC, USA) et al. (15) changed the distance from

the engine of a close-coupled TWC and measured

the emissions. They made estimates of the increased

pgm loadings to offset the increased distance while

keeping the emissions the same: an additional 37–50 mg

Pd per cm of distance from the engine.

To meet the new gasoline particle number

regulations of the light-duty Euro 6 regulation in 2017,

there is much interest in gasoline particulate fi lters

(GPFs). Early testing was done with uncatalysed fi lters,

but current evaluations use a TWC coating on the

fi lter. Joerg Michael Richter et al. (Umicore Autocat

Luxembourg) (16) evaluated two different coated

confi gurations with identical total pgm loadings. In

one confi guration the pgm was distributed evenly

between the close-coupled TWC and the GPF; in

another confi guration, the close-coupled catalyst was

optimised by zone-coating the Pd so that 80% of it is

on the front half. The investigators found that the NOx

emissions dropped by 20% in the fi rst coated GPF

confi guration compared to the baseline confi guration

without a GPF. With an optimised zone coating on

the close-coupled catalyst, 6% less pgm was used

compared to the baseline, NOx emissions remained

at the low level, but CO emissions were reduced by

30% compared to the other GPF confi guration. The

researchers reported that the TWC on the GPF aided

fi lter regeneration. No fuel penalty was observed when

the GPF was applied.

ConclusionWork is continuing on utilising Pt and other precious

metals more effectively to meet tightening tailpipe

emission regulations and reduce costs. Examples

highlighted in this Congress review include the more

effi cient use of Pt in LNTs by distributing it preferentially

on the CeO2 portion of the washcoat. In other work, Pt

was applied to a DPF resulting in the enhancement of

soot burn by NO2 by three or four times at 450ºC due

to the recycling of the NOx molecule in the vicinity

of the soot layer. Soot oxidation by NO2 was found to

be adversely impacted by sulfur in fuel and this could

impair the performance of POCs . The functionality

of Pt in fi eld-aged DOCs was impaired by ash in the

front portions, adversely impacting HC oxidation, and

by thermal ageing in the back, affecting NO oxidation.

The pgm loading of TWCs could be cut by 75% by

layering the catalyst, placing higher activity Pd and a

lower activity oxygen storage catalyst in the top layer.

Also, more is being learned on whole system design,

such as the effects of catalyst placement, turbocharging,

secondary air and fuel injection strategies, and the

impacts that these factors have on catalyst loadings.

Finally, this Congress featured catalysed GPFs for the

fi rst time, showing better system performance if some

pgm was moved from the close-coupled catalyst to

the GPF.

References 1 SAE International: http://www.sae.org/ (Accessed on

29th January 2013)

2 T. V. Johnson, ‘Vehicular Emissions in Review’, SAE Int. J. Engines, 2012, 5, (2), 216

3 K. Suga, T. Naito, Y. Hanaki, M. Nakamura, K. Shiratori, Y. Hiramoto and Y. Tanaka, ‘High-Effi ciency NOx Trap Catalyst with Highly Dispersed Precious Metal for Low Precious Metal Loading’, SAE Paper 2012-01-1246

4 Y. Tsukamoto, H. Nishioka, D. Imai, Y. Sobue, N. Takagi, T. Tanaka and T. Hamaguchi, ‘Development of New Concept Catalyst for Low CO2 Emission Diesel Engine Using NOx Adsorption at Low Temperatures’, SAE Paper 2012-01-0370

5 K. L. Shiel, J. Naber, J. Johnson and C. Hutton, ‘Catalyzed Particulate Filter Passive Oxidation Study with ULSD and Biodiesel Blended Fuel’, SAE Paper 2012-01-0837

6 C. J. Kamp, A. Sappok and V. Wong, ‘Soot and Ash Deposition Characteristics at the Catalyst-Substrate Interface and Intra-Layer Interactions in Aged Diesel Particulate Filters Illustrated Using Focused Ion Beam (FIB) Milling’, SAE Paper 2012-01-0836

7 P. Bielaczyc, J. Keskinen, J. Dzida, R. Sala, T. Ronkko, T. Kinnunen, P. Matilainen, P. Karjalainen and M. J. Happonen, ‘Performance of Particle Oxidation Catalyst and Particle Formation Studies with Sulphur Containing Fuels’, SAE Paper 2012-01-0366

8 F. Schrade, M. Brammer, J. Schaeffner, K. Langeheinecke and L. Kraemer, ‘Physico-Chemical Modeling of an Integrated SCR on DPF (SCR/DPF) System’, SAE Paper 2012-01-1083

9 J. Li, T. Szailer, A. Watts, N. Currier and A. Yezerets, ‘Investigation of the Impact of Real-World Aging on Diesel Oxidation Catalysts’, SAE Paper 2012-01-1094

10 F. Millo and D. Vezza, ‘Characterization of a New Advanced Diesel Oxidation Catalyst with Low Temperature NOx Storage Capability for LD Diesel’, SAE Paper 2012-01-0373



11 C. Henry, A. Gupta, N Currier, M. Ruth, H. Hess, M. Naseri, L. Cumaranatunge and H.-Y. Chen, ‘Advanced Technology Light Duty Diesel Aftertreatment System’, US Department of Energy 2012 Directions in Engine-Effi ciency and Emissions Research (DEER) Conference, Dearborn, Michigan, USA, 16th–19th October, 2012

12 K. Ishizaki, N. Mitsuda, N. Ohya, H. Ohno, T. Naka, A. Abe, H. Takagi and A. Sugimoto, ‘A Study of PGM-Free Oxidation Catalyst YMnO3 for Diesel Exhaust Aftertreatment’, SAE Paper 2012-01-0365

13 Y. Matsuzono, K. Kuroki, T. Nishi, N. Suzuki, T. Yamada, T. Hirota and G. Zhang, ‘Development of Advanced and Low PGM TWC System for LEV2 PZ EV and LEV3 SULEV30’, SAE Paper 2012-01-1242

14 D. Ball and D. Moser, ‘Cold Start Calibration of Current PZEV Vehicles and the Impact of LEV-III Emission Regulations’, SAE Paper 2012-01-1245

15 M. Zammit, J. Wuttke, P. Ravindran and S. Aaltonen, ‘The Effects of Catalytic Converter Location and Palladium Loading on Tailpipe Emissions’, SAE Paper 2012-01-1247

16 J. M. Richter, R. Klingmann, S. Spiess and K.-F. Wong, ‘Application of Catalyzed Gasoline Particulate Filters to GDI Vehicles’, SAE Paper 2012-01-1244

The ReviewerTimothy V. Johnson is Director – Emerging Regulations and Technologies for Corning Environmental Technologies, Corning Incorporated, USA. Dr Johnson is responsible for tracking emerging mobile emissions regulations and technologies and helps develop strategic positioning via new products.



“Complex-shaped Metal Nanoparticles: Bottom-Up Syntheses and Applications”Edited by Tapan K. Sau (International Institute of Information Technology, Hyderabad, India) and Andrey L. Rogach (City University of Hong Kong, Hong Kong), Wiley-VCH Verlag & Co KGaA, Weinheim, Germany, 2012, 582 pages, ISBN: 978-3-527-33077-5, £125.00, €178.80, US$200.00


Reviewed by Laura Ashfi eld

Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH, UK

Email: ashfi [email protected]

Introduction“Complex-shaped Metal Nanoparticles: Bottom-Up

Syntheses and Applications” offers a comprehensive

review of shaped metal nanoparticles through

synthetic strategies, theoretical modelling of growth,

discussion of properties and present and future

applications. The book is brought together by editors

Tapan K. Sau (International Institute of Information

Technology, Hyderabad, India) and Andrey L. Rogach

(Department of Physics and Materials Science at the

City University of Hong Kong). Between them, they

draw on their considerable expertise in the synthesis of

metal and semiconductor nanoparticles, spectroscopy,

photonics and applications of nanomaterials, to

combine 16 chapters from a large number of specialist

authors. This review will cover the majority of the book,

which refers in the main to noble metal particles, with

the exception of a few chapters which are specifi cally

related to non-platinum group metal (pgm) materials

and are therefore beyond the scope of this review.

The fi eld of nanoparticle preparation has enjoyed

an explosion in interest in the last decade as new

applications exploiting the novel physical, electronic

and optical properties of the particles have been

discovered. The properties of nanoparticles are highly

dependent on their morphology and thus, a vast

number of academic articles have been published

tackling the subject of the synthesis of specifi c shapes

of nanomaterials. “Complex-shaped Metal Nanoparticles:

Bottom-Up Syntheses and Applications” aims to bring

together this research in one volume giving a sound

understanding of the general principles, with copious

references to more detailed research papers if required

and looking towards potential future applications.

Practical AspectsThe book opens with the most substantial chapter,

written by the editors, which gives a more general



introduction to complex-shaped noble metal

nanoparticles and is an essential read for those less

familiar with the subject. The brief discussion on

the classifi cation of different shaped nanoparticles

and accompanying fi gure of transmission electron

microscopy (TEM) images (Figure 1) serves to

emphasise the breadth of this topic. The synthesis

methodologies are introduced by the means of

reduction, with a heavy emphasis on chemical

reduction but also including electrochemical,

photochemical and biochemical routes. It does

omit other methods such as sonochemical and

hydrothermal reduction, but gives references to

alternative sources that cover these.

The chapter provides a useful introduction to

topics such as the use of hard templates, for example

aluminium oxide porous membranes, and soft

templates, for example micelles, to control the growth

of the particles. It also covers galvanic replacement

and seed-mediated synthesis. Many of these topics are

discussed in greater detail in subsequent chapters. In

addition to synthesis, the chapter also briefl y reviews

the many analytical methods that are commonly

used to characterise nanoparticles and discusses

the pros and cons of each method. It goes on to

address the mechanisms of morphology evolution

with comprehensive references to the academic

literature, for example, the growth of branched

platinum nanoparticles from twinned seed crystals or

the role of the common growth directing surfactant,

cetyltrimethylammonium bromide (CTAB), in the

formation of gold nanorods. The editors are pleasingly

frank about the limitations of the synthetic methods

and emphasise the need for post-synthesis separation

due to the prevalence of polydisperse particles in

many of the preparations. The chapter concludes

with an outlook on where research is lacking and

knowledge needs to be improved in order to progress

the applications for shaped nanoparticles.

A more in depth look at templating techniques is

described in the following chapter by Chun-Hua

Cui and Shu-Hong Yu (University of Science and

Technology of China). Templating covers a variety

of techniques including galvanic displacement,

such as the formation of platinum nanotubes from

the treatment of silver nanowires with platinum

acetate, the use of the porous membrane template

anodic aluminium oxide for the electrodeposition

of palladium nanowires, hard templates, such as

lithographically produced patterns or soft templates,

such as CTAB micelles.

Na Tian et al. (Xiamen University, China) provide a

well set out chapter on high surface energy nanoparticles

and their use in electrocatalysis. Nanoparticles with a

Fig. 1. TEM and SEM images of one-, two- and three-dimensional noble metal nanoparticles: (a) nanorods; (b) nanoshuttles; (c) nanobipyramids; (d) nanowires; (e) a nanotubule; (f) triangular nanoplates; (g) nanodiscs; (h) nanoribbons; (i) nanobelts; (j) nanocubes; (k) nanotetrapods; (l) and (m) star-shaped nanoparticles; (n) a nanohexapod; and (o) a nanocage (Reproduced with permission from Wiley-VCH)

(a)

1D

2D

3D

20 nm100 nm

100 nm 200 nm

100 nm 500 nm 1 μm

1 μm

100 nm 500 nm 100 nm 50 nm500 nm

(b) (c) (d) (e)

(f) (g) (h) (i)

(j) (k) (l) (m)(n)

(o)

500 nm

[111]

100 nm



high surface energy have an increased proportion of

active surface atoms, with obvious advantages in fuel

cells, electrooxidation of ethanol and other catalytic

applications. The pgm nanoparticles have a face-

centred cubic structure and under thermodynamic

equilibrium conditions are enclosed by low energy

facets {111} giving an octahedral or tetrahedral

shape. The authors describe electrochemical and wet

chemistry routes to alternative high energy shapes --

concave hexaoctahedrons, 5-fold twinned nanorods,

rhombic dodecahedrons and many more. They

provide a very useful table including pictures of the

shapes, the indices of their facets and references to the

literature.

Chapter 9, written by Christophe Petit and Caroline

Salzemann (Université Pierre et Marie Curie, Paris,

France) and Arnaud Demortiere (Argonne National

Laboratory, USA), is specifi c to platinum and palladium

nanoparticles, bringing together some of the more

general principles covered earlier in the book. It

illustrates the complexity of controlling the numerous

variables involved in defi ning particle morphology.

The authors compare the use of alkylamine capping

agents in the Brust and reverse micelle synthesis

methods, resulting in faceted platinum nanocrystals

and polycrystalline worms, respectively. They go on to

discuss the effect of reaction conditions, for example

the timing of capping agent addition or the presence

of dissolved gasses, on the resultant particle shape.

Platinum rods, cubes or tripods can be generated

by using a nitrogen atmosphere; in the presence

of hydrogen, platinum nanocubes are formed. The

chapter is completed by a short discussion on self-

assembled supercrystals, for example square-based

pyramidal or triangular superlattices made up of

truncated platinum nanocubes (Figure 2).

This leads nicely into a chapter on ordered and

non-ordered porous superstructures written by Anne-

Kristin Herrmann (Technische Universität Dresden,

Germany) et al. These have applications in a variety of

areas including gold substrates for surface-enhanced

Raman spectroscopy and ordered hollow palladium

spheres for use as catalysts in the Suzuki reaction. The

authors cover techniques including the use of artifi cial

opals or polystyrene spheres as templates, which can

be removed by acid etching leaving metal nanoparticle

shells. Biotemplates and non-ordered templates, such

as aerogels and hydrogels, are also discussed.

TheoryChapters 6--8 cover the theoretical aspects of complex-

shaped nanoparticles. Tulio C. R. Rocha (Fritz-Haber-

Institut der Max-Planck-Gesellschaft, Germany) et al.

discuss Monte Carlo simulations of growth kinetics with

an emphasis on defects, such as stacking faults and twin

planes, using the synthesis of shaped silver particles as

an illustration. Vladimir Privman (Clarkson University,

USA) looks at the modelling of nucleation and growth

and its application to shape selection and control of

the morphology of growth on surfaces. Amanda S.

Barnard (Commonwealth Scientifi c and Industrial

Research Organisation (CSIRO), Materials Science and

Engineering, Australia) takes a thermodynamic rather

than a kinetic approach with the emerging technique

of thermodynamic cartography. This involves mapping

the thermodynamically preferred structure within

specifi ed parameters such as temperature, pressure or

chemical environment.

Fig. 2. SEM images of supercrystals of truncated platinum nanocubes: (a) superlattice of pyramidal shape; (b) ensemble of pyramidal supercrystals on a substrate; (c) superlattice of triangular shape; and (d) ensemble of triangular supercrystals on a substrate (Reproduced with permission from Wiley-VCH)

(a)

(b)

(c)

(d)

5 μm

50 μm

20 μm

3 μm



No text on nanoparticles would be complete

without a section on surface plasmons and optical

responses. This is provided by Cecilia Noguez and

Ana L. González (Universidad Nacional Autónoma de

México, Mexico) in Chapter 11. It is quite a theoretical

chapter, illustrated by numerous equations, which at

fi rst appear a little daunting to the synthetic chemist.

However, the chapter provides a useful discussion

on how surface plasmon resonances are sensitive to

particle shape.

ApplicationsChapters 12 to 16 take a more detailed look at the

applications for complex-shaped nanoparticles. The

order of these chapters does appear to be a little

haphazard with chapters on biomedical applications

interspersed with other topics but as the book is

designed as a reference to be dipped into it does

not detract too much from the overall experience.

In Chapter 12 Thomas A. Klar (Johannes-Kepler-

Universität Linz, Austria and Center for NanoScience

(CeNS), Germany) and Jochen Feldmann (Ludwig-

Maximilians-Universität München, Germany) introduce

fl uorophore-metal interactions and their application

in biosensing. It begins by going through the

theories behind the subject, before moving on to the

applications, such as ion sensing or immunoassays,

but is written in an understandable way for those new

to the topic. The chapter would benefi t from some

concluding remarks on future trends in this area.

Chapter 13 deals with surface-enhanced Raman

spectroscopy (SERS) and is written by Frank

Jäckel and Jochen Feldmann (Ludwig-Maximilians-

Universität München). It gives a good overview of the

subject without going into too much detail, and gives

references to further reading. The authors clearly

emphasise the effect of particle morphology in SERS

and compare different particle shapes, in keeping

with the aims of this publication. The following

chapter, written by Alexander O. Govorov et al. (Ohio

University, USA) moves back to bioapplications and

the photothermal effect of plasmonic nanoparticles.

It is mainly concerned with the theory of the

plasmonic photothermal effect with a small section

on applications and although it is of interest in the

more general context of nanoparticle applications, it

is not in keeping with the main theme of this book --

complex-shaped nanoparticles.

Jun Hui Soh (Institute of Bioengineering and

Nanotechnology, Singapore) and Zhiqiang Gao

(National University of Singapore) discuss the role

of metal nanoparticles in biomedical applications in

Chapter 15, covering subjects from diagnostics and

imaging to therapy. Some of these topics are discussed

in more detail in the preceding chapters, but this

chapter gives a well-written overview of all aspects

of biomedical applications. The only criticism is the

lack of real-world examples, as the references are all

based on academic literature. The fi nal chapter deals

with thermoelectric materials, which are generally

semiconductor materials.

SummaryIn conclusion “Complex-shaped Metal Nanoparticles:

Bottom-Up Syntheses and Applications” is an

extremely useful reference, whether the reader is

interested in synthesis, application or theory of

complex-shaped nanoparticles. Although there is

some repetition between chapters written by different

authors this serves to give the reader a choice of the

depth to which they wish to explore the subject and

I would recommend it as an informative resource to

anyone from students to experienced researchers.

The book clearly shows the potential for use of noble

metals in a broad spectrum of applications, including

catalysis, fuel cells, sensors, diagnostics and targeted

drug delivery. It becomes obvious that more research

into the reliable production of shaped nanoparticles

would be highly benefi cial.

The Reviewer Laura Ashfi eld received her DPhil in Inorganic Chemistry from the University of Oxford, UK, in 2005 and subsequently joined Johnson Matthey Technology Centre, Sonning Common, UK, where she is a Principal Scientist. Her work centres around the synthesis of nanomaterials with controlled morphology for a range of applications.

“Complex-shaped Metal Nanoparticles: Bottom-Up Syntheses and Applications”



Crystallographic Properties of RutheniumAssessment of properties from absolute zero to 2606 K


John W. Arblaster

Wombourne, West Midlands, UK


The crystallographic properties of ruthenium at

temperatures from absolute zero to the melting point at

2606 K are assessed following a review of the literature

published between 1935 and to date. Selected values of

the thermal expansion coeffi cients and measurements

of length changes due to thermal expansion have been

used to calculate the variation with temperature of the

lattice parameters, interatomic distances, atomic and

molar volumes and densities. The data is presented in

the form of Figures, Equations and Tables.

This is the sixth in a series of papers in this Journal on

the crystallographic properties of the platinum group

metals (pgms), following two papers on platinum

(1, 2) and one each on rhodium (3), iridium (4) and

palladium (5). Ruthenium exists in a hexagonal close-

packed (hcp) structure (Pearson symbol hP2) up to

the melting point which is a secondary fi xed point on

ITS-90 at 2606 ± 10 K (6).

The thermal expansion is represented by fi ve sets

of lattice parameter measurements, those of Owen

and Roberts (7, 8) (from 323 K to 873 K), Hall and

Crangle (9) (from 799 K to 1557 K), Ross and Hume-

Rothery (10) (from 1793 K to 2453 K), Schröder et

al. (11) (from 84 K to 1982 K) and Finkel’ et al. (12)

(from 80 K to 300 K) and one set of dilatometric

measurements, those of Shirasu and Minato (13)

(from 323 K to 1300 K). The measurements of

Hall and Crangle, Ross and Hume-Rothery and

Finkel’ et al. were only shown graphically with

actual data points as length change values being

given by Touloukian et al. (14). Because there is a

certain degree of incompatibility between the high-

temperature measurements, and those obtained at

low-temperature by Finkel’ et al., the high- and low-

temperature data were initially treated separately.

Available thermal expansion data covers the range

from 293.15 K to 2453 K with estimated values

below the lower limit whilst in the high-temperature

region the derived equations are extrapolated to the

melting point.



Thermal ExpansionHigh-Temperature RegionLength change values derived from the measurements

of Owen and Roberts (7, 8) and Ross and Hume-

Rothery (10) agree satisfactorily and were combined

to give Equations (i) and (ii) to represent the thermal

expansion from 293.15 K to the melting point. On the

basis ± 100L/L293.15 K Equation (i) for the a-axis has

an accuracy of ± 0.009 and Equation (ii) for the c-axis

an accuracy of ± 0.025. Crystallographic properties

derived from Equations (i) and (ii) are given in

Tables I and II.On the basis of the expression:

100 × (L/L293.15 K (experimental) – L/L293.15 K (calculated))

where L/L293.15 K (experimental) is the experimental length

change relative to 293.15 K and L/L293.15 K (calculated) is

the selected length change value, then length change

values derived from the measurements of Hall and

Crangle (9) deviate continuously from selected values

and both axes are 0.14 low at the experimental limit

1557 K. Above room temperature the a-axis values of

Schröder et al. (11) initially trend to be 0.080 low at

1300 K before increasing to 0.089 high at 1982 K. The

c-axis values behave similarly, initially trending to 0.072

low at 1100 K before increasing sharply to 0.35 high at

1982 K. The dilatometric measurements of Shirasu and

Minato (13) trend to 0.10 low. The deviations of these

three sets of values are shown in Figure 1.

Low-Temperature RegionThe lattice parameter measurements of Finkel’ et al.

(12), given as length change values by Touloukian

et al. (14), were fi tted to cubic Equations (v) and

(vi) for the a- and c-axes respectively. Derived

thermal expansion coeffi cients at 293.15 K of 6.5

× 10–6 K–1 for the a- axis and 11.5 × 10–6 K–1 for the

c-axis are notably higher than those derived from

Table I

High-Temperature Crystallographic Properties of Ruthenium

Temperature,

K

Thermal

expansion

coeffi cient,

a, 10–6 K–1

Thermal

expansion

coeffi cient,

c, 10–6 K–1

Thermal

expansion

coeffi cient,

avr, 10–6 K–1

Length

change,

a/a293.15 K

× 100, %

Length

change,

c/c293.15 K

× 100, %

Length

change,

avr/

avr293.15 K

× 100a, %

293.15 5.77 8.80 6.78 0 0 0

300 5.79 8.83 6.80 0.004 0.006 0.005

400 6.09 9.29 7.16 0.063 0.097 0.074

500 6.40 9.77 7.52 0.126 0.192 0.148

600 6.72 10.25 7.90 0.191 0.292 0.225

700 7.05 10.76 8.28 0.260 0.398 0.306

800 7.39 11.27 8.68 0.333 0.509 0.391

900 7.73 11.80 9.09 0.409 0.625 0.481

1000 8.09 12.34 9.51 0.488 0.746 0.574

1100 8.46 12.90 9.94 0.571 0.873 0.672

1200 8.83 13.47 10.38 0.658 1.006 0.774

1300 9.22 14.05 10.83 0.749 1.145 0.881

1400 9.61 14.65 11.29 0.844 1.291 0.993

1500 10.02 15.26 11.76 0.943 1.442 1.110

1600 10.43 15.88 12.24 1.046 1.600 1.231

1700 10.85 16.51 12.74 1.154 1.765 1.358

1800 11.28 17.16 13.24 1.266 1.936 1.489

(Continued)



Temperature,

K

Thermal

expansion

coeffi cient,

a, 10–6 K–1

Thermal

expansion

coeffi cient,

c, 10–6 K–1

Thermal

expansion

coeffi cient,

avr, 10–6 K–1

Length

change,

a/a293.15 K

× 100, %

Length

change,

c/c293.15 K

× 100, %

Length

change,

avr/

avr293.15 K

× 100a, %

1900 11.71 17.82 13.75 1.382 2.115 1.627

2000 12.16 18.49 14.27 1.503 2.300 1.769

2100 12.61 19.17 14.80 1.629 2.493 1.917

2200 13.08 19.86 15.34 1.760 2.693 2.071

2300 13.55 20.56 15.89 1.895 2.901 2.231

2400 14.03 21.28 16.44 2.036 3.117 2.396

2500 14.51 22.00 17.01 2.182 3.340 2.568

2600 15.01 22.74 17.58 2.333 3.571 2.746

2606 15.04 22.78 17.62 2.342 3.586 2.756

Table I (Continued)

Table II

Further High-Temperature Crystallographic Properties of Ruthenium

Temperature,

K

Lattice

parameter,

a, nma

Lattice

parameter,

c, nm

c/a

ratio

Interatomic

distance,

d1, nm

Atomic

volume,

10–3 nm3

Molar

volume,

10–6 m3

mol–1

Density,

kg m–3

293.15 0.27058 0.42816 1.5824 0.26502 13.574 8.174 12364

300 0.27059 0.42819 1.5824 0.26503 13.576 8.175 12363

400 0.27075 0.42857 1.5829 0.26524 13.604 8.193 12337

500 0.27092 0.42898 1.5834 0.26547 13.634 8.211 12310

600 0.27110 0.42941 1.5840 0.26570 13.666 8.230 12281

700 0.27128 0.42986 1.5845 0.26595 13.699 8.250 12251

800 0.27148 0.43034 1.5851 0.26620 13.734 8.271 12220

900 0.27169 0.43083 1.5858 0.26647 13.770 8.293 12188

1000 0.27190 0.43135 1.5864 0.26676 13.809 8.316 12154

1100 0.27213 0.43190 1.5871 0.26706 13.849 8.340 12118

1200 0.27236 0.43247 1.5878 0.26737 13.891 8.366 12082

1300 0.27261 0.43306 1.5886 0.26769 13.936 8.392 12043

1400 0.27286 0.43369 1.5894 0.26803 13.982 8.420 12003

1500 0.27313 0.43434 1.5902 0.26838 14.030 8.449 11962

1600 0.27341 0.43501 1.5911 0.26875 14.081 8.480 11919

1700 0.27370 0.43572 1.5919 0.26913 14.134 8.512 11874

1800 0.27401 0.43645 1.5929 0.26953 14.189 8.545 11828

(Continued)

a avr = average



Temperature,

K

Lattice

parameter,

a, nma

Lattice

parameter,

c, nm

c/a

ratio

Interatomic

distance,

d1, nm

Atomic

volume,

10–3 nm3

Molar

volume,

10–6 m3

mol–1

Density,

kg m–3

1900 0.27432 0.43722 1.5938 0.26995 14.247 8.580 11780

2000 0.27465 0.43801 1.5948 0.27038 14.307 8.616 11731

2100 0.27499 0.43883 1.5958 0.27083 14.369 8.653 11680

2200 0.27534 0.43969 1.5969 0.27130 14.434 8.692 11627

2300 0.27571 0.44058 1.5980 0.27178 14.502 8.733 11573

2400 0.27609 0.44150 1.5911 0.27229 14.572 8.776 11517

2500 0.27648 0.44246 1.6003 0.27281 14.646 8.820 11459

2600 0.27689 0.44345 1.6015 0.27335 14.722 8.866 11400

2606 0.27692 0.44351 1.6016 0.27338 14.727 8.869 11396

Table II (Continued)

100[L

/L29

3.15

K (e

xper

imen

tal)

– L

/L29

3.15

(cal

cula

ted)

]

0.36

0.31

0.26

0.21

0.16

0.11

0.06

0.01

–0.04

–0.09

–0.14

Ref. (9), a-axisRef. (9), c-axisRef. (11), a-axisRef. (11), c-axisRef. (13)

300 800 1300 1800 Temperature, K

Fig. 1. The difference between length change values derived from the measurements of Hall and Crangle (9), Schröder et al. (11) and Shirasu and Minato (13)

Equations (i) and (ii) as given in Tables II and III and

indicate the degree of incompatibility between the

high- and low-temperature data. Various manipulations

of subsets of the low-temperature measurements

to try and reconcile the differences proved to be

unsatisfactory and the measurements of Finkel’ et al.

were rejected. Therefore in order to extrapolate

below room temperature Equations (i) and (ii) were

differentiated and derived values of the thermal

expansion coeffi cient relative to 293.15 K, *, were

converted to thermodynamic thermal expansion, ,

using = */(1 + L/L293.15 K). The values obtained

a a = d2



Table III

Low-Temperature Crystallographic Properties of Ruthenium

Temperature,

K

Lattice

parameter,

a, nma

Lattice

parameter,

c, nm

c/a

ratio

Interatomic

distance,

d1, nm

Atomic

volume,

10–3 nm3

Molar

volume,

10–6 m3

mol–1

Density,

kg m–3

0b 0.27028 0.42742 1.5814 0.26462 13.520 8.142 12414

10 0.27028 0.42742 1.5814 0.26462 13.520 8.142 12414

20 0.27028 0.42743 1.5814 0.26462 13.520 8.142 12414

30 0.27028 0.42743 1.5814 0.26462 13.520 8.142 12414

40 0.27028 0.42743 1.5814 0.26462 13.520 8.142 12413

50 0.27028 0.42744 1.5815 0.26462 13.521 8.142 12413

60 0.27028 0.42745 1.5815 0.26463 13.521 8.143 12412

70 0.27029 0.42746 1.5815 0.26464 13.522 8.143 12411

80 0.27030 0.42748 1.5815 0.26465 13.524 8.144 12410

90 0.27031 0.42750 1.5815 0.26466 13.525 8.145 12409

100 0.27031 0.42752 1.5816 0.26467 13.527 8.146 12407

110 0.27033 0.42755 1.5816 0.26468 13.529 8.147 12406

120 0.27034 0.42757 1.5816 0.26470 13.531 8.148 12404

130 0.27035 0.42760 1.5817 0.26471 13.533 8.150 12402

140 0.27036 0.42763 1.5817 0.26473 13.535 8.151 12400

150 0.27037 0.42766 1.5817 0.26475 13.537 8.152 12398

160 0.27039 0.42769 1.5818 0.26476 13.539 8.154 12396

170 0.27040 0.42772 1.5818 0.26478 13.542 8.155 12394

180 0.27041 0.42776 1.5819 0.26480 13.544 8.156 12391

190 0.27043 0.42779 1.5819 0.26482 13.547 8.158 12389

200 0.27044 0.42782 1.5820 0.26484 13.549 8.159 12387

210 0.27045 0.42786 1.5820 0.26485 13.552 8.161 12385

220 0.27046 0.42789 1.5820 0.26487 13.554 8.162 12382

230 0.27048 0.42793 1.5821 0.26489 13.557 8.164 12380

240 0.27050 0.42796 1.5821 0.26491 13.559 8.166 12377

250 0.27051 0.42800 1.5822 0.26493 13.562 8.167 12375

260 0.27053 0.42804 1.5822 0.26495 13.565 8.169 12373

270 0.27054 0.42807 1.5823 0.26497 13.567 8.170 12370

280 0.27056 0.42811 1.5823 0.26499 13.570 8.172 12368

290 0.27058 0.42815 1.5824 0.26501 13.573 8.174 12365

293.15 0.27058 0.42816 1.5824 0.26502 13.574 8.174 12364a

a = d2b Since all values below 293.15 K are estimated they are given in italics



at 293.15 K and over the range 300 K to 800 K at 50 K

intervals were then fi tted to Equations (iii) and (iv)

where the values of the specifi c heat used, Cp, are

given by Equation (vii). Equations (iii) and (iv) were

then extrapolated below the room temperature region

using specifi c heat values given in the Appendix in

order to represent the thermal expansion to absolute

zero, although a-axis thermal expansion coeffi cients

above 240 K were slightly adjusted in order to give a

smooth continuity with the high-temperature selected

values. Crystallographic properties derived from

Equations (iii) and (iv) are given in Tables III and IV.

There is the possibility of signifi cant uncertainty

in this procedure but it is noted that in comparison,

using the same procedure as for the high-temperature

data, the measurements of Finkel’ et al. (12) show a

maximum deviation of only 0.006 low at 80 K for the

a-axis and then converge towards the selected values.

For the c-axis, there is initially agreement with the

selected values and a maximum deviation of only

0.010 low at 220 K. These small differences would

actually suggest agreement between the high- and

low-temperature data; however, the fi tting procedure

is so sensitive that these differences represent

incompatibility. The low-temperature measurements

of Schröder et al. (11) are initially 0.027 low at 84 K

for the a-axis and then converge towards the selected

values, whilst for the c-axis the value is initially 0.026

low but there is agreement to better than 0.001 above

210 K.

Normally, as an alternative method of calculation,

Equations (iii) and (iv) would be fi tted to a series of

Table IV

Further Low-Temperature Crystallographic Properties of Ruthenium

Temperature,

K

Thermal

expansion

coeffi cient,

a, 10–6 K–1

Thermal

expansion

coeffi cient,

c, 10–6 K–1

Thermal

expansion

coeffi cient,

avr, 10–6 K–1

Length

change,

a/a293.15 K

× 100, %

Length

change,

c/c293.15 K

× 100, %

Length

change, avr/

avr293.15 K

× 100, %

0a 0 0 0 –0.113 –0.172 –0.132

10 0.04 0.06 0.05 –0.113 –0.172 –0.132

20 0.09 0.16 0.12 –0.113 –0.172 –0.132

30 0.32 0.48 0.37 –0.112 –0.171 –0.132

40 0.70 1.07 0.83 –0.112 –0.171 –0.131

50 1.25 1.91 1.47 –0.111 –0.169 –0.130

60 1.85 2.82 2.17 –0.109 –0.167 –0.129

70 2.39 3.66 2.56 –0.107 –0.163 –0.126

80 2.88 4.40 3.39 –0.105 –0.159 –0.123

90 3.30 5.04 3.88 –0.102 –0.155 –0.119

100 3.66 5.58 4.30 –0.098 –0.149 –0.115

110 3.95 6.03 4.65 –0.094 –0.144 –0.111

120 4.20 6.42 4.94 –0.090 –0.137 –0.106

130 4.42 6.74 5.19 –0.086 –0.131 –0.101

140 4.60 7.02 5.40 –0.081 –0.124 –0.096

150 4.75 7.25 5.58 –0.077 –0.117 –0.090

160 4.88 7.44 5.73 –0.072 –0.109 –0.084

170 4.98 7.61 5.86 –0.067 –0.102 –0.079

180 5.08 7.76 5.97 –0.062 –0.094 –0.073

190 5.17 7.89 6.07 –0.057 –0.086 –0.067

200 5.25 8.01 6.17 –0.052 –0.079 –0.061

(Continued)



Temperature,

K

Thermal

expansion

coeffi cient,

a, 10–6 K–1

Thermal

expansion

coeffi cient,

c, 10–6 K–1

Thermal

expansion

coeffi cient,

avr, 10–6 K–1

Length

change,

a/a293.15 K

× 100, %

Length

change,

c/c293.15 K

× 100, %

Length

change, avr/

avr293.15 K

× 100, %

210 5.32 8.12 6.25 –0.046 –0.070 –0.054

220 5.38 8.22 6.33 –0.041 –0.062 –0.048

230 5.45 8.31 6.40 –0.036 –0.054 –0.042

240 5.50 8.40 6.47 –0.030 –0.046 –0.035

250 5.58 8.48 6.55 –0.024 –0.037 –0.029

260 5.63 8.56 6.61 –0.019 –0.029 –0.022

270 5.68 8.63 6.66 –0.013 –0.020 –0.016

280 5.71 8.70 6.71 –0.008 –0.011 –0.009

290 5.75 8.77 6.76 –0.002 –0.003 –0.002

293.15 5.77 8.80 6.78 0 0 0a Since all values below 293.15 K are estimated they are given in italics

Table IV (Continued)

spline fi tted equations; however as there are two axes

this could involve a signifi cant number of equations

and therefore the much simpler procedure has

been adopted of substituting values of Cp from the

Appendix into the equations.

The Lattice Parameter at 293.15 KThe values of the lattice parameters, a and c,

given in Table V represent a combination of those

values selected by Donohue (15) and more recent

measurements. Values originally given in kX units

were converted to nanometres using the 2010

International Council for Science: Committee on Data

for Science and Technology (CODATA) Fundamental

Constants (16, 17) conversion factor for CuK1, which

is 0.100207697 ± 0.000000028 whilst values given in

angstroms (Å) were converted using the default ratio

0.100207697/1.00202 where the latter value represents

the old conversion factor from kX units to Å. Lattice

parameter values were corrected to 293.15 K using the

values of the thermal expansion coeffi cient selected

in the present review. Density values given in Tables II and III were calculated using the currently accepted

atomic weight of 101.07 ± 0.02 (18) and an Avogadro

Table V

Lattice Parameter Values at 293.15 Ka

Authors (Year) Reference Original

temperature,

K

Original

units

Lattice

parameter, a,

corrected to

293.15 K, nm

Lattice

parameter, c,

corrected to

293.15 K, nm

Notes

Owen et al. (1935)

(18) 291 kX 0.27044 0.42818 (a)

Owen and Roberts (1936)

(7) 291 kX 0.27042 0.42819 (a)

Owen and Roberts (1937)

(8) 293 kX 0.27040 0.42819 (a)

(Continued)



Authors (Year) Reference Original

temperature,

K

Original

units

Lattice

parameter, a,

corrected to

293.15 K, nm

Lattice

parameter, c,

corrected to

293.15 K, nm

Notes

Ross and Hume-Rothery

(10) 303 Å 0.27042 0.42799 (a), (b)

Finkel’ et al. (1971)

(12) 293 Å 0.27062 0.42815 (a), (b)

Hellawell and Hume-Rothery (1954)

(19) 298 kX 0.27058 0.42817

Swanson et al. (1955)

(20) 300 Å 0.27059 0.42819

Hall and Crangle (1957)

(9) rtb Å 0.27058 0.42805

Anderson and Hume-Rothery (1960)

(21) 293 kX 0.27058 0.42814

Černohorský (1960)

(22) 295 Å 0.27059 0.42812

Savitskii et al. (1962)

(23) rt kX 0.27059 0.42819

Schröder et al. (1972)

(11) 284 Å 0.27056 0.42826

aSelected values for the present paper are: a = 0.27058 ± 0.00002 and 0.42816 ± 0.00007brt = room temperature

Notes to Table V

(a) For information only – not included in the average

(b) Lattice parameter values given by Touloukian et al. (14)

Table V (Continued)

constant (NA) of (6.02214129 ± 0.00000027) × 1023 mol–1

(16, 17). From the lattice parameter values at 293.15 K

selected in Table V as: a = 0.27058 ± 0.00002 nm

and c = 0.42816 ± 0.00007 nm, the derived selected

density is 12364 ± 3 kg m–3 and the molar volume is

(8.1743 ± 0.0018) × 10–6 m3 mol–1. In Tables II and III the interatomic distance d1 = (a2/3 + c2/4)½ and

d2 = a. The atomic volume is (√3 a2 c)/4 and the

molar volume is calculated as NA (√3 a2 c)/4 which

is equivalent to atomic weight divided by density.

Thermal expansion is avr = (2 a + c)/3 and length

change is avr/avr293.15 K = (2 a/a293.15 K + c/c293.15 K)/3

(avr = average).

SummaryBecause there is disagreement between the high-

and low-temperature measurements for ruthenium,

satisfactory thermal expansion data is only available

above 293.15 K with a novel approach being used to

extrapolate below this temperature to derive values

which must be considered to be tentative. Clearly

further measurements are required for this element.



High-Temperature Thermal Expansion Equations for Ruthenium (293.15 K to 2606 K)

a/a293.15 = –1.56642 × 10–3 + 4.93471 × 10–6 T + 1.34455 × 10–9 T 2 + 1.69158 × 10–13 T 3 (i)

c/c293.15 = –2.39045 × 10–3 + 7.52727 × 10–6 T + 2.06251 × 10–9 T 2 + 2.61425 × 10–13 T 3 (ii)

Low-Temperature Thermal Expansion Equations for Ruthenium (0 K to 293.15 K)

a (K–1) = Cp (1.92207 × 10–7 + 8.09046 × 10–11 T + 7.16082 × 10–6 / T) (iii)

c (K–1) = Cp (2.93088 × 10–7 + 1.24609 × 10–10 T + 1.09421 × 10–5 / T) (iv)

Thermal Expansion Equations Representing the Measurements of Finkel’ et al. (12)

a/a293.15 = –1.40337 × 10–3 + 3.25082 × 10–6 T + 4.63332 × 10–9 T 2 + 2.07266 × 10–12 T 3 (v)

c/c293.15 = –1.87652 × 10–3 + 3.44170 × 10–6 T + 2.91501 × 10–9 T 2 + 2.44946 × 10–11 T 3 (vi)

High-Temperature Specifi c Heat Equation (298.15 K to 2606 K)

Cp (J mol–1 K–1) = 23.1728 + 7.28378 × 10–3 T – 2.703021 × 10–6 T 2 + 1.50844 × 10–9 T 3 – 97572.6/T 2 (vii)

Appendix: Specifi c Heat Values for Ruthenium

Because of the large number of spline fi tted equations that would be required to conform to Equations

(iii) and (iv), a simpler approach is used for the non-cubic metals in that specifi c heat values are directly

applied to these equations. However this would require that the Table of low-temperature specifi c heat

values originally given by the present author (24) has to be more comprehensive and the revised Table is

given as Table VI. The high-temperature specifi c heat values corresponding to the above reference is given

as Equation (vii) and is derived by differentiating the selected enthalpy equation.

Table VI

Low-Temperature Specifi c Heat Values for Ruthenium

Temperature,

K

Specifi c

heat, J

mol–1 K

Temperature,

K

Specifi c

heat, J

mol–1 K

Temperature,

K

Specifi c

heat, J

mol–1 K

10 0.0438 50 3.682 130 17.130

15 0.0955 60 5.838 140 18.050

20 0.186 70 7.991 150 18.837

25 0.359 80 10.000 160 19.509

30 0.731 90 11.839 170 20.093

35 1.233 100 13.455 180 20.607

40 1.877 110 14.854 190 21.066

45 2.707 120 16.071 200 21.480(Continued)



Temperature,

K

Specifi c

heat, J

mol–1 K

Temperature,

K

Specifi c

heat, J

mol–1 K

Temperature,

K

Specifi c

heat, J

mol–1 K

210 21.857 250 23.047 290 23.889

220 22.200 260 23.277 293.15 23.950

230 22.514 270 23.490 298.15 24.046

240 22.796 280 23.693 300 24.071

Table VI (Continued)

References 1 J. W. Arblaster, Platinum Metals Rev., 1997, 41, (1), 12

2 J. W. Arblaster, Platinum Metals Rev., 2006, 50, (3), 118




6 R. E. Bedford, G. Bonnier, H. Maas and F. Pavese, Metrologia, 1996, 33, (2), 133

7 E. A. Owen and E. W. Roberts, Philos. Mag., 1936, 22, (146), 290

8 E. A. Owen and E. W. Roberts, Z. Kristallogr., 1937, A96, 497

9 E. O. Hall and J. Crangle, Acta Cryst., 1957, 10, Part 3, 240

10 R. G. Ross and W. Hume-Rothery, J. Less Common Met., 1963, 5, (3), 258

11 R. H. Schröder, N. Schmitz-Pranghe and R. Kohlhaas, Z. Metallkd., 1972, 63, (1), 12

12 V. A. Finkel’, M. Palatnik and G. P. Kovtun, Fiz. Met. Metalloved., 1971, 32, (1), 212; translated into English in Phys. Met. Metallogr., 1972, 32, (1), 231

13 Y. Shirasu and K. Minato, J. Alloys Compd., 2002, 335, (1–2), 224

14 Y. S. Touloukian, R. K. Kirby, R. E. Taylor and P. D. Desai, “Thermal Expansion: Metallic Elements and Alloys”, Thermophysical Properties of Matter, The TPRC Data Series, Vol. 12, eds. Y. S. Touloukian and C. Y. Ho, IFI/Plenum Press, New York, USA, 1975

15 J. Donohue, “The Structure of the Elements”, John Wiley and Sons, New York, USA, 1974

16 P. J. Mohr, B. N. Taylor and D. B. Newell, Rev. Mod. Phys., 2012, 84, (4), 1527

17 P. J. Mohr, B. N. Taylor and D. B. Newell, J. Phys. Chem. Ref. Data, 2012, 41, (4), 043109

18 E. A. Owen, L. Pickup and I. O. Roberts, Z. Kristallogr., 1935, A91, 70

19 A. Hellawell and W. Hume-Rothery, Philos. Mag. Ser. 7, 1954, 45, (367), 797

20 H. E. Swanson, R. K. Fuyat and G. M. Ugrinic, “Standard X-Ray Diffraction Powder Patterns”, NBS Circular Natl. Bur. Stand. Circ. (US) 539, 1955, IV, 5

21 E. Anderson and W. Hume-Rothery. J. Less Common Met., 1960, 2, (6), 443

22 M. Černohorský, Acta Cryst., 1960, 13, (10), 823

23 E. M. Savitskii, M. A. Tylkina and V. P. Polyakova, Zh. Neorgan. Khim., 1962, 7, (2), 439; translated into English in Russ. J. Inorg. Chem., 1962, 7, (2), 224

24 J. W. Arblaster, CALPHAD, 1995, 19, (3), 339

The AuthorJohn W. Arblaster is interested in the history of science and the evaluation of the thermodynamic and crystallographic properties of the elements. Now retired, he previously worked as a metallurgical chemist in a number of commercial laboratories and was involved in the analysis of a wide range of ferrous and non-ferrous alloys.



“Polymer Electrolyte Membrane and Direct Methanol Fuel Cell Technology”Edited by Christoph Hartnig (Chemetall GmbH, Germany) and Christina Roth (Institute for Applied Materials – Energy Storage Systems, Karlsruhe Institute of Technology, Germany), Woodhead Publishing Series in Energy, Woodhead Publishing Ltd, Cambridge, UK, 2012; Volume 1: Fundamentals and Performance of Low Temperature Fuel Cells, 436 pages, ISBN: 978-1-84569-773-0, £150.00, €180.00, US$255.00; Volume 2: In Situ Characterization Techniques for Low Temperature Fuel Cells, 524 pages, ISBN: 978-1-84569-774-7, £165.00, €200.00, US$280.00


Reviewed by Bruno G. Pollet

HySA Systems Competence Centre, SAIAMC, University of the Western Cape, Modderdam Road, Private Bag X17, Bellville 7535, Cape Town, South Africa


IntroductionThis book set covers polymer electrolyte membrane

fuel cells (PEMFCs) and direct methanol fuel cells

(DMFCs). It is aimed at novice readers as well as

experienced fuel cell scientists and engineers in this

area. There are 34 contributors in Volume 1 and 30 in

Volume 2, predominantly from Germany, with some

contributions from the UK, France, Denmark, Italy,

Switzerland, the USA and Canada. The editors are well

known for their research, work and contributions in

the fi elds of low-temperature fuel cell technology and

materials components characterisation. Dr Christoph

Hartnig is based at Chemetall GmbH and was formerly

Head of Research at both BASF Fuel Cell GmbH and

the Centre for Solar Energy and Hydrogen Research

(Zentrum für Sonnenenergie- und Wasserstoff-

Forschung Baden-Württemberg (ZSW)), Germany.

Professor Dr Christina Roth is Professor for Renewable

Energies at the Technische Universität Darmstadt and

Head of a Research Group at the Institute for Applied

Materials – Energy Storage Systems, Karlsruhe Institute

of Technology (KIT) in Germany.

Volume 1: “Fundamentals and Performance of Low Temperature Fuel Cells”Volume 1 consists of two parts. Part I is entitled

‘Fundamentals of Polymer Electrolyte Membrane and

Direct Methanol Fuel Cell Technology’, and Part II is

entitled ‘Performance Issues in Polymer Electrolyte

Membrane and Direct Methanol Fuel Cells’.

Fuels and MaterialsPart I consists of fi ve chapters. Chapter 1: ‘Fuels and Fuel

Processing for Low Temperature Fuel Cells’ deals with

the effects of fuel type and quality on low-temperature

fuel cell performance and degradation. The chapter



gives short overviews of fuel processing, fuel storage

methods and alternative sources of hydrogen. An

excellent diagram overview of fuel processing for

fuel cell systems (Figure 1) by Iain Staffell (Imperial

College, London, UK) (1) is given. Chapter 2: ‘Membrane

Materials and Technology for Low Temperature Fuel

Cells’ gives a very good overview of the most recent

investigations in PEM materials for low-temperature

PEMFCs with a section on PEM materials for high-

temperature applications. It reviews perfl uorosulfonic

acid PEMs and non-perfl uorinated PEMs including

sulfonic acid, phosphonic, heterocycle functionalised

and acid doped membrane materials. A short section

is specifi cally dedicated to the morphology and

microstructure of ionomer membranes.

ElectrocatalystsChapter 3: ‘Catalyst and Membrane for Low Temperature

Fuel Cells’ focuses on fuel cell electrocatalysis and

the importance of the type and loading of the

cathode catalyst. The current anode and cathode

catalyst loadings for low-temperature PEMFCs are ca.

0.2 mgPt cm–2 and 0.4 mgPt cm–2, respectively, with a

target for automotive applications of a total catalyst

loading of 0.2 mgPt cm–2 (with anode catalyst loading of

0.05 mgPt cm–2 and cathode catalyst loading of

0.15 mgPt cm–2) for a cell voltage of 0.85 V, assuming a

CO-free hydrogen supply. Figure 2 shows the evolution of

Pt loading and estimated fuel cell balance of plant from

2006 (2). Both carbonaceous and non-carbonaceous

electrocatalyst support materials are mentioned

MethodsNatural gas

Desulfuriser

Reformer

Shift reactor

CO removal

CO2 scrubber

Hydro-desulfurisation,

selective adsorption

Steam reforming, partial oxidation,

autothermal reforming

High-temperature (HT) and low-

temperature (LT) shift

Preferential oxidation, pressure swing adsorption,

methanisation

Soda lime adsorption, regenerative

amines, electrical swing adsorption

SOFC

PAFC

PEMFC

AFC

Output gas composition

95% CH4 , 4%

C2H

6 , 1% CO2

10% CO,10% CO2, 0.5–1% CH4

0.5–1% CO, 15% CO2

10 ppm CO, 15% CO2

10 ppm CO, 100 ppm CO2

Function

Remove the sulfur based odorants added to natural gas for safety reasons:

ZnO + H2S ZnS + H2OAl

25ºC

Catalytically process methane into hydrogen with steam and an absence of oxygen:

CH4 + H2O CO + 3H2Ni-Al/Pt-Pd

650–850ºC

Improve the hydrogen yield and reduce concentration of the waste carbon monoxide:

CO + H2O CO2 + H2Cu-Zn/Fe-Cr

350–450ºC (HT)175–300ºC (LT)

Reduce CO concentration to ppm levels:

CO + ½O2 CO2Pt-Ru/Rh-Al

150–200ºC

Reduce CO2 concentration to ppm levels:

CO2 + Ca(OH)2 CaCO3+ 25ºC H2O

Fig. 1. An overview of fuel processing for fuel cell systems (1) (Courtesy of Iain Staffell, University of Birmingham, UK, and Woodhead Publishing)



(including, for example, metal oxides (3)) for both

PEMFCs and direct methanol fuel cells (DMFCs).

The chapter also highlights some of the most

recent developments in anode and cathode catalysts

(including ultra-low Pt) used in low-temperature fuel

cells. These include core-shell and binary and ternary

alloy electrocatalysts – platinum alloyed with cobalt,

copper, iron, molybdenum, nickel and/or ruthenium.

The chapter also discusses new approaches in fuel

cell electrocatalysis research and development, for

example the reduction of the Pt content and the

investigation of Pt-free compounds (for example

Co and Fe incorporated in nitrogen macrocycle

structures) based upon either non-precious metals

or alloyed transition metals. However, the chapter

does not touch on advanced cathode catalysts such

as the famous 3M platinum nano-structured thin fi lm

(NSTF) (4), which is a bit of a disappointment. For

those who are interested in learning further about fuel

cell electrocatalysis, there are a number of additional

books which I would strongly recommend (4–6).

Gas Diffusion MediaChapter 4: ‘Gas Diffusion Media, Flow Fields and

System Aspects in Low Temperature Fuel Cells’ covers

the role and importance of gas diffusion media

(tefl onated/untefl onated woven and non-woven), fl ow

fi eld plate designs on performance and degradation

and system design criteria for low-temperature

applications. The chapter briefl y states characterisation

methods for gas diffusion layers, although it does not

highlight other ex situ characterisation methods for

bulk or contact resistance, surface morphology or fi bre

structure and mechanical strength measurements (7).

There is also little information on the possible thermal

conductivity effect of the microporous layer on cell

performance.

The chapter then broadly discusses the role of fl ow

fi eld design for both low-temperature PEMFC and DMFC

with some brief discussions around the importance

of fl ow fi eld plate material, especially its interaction

with the gas diffusion layer material under various

operating conditions and applications (7, 8). Perhaps

for completeness the authors could have added a short

section on ex situ characterisation and accelerated

ageing/accelerated stress tests for fl ow fi eld plate

materials. This chapter also discusses the importance

of the system layouts of the two low-temperature fuel

cells, i.e. balance of plant, including reactant supplies

and thermal management. For Chapter 4, perhaps

the section on system aspects of low-temperature

fuel cells could have been a separate chapter in the

book emphasising the correlation between the fl ow

fi eld plate design and material, the gas diffusion layer

material and the overall system design and layout.

Environmental AspectsChapter 5: ‘Recycling and Life Cycle Assessment of

Fuel Cell Materials’ focuses on the environmental

aspects of fuel, fuel cell components and fuel cell

stacks as well as recycling. The chapter highlights the

fact that pgms such as Pt, Pd and Rh are successfully

2015

2010

2009

2008

2007

2006

Year

0 0.2 0.4 0.6 0.8 1.0 1.2

US$30 kW–1 (US DOE target) 1 W cm–2

Key

Power density (W cm–2)Estimated balance of plant (US$ kW–1) (including assembly and testing)Platinum loading (mgPt cm–2) used in automotive PEMFC stacks at a cell voltage of 0.676 VPlatinum loading (gPt kW–1) used in automotive PEMFC stacks

Platinum loadings, gPt kW–1 or mgPt cm–2

US$51 kW–1

833 mW cm–2

US$61 kW–1

833 mW cm–2

US$94 kW–1

583 mW cm–2

US$73 kW–1

715 mW cm–2

US$108 kW–1 700 mW cm–2

Fig. 2. Evolution of platinum loadings and estimated fuel cell balance of plant (Reproduced from (2) by permission of Elsevier)



recycled from today’s vehicles (principally from

catalytic converters – modern vehicles may contain

around 1 g of Pt for petrol and around 8 g of Pt for

diesel (2)) and the technologies can be adopted to

recycle Pt from fuel cell systems. This chapter is very

interesting and well-written as recycling of fuel cell

components and systems and their impact on the

environment is often neglected, and a ‘zero-to-landfi ll’

approach is required in order to lead to long-term

cost savings. It also highlights that recycling in the fuel

cell manufacturing industry will become paramount

for mass-produced systems in which environmental

considerations will have to be taken into account

(for example, collection/separation systems, recycling

processes, component reuse, remanufacturability and

energy recovery). Life cycle assessment models of

fuels and fuel cell components are discussed in detail

and the standardised life cycle assessment protocol

(International Organization for Standardisation – ISO

14040 series) is briefl y mentioned.

Operation and AgeingPart II in Volume 1 consists of seven chapters:

Chapter 6: ‘Operation and Durability of Low

Temperature Fuel Cells’ gives an excellent overview

of the effects of low-temperature PEMFC operating

conditions (thermal, water and reactant management,

contamination types and levels and duty cycling) on

performance and durability (which is also correlated

to component material properties, their designs and

cycling abilities). The chapter highlights the major

degradation processes occurring in the pgm-based

cathode catalyst layer and PEM regions present for

all operating conditions and briefl y describes how

that degradation can be minimised, in turn increasing

performance and durability, by improving the overall

stack design at component material and operational

levels.

Chapter 7: ‘Catalyst Ageing and Degradation in

Polymer Electrolyte Membrane Fuel Cells’ focuses on

performance degradation of electrocatalysts affected

by the relatively harsh operating conditions within

low-temperature fuel cells and discusses catalyst

ageing mechanisms. For example, it explains the

three principal mechanisms attributed to the loss

of electrochemical surface area for pure Pt and Pt

alloys supported on carbon, i.e. dissolution (leading

to Pt redeposition or Pt precipitation), migration

with concomitant coalescence and detachment of

Pt nanoparticles from the carbonaceous support as

well as complete or incomplete carbon corrosion

of the support material. The discussion then focuses

on the main effects causing such mechanisms:

temperature, pH, anion types, water partial pressure,

Pt particle size and electrode potential variations

and for Pt alloy electrocatalysts, dealloying of the

non-precious metal (mainly transition metals as they

are not stable in acidic environments – for example

Pt-Co catalysts are known to exhibit poor performance

under intense cycling conditions). The chapter also

briefl y reviews ex situ and in situ catalyst degradation

characterisation methods with an emphasis on a very

useful, powerful and newly developed technique –

identical location transmission electron microscopy

(IL-TEM) – that was originally developed by the

chapter’s authors (Figure 3). The technique provides

(b)(a)

50 nm

50 nm

100 nm(c)

Fig. 3. Series of IL-TEM micrographs of platinum particles on a carbon support, showing: (a) Particle detachment; (b) Particle movement and agglomeration; and (c) Displacement of the carbon support under various harsh potential cycling conditions (Reproduced by permission of Woodhead Publishing)



insights into electrocatalyst stability on the nanoscale

level under various regimes and thus allows a direct

(visual) observation of the effect of electrochemical

treatments on carbon-supported high surface area

electrocatalysts (9).

Durability TestsChapter 8: ‘Degradation and Durability Testing of

Low Temperature Fuel Cell Components’ is well-

written and well-structured. It discusses accelerated

durability test protocols (ex situ and in situ) mainly

for the critical low-temperature PEMFC components

which are the PEM, the electrocatalyst and the

electrocatalyst carbonaceous support materials.

The chapter also briefl y covers the effect of fuel

contaminants on durability. Chapter 8 nicely

highlights the main publications dealing with

degradation and durability studies and protocols for

the membrane electrode assembly (MEA) and its

subcomponents.

Chapter 9 is a very good and systematic discussion

of the stochastic microstructure techniques for the

determination of transport property parameters as well

as the study of the effect of porous structure materials

upon transport behaviours within the critical PEMFC

catalyst layer, gas diffusion layer and microporous

layer regions.

ModellingChapter 10: ‘Multi-scale Modelling of Two-Phase

Transport in Polymer Electrolyte Membrane Fuel

Cells’ discusses in detail the pore network model and

the lattice Boltzmann model for the modelling of

two-phase fl ow in porous PEMFC materials such as

gas diffusion layers and catalyst layers. The chapter

describes how pore-scale information (for example,

microstructure, transport and performance) can be

useful for more predictive macroscopic scale-up.

Chapter 11, entitled ‘Modelling and Analysis of

Degradation Phenomena in Polymer Electrolyte

Membrane Fuel Cells’, is an excellent review of

the various available models describing PEMFC

degradation phenomena and mechanisms. The

chapter highlights the most important work on

the subject in the last 20 years and also briefl y

introduces pioneering work by, for example, Springer

et al. (Los Alamos National Laboratory, New Mexico,

USA) (10), Bernardi and Verbrugge (General Motors

Research and Environmental Staff, USA) (11) and

Antoine (Université de Genève, Switzerland) et al.

(12). This chapter also describes systematically and

comprehensively the various modelling approaches

to elucidate ageing mechanisms and their possible

predictions. The author also discusses the newly

developed transient, multi-scale and multi-physics

single cell model MEMEPhys® (13) and emphasises

the need to generate representative accelerated testing

methods in the fi eld.

Finally, Volume 1 ends with Chapter 12 entitled

‘Experimental Monitoring Techniques for Polymer

Electrolyte Membrane Fuel Cells’. This chapter

describes the various techniques and methods

employed for on-line and off-line logging, monitoring

and diagnosis of important fuel cell parameters (for

example, temperature, humidity, current distribution,

local pressure distribution and pressure drop) during

operation.

Volume 2: “In Situ Characterization Techniques for Low Temperature Fuel Cells”Volume 2 consists of three parts: Part I entitled

‘Advanced Characterization Techniques for Polymer

Electrolyte Membrane and Direct Methanol Fuel

Cells’, Part II entitled ‘Characterization of Water

and Fuel Management in Polymer Electrolyte

Membrane and Direct Methanol Fuel Cells’ and Part

III entitled ‘Locally Resolved Methods for Polymer

Electrolyte Membrane and Direct Methanol Fuel

Cell Characterization’. I thoroughly enjoyed reading

Volume 2 as it covers comprehensively the important

and main (in situ) techniques and methods currently

employed in characterising in detail MEA and MEA

subcomponents (fuel cell electrocatalyst, catalyst

layer, membrane and gas diffusion medium) as

well as water and fuel management. It would have

been very useful to have included a summary table

showing the in situ and ex situ characterisation

techniques which help to elucidate the degradation

mechanisms for all MEA components and water

and fuel management (including extended X-ray

absorption fi ne structure (EXAFS), IL-TEM, three-

dimensional (3D)-TEM, in situ X-ray tomography

(XRT), small angle X-ray scattering (SAXS), X-ray

adsorption near edge structure (Δμ XANES),

neutron radiography, neutron tomography, magnetic

resonance imaging, synchrotron radiography,

Raman spectroscopy, scanning electron microscopy

(SEM) and laser optical methods).

ConclusionsThis two-volume set presents a fairly comprehensive

and detailed review of low-temperature PEMFCs and

DMFCs and their in situ characterisation methods

by reviewing in detail their fundamentals and



performance as well as advanced in situ spectroscopic

techniques for their characterisation. I was impressed

by the content and breadth of this detailed work. There

are of course already books available covering similar

areas and there is some duplication between chapters

(for example, fuel cell descriptions), but this does not

detract from the overall experience. The book set also

highlights the key challenges for the commercialisation

of PEMFC-based systems, mainly related to life cycle

analysis of the overall systems and global research

and development efforts on materials development for

durability and long term operation.

This is a very informative work, especially with

regard to current progress on in situ characterisation

techniques (Volume 2). Although I was a little

disappointed at the lack of high-temperature PEMFC

information, I would defi nitely recommend this book

set for readers who are either experienced or new in

this exciting fi eld.

References 1 I. Staffell, ‘Fuel Cells for Domestic Heat and Power:

Are They Worth It?’, PhD Thesis, School of Chemical Engineering, University of Birmingham, UK, September 2009

2 B. G. Pollet, I. Staffell and J. L. Shang, Electrochim. Acta, 2012, 84, 235 and references therein

3 S. Sharma and B. G. Pollet, J. Power Sources, 2012, 208, 96

4 M. K. Debe, Nature, 2012, 486, (7401), 43

5 “Catalysis in Electrochemistry: From Fundamentals to Strategies for Fuel Cell Development”, eds. E. Santos and W. Schmickler, John Wiley & Sons, Inc, Hoboken, New Jersey, USA, 2011

6 “PEM Fuel Cell Electrocatalysts and Catalyst Layers: Fundamentals and Applications”, ed. J. Zhang, Springer-Verlag London Ltd, Guildford, Surrey, UK, 2008

7 A. El-kharouf and B. G. Pollet, ‘Gas Diffusion Media and Their Degradation’, in “Polymer Electrolyte Fuel Cell Degradation”, eds. M. M. Mench, E. C. Kumbur and T. N. Veziroglu, Elsevier Inc, Waltham, Massachusetts, USA, 2012, pp. 215-247

8 P. J. Hamilton and B. G. Pollet, Fuel Cells, 2010, 10, (4), 489

9 K. J. J. Mayrhofer, S. J. Ashton, J. C. Meier, G. K. H. Wiberg, M. Hanzlik and M. Arenz, J. Power Sources, 2008, 185, (2), 734

10 T. E. Springer, T. A. Zawodzinski and S. Gottesfeld, J. Electrochem. Soc., 1991, 138, (8), 2334

11 D. M. Bernardi and M. W. Verbrugge, J. Electrochem. Soc., 1992, 139, (9), 2477

12 O. Antoine, Y. Bultel and R. Durand, J. Electroanal. Chem., 2001, 499, (1), 85

13 A. A. Franco, ‘A Physical Multiscale Model of the Electrochemical Dynamics in a Polymer Electrolyte Fuel Cell – An Infi nite Dimensional Bond Graph Approach’, PhD Thesis, Université Claude Bernard Lyon-1, France, 2005

The ReviewerBruno G. Pollet FRSC recently joined Hydrogen South Africa (HySA) Systems Competence Centre at the University of the Western Cape as Director and Professor of Hydrogen and Fuel Cell Technologies. Pollet has extensive expertise in the research fi elds of PEMFC, fuel cell electrocatalysis and electrochemical engineering. Website: http://www.hysasystems.org/

“Polymer Electrolyte Membrane and Direct Methanol Fuel Cell Technology”, Volumes 1 & 2



Kunming–PM’20125th International Conference “Platinum Metals in the Modern Industry, Hydrogen Energy and Life Maintenance of the Future”


Reviewed by Mikhail Piskulov*

Johnson Matthey Moscow Offi ce, Ilyinka 3/8, Building 5, Offi ce 301, 109012 Moscow, Russia

*Email: [email protected]

Carol Chiu**

Johnson Matthey Technology Centre, Blounts Court, Sonning Common, Reading RG4 9NH, UK

**Email: [email protected]

The 5th international biennial conference in the series

“Platinum Metals in the Modern Industry, Hydrogen

Energy and Life Maintenance of the Future” was held

from 15th to 19th October 2012, in Kunming, China.

The conference was organised by the Kunming

Institute of Precious Metals under the patronage of

the International Organisation “Professor Ye. I. Rytvin

Foundation” and with the support of the Non-Ferrous

Metals Society of China and OJSC Supermetal, Russia.

The conference was attended by 125 participants from

seven countries.

The conference covered both production and a

wide range of applications of the platinum group

metals (pgms), including uses in the automotive,

electronics, glass, dental, jewellery, hydrogen and solar

energy sectors. The programme included 18 Plenary

Session reports and over 40 reports were published in

the conference proceedings.

The following main topics were covered during the

Plenary Sessions.

Structure Control of Noble Metal Nano- and MicroparticlesProfessor Nanfeng Zheng (Xiamen University,

China) gave a presentation on ‘Multilevel Control of

Noble Metal Nanostructures for Catalysis and Bio-

applications’. The presentation was focused on how

surface structure can optimise activity and stability

for surface-dependent catalysis (e.g. ammonia

synthesis and carbon monoxide (CO) oxidation) and

surface-dependent electrocatalysis (e.g. fuel cells).

There is a large difference in the surface energies

of platinum and palladium with different surface

crystal structures, and the dominant surface structure

affects catalytic activity. Small adsorbents (e.g. halides,

formaldehyde, carbon monoxide or amines) were

used to control the metal nanostructures to prepare

unique Pd and Pt nanocrystals. One of the examples

discussed was Pd hexagonal nanosheets. The edge

length of the hexagons increased with reaction time

while the thickness remained fi xed at 1.8 nm. It was

proposed that the dominant surface was {111}, which

gives improved electrocatalytic properties compared



with commercial Pd black as well as unique optical

and photothermal effects. One of the proposed

applications is in near infrared photothermal cancer

therapy. Many other types of pgm nanostructures have

also been synthesised by the CO adsorption method,

such as tetrapod nanocrystals, nanocubes and

octapods. In the oxidation of ethanol, the activity of Pt

octapods was measured to be four times higher than

Pt black or Pt on carbon.

Professor Xudong Sun (Northeastern University,

Shenyang, China) presented a paper on ‘Controllable

Synthesis of Dispersed Precious Metal Powders’ which

reviewed achievements and problems related to

preparation of dispersed precious metals powders

by chemical reduction, more specifi cally synthesis

of various morphologies, such as monodispersed

spheres, single crystalline particles and nanowires.

In addition to nanoparticles, microparticles of silver,

gold, silver-palladium alloy, ruthenium and tungsten

also have a wide range of commercial applications,

such as electrode pastes and catalysts. Microparticles

have two representative categories, dispersed

crystalline particles and monodispersed spherical

particles. Formation of dispersed crystalline particles

is explained by the LaMer model (Figure 1) which

assumes that nucleation and growth are separate. By

adjusting the nucleation rate, the resulting particle sizes

can be controlled. The nucleation rate is controlled

by the pH while agglomeration is avoided by a high

stabiliser concentration. Monodispersed spherical

particles are formed by nucleation and growth to

subunits from a supersaturated solution, followed

by aggregation of the subunits into monodispersed

spheres. The aggregation of primary particles is affected

by changes in the ionic strength or pH. The presenter

concluded that research on structure control of noble

metal microparticles is at least as important as that on

the corresponding nanoparticles.

Tatjana Buslaeva (Lomonosov Moscow University

of Fine Chemical Technology, Russia) presented

joint work with the University of Eastern Finland

on ‘The Synthesis of Catalytic Systems Based

on Nanocomposites Containing Palladium and

Hydroxycarbonates of Rare-Earth Elements’. For this

work yttrium and cerium hydroxycarbonates were

used as the support and Pd nanoparticles were

directly reduced from solution. Nanocomposites

Pd/Y(OH)CO3 and Pd/Ce(OH)CO3 were synthesised

using two methods: (a) simultaneous production

of a nanoscale substrate and immobilisation of Pd

nanoparticles on its surface; or (b) prior synthesis

of polyvinylpyrrolidone stabilised Pd nanoparticles

followed by their immobilisation on the nanosized

substrate surface. The new systems synthesised

demonstrated high conversion effi ciency and can be

used for homogeneous catalyst production.

Applications of the Platinum Group Metals Professor Zhuangqi Hu (Institute of Metal Research

of the Chinese Academy of Sciences, Shenyang,

China) explained the role of Ru in nickel-based single

crystal superalloys. Over the last few years there has

been increasing research on superalloy materials

due to their high mechanical strength and oxidation

resistance at elevated temperatures. Ni-based

superalloys are widely used in turbine blades found in

jet engines, ships and power plants. The blades operate

in the hottest part of the engine at temperatures around

1100ºC. The most recently discovered microstructure

of superalloys is the third generation single crystal. By

adding a refractory element, such as rhenium, strength

is enhanced. However, over addition or segregation

of Re causes topologically close packed (tcp) phase

precipitation which damages the continuity of the

microstructure, promotes crack initiation and leads

to a decrease in strength of the superalloy. To prevent

this, tests were made with Ru-free alloy and with

alloys containing 1.5% and 3% Ru additions. Cast

microstructure, structural evolution, tensility and

rupture properties and oxidation behaviour were

studied. It was noted that the addition of Ru suppressed

tcp phase formation and hence improved the creep

properties, so that Ru-containing superalloys could be

used even under higher temperature conditions. There

Critical limiting supersaturation

Rapid self-nucleation

Growth Solubility

Time

Cmax

Cmin

CsConc

entr

atio

n

I II III

Fig. 1. LaMer model of dispersed crystalline particle formation (Cmax = maximum concentration for nucleation, Cmin = minimum concentration for nucleation, Cs = concentration for solubility, I = prenucleation period, II = nucleation period, III = growth period) (Image courtesy of Professor Xudong Sun, Northeastern University, China)



was a strengthening effect on tensility, but no obvious

effect on stress rupture life, and a weakening effect on

heat/corrosion resistance. A higher oxidation rate was

also observed when the Ru-containing superalloys

were heated to 1000ºC or 1100ºC. The conclusion was

that in future Ru might play an important commercial

role in such superalloys.

Professor Yizhou Zhou (Institute of Metals Research

of the Chinese Academy of Sciences, Xi’an, China)

presented a paper entitled ‘Effects of Platinum on

the Micro-Segregation Behaviour and Phase Stability

in Nickel-Base Single Crystal Superalloys’. In addition

to the work on Ru discussed above, Pt has also

been examined as a potential alloying addition to a

third generation single crystal superalloy. However,

experimental work on such materials has shown

that the incipient melting point, solidus and liquidus

temperatures are decreased. Pt segregates to the

interdendritic region and intensifi es the segregation

of refractory elements such as Re and tungsten.

Formation of a tcp phase is also promoted under

extended thermal exposure at 1100ºC. Although Pt

additions enhance tensile strength at high temperature,

it is unable to enhance rupture life. It was concluded

that Pt additions to single crystal superalloys do not

have a benefi cial effect on phase stability.

Professor Guang Ma (Northwest Institute for Non-

Ferrous Metal Research, China) spoke on the topic of

Pd alloy membranes in hydrogen energy. Hydrogen

is an alternative energy source which could reduce

our dependence on fossil fuels in the future. For

many commercial applications hydrogen must be

purifi ed and the use of Pd-based alloy membranes

for purifi cation is very attractive. Pd-rare earth alloys

have improved hydrogen permeability compared to

other alloys used for this purpose (1). This is because

the rare earth elements not only expand the Pd lattice

but also readily adsorb hydrogen onto the membrane

surface. Hydrogen separation rates increase with

hydrogen permeability of the membrane. Improved

mechanical strength, heat resistance and hydrogen

diffusion rates, as well as the development of low cost

manufacturing routes, are seen as important research

and development targets for Pd-based hydrogen

separation membranes.

Wei Li (General Motors, USA) reported on such

issues as catalyst deactivation due to pgm sintering

and poisoning, recent trends in the use of pgms in

diesel catalysts (in particular the diesel oxidation

catalyst (DOC), lean NOx trap (LNT) and diesel

particulate fi lter (DPF)), different factors affecting

catalyst performance, and the impact of future global

emissions regulations on pgm usage in automotive

emissions control catalysts.

Junjun He (Sino-Platinum Metals Co Ltd, China)

presented a review of the metal–support interaction

in automotive catalysts. The support can improve the

dispersion of Pt, Pd and Rh and suppress the sintering

of the pgms at high temperatures. The pgms can also

enhance the redox performance and oxygen storage

capacity of the support. The presentation reviewed the

reaction phenomena and mechanism of pgms and

supports such as Al2O3 and CeO2-based composite oxides.

Vitaly Parunov (Moscow State University of

Medicine and Dentistry, Russia) made a report on the

biocompatibility of different denture materials based

on research carried out amongst 109 patients. The noble

metal-based alloys Plagodent and Palladent (fabricated

by Supermetal, Russia) showed the best results when

compared to other types of metal-based materials.

PGM Refi ning TechnologiesJoseph L. Thomas (Metals Recovery Technology Inc

(MRTI), USA) explained MRTI’s commercial precious

metal recovery technologies. Recently, four different

types of pgm-containing waste feedstock have been

treated:

(a) Pd was recovered from various supported Pd

catalysts (100–5000 ppm Pd) by chlorine leaching.

After addition of chlorine and polyamine resin, a

Pd-loaded polyamine composite resin (2) was

produced, while other metals (e.g. Ni, copper

and iron) remained in solution. The capacity

was 20 Mt per batch with a fi ve day cycle and a

recovery rate of 99% Pd.

(b) Pt, Pd or gold were recovered from Cu alloys

containing these metals. After adding Cu metal

to Pt, Pd or Au ores or spent catalysts, the mixture

was melted by induction to give the Cu alloy.

Then sodium chloride and chlorine gas were

added. The dissolved precious metals were then

reduced to insoluble solids and separated from

the solution.

(c) Pd, Pt, rhodium and Au were recovered from

spent autocatalysts. The reaction again involved

the addition of chlorine together with resin to

the autocatalysts. Only Pd, Pt, Rh and Au were

absorbed onto the resin while other metals,

including Group I and Group II chalcogens

and other transition metals, were not. The

metal resins were then burned to yield metal of

98–99% purity.



(d) The pgms were recovered from a complex

mixture of pgms and other transition metals. The

pgms were refi ned using a substituted quaternary

ammonium salt (2) giving more than 99.9% pgm

recovery with a typical purity of 99.97% to 99.99%

in six days. The procedure relied on precipitation,

fi ltration and washing and did not involve ion

exchange or solvent extraction. This is based

on the fact that only pgms will precipitate with

tetramethylammonium chloride. The reagent may

be recycled after use.

Professor Jinhui Peng (Kunming University of

Science and Technology, China) reviewed the recovery

of pgms from secondary resources using microwave

technology. This is believed to be more effi cient,

energy-saving and environmentally friendly than

conventional metallurgical process. Three different

approaches were discussed:

(a) Microwave-assisted leaching improved the yield

and process time for the recovery of pgms from

spent catalysts. After microwave heating at 600ºC

for 60 minutes, the leaching effi ciencies of Pd and

Rh were 99.8% and 97.4%, respectively (3).

(b) Microwave pyrolysis was used to recycle pgms

from waste printed circuit boards. The waste

circuit boards were initially crushed into small

pieces and microwave heated to decompose

organic compounds. Subsequent heating to

1100ºC allowed the pgms to be separated and

recovered.

(c) Microwave augmented ashing was used to reduce

the length of time required for the activation

process for recovery of Pt and Rh from scrap

fi rebricks from the glass industry.

Although microwave assisted pgm recovery was

still at the laboratory stage, it has potential to be a

next generation pgm refi ning technology due to its

environmental benefi ts.

Market Trends and the PGM IndustryMikhail Piskulov (Johnson Matthey Moscow,

Russia) reported on recent trends in industrial pgm

applications. It was noted that industrial applications

play an important role in the pgm markets,

accounting for 25–30% of the gross total demand for

Pt and Pd and close to 100% for such minor pgms

as Ru and Ir. In the last 10 years industrial demand

has been on the increase over the entire pgm range.

However, there is a constant need for new research

and development to fully explore and develop new

areas which can benefit from the unique properties

of pgms.

Alexander Andreev (Ekaterinburg Non-Ferrous

Metals Processing Plant, Russia) outlined in his paper

the role of Russia in the global pgm markets and the

problems faced by Russian exporters due to internal

regulations. Andreev estimates that in 2011, the

Russian share of global pgm supply amounted to 13%

(26 tonnes) Pt, 47% (108 tonnes) Pd and 8.9% (2.12

tonnes) Rh. However, the Russian share of world pgm

trade was much lower. The discrepancy was explained

by a lack of metal trading activities in Russia, compared

to the European and Asian markets, largely due to

concentration of demand (end users for sectors like

electronics and automotive) in these regions, but also

due to issues related to the limitations and shortcomings

of Russian customs and currency regulations.

Mariya Goltsova (Donetsk National Technical

University, Ukraine) presented the ‘Hydrogen

Civilization (HyCi) Doctrine’, which describes a vision

of sustainable development, starting with a gradual

change to the use of hydrogen energy, followed by

a more integrated hydrogen economy and fi nally

what the HyCi doctrine calls a ‘hydrogen civilisation’.

The authors anticipate that this will lead to global

transformation in all aspects of life, society, the

environment and industrial development.

Jurgen Leyrer (Umicore AG & Co, Belgium) outlined

Umicore’s ‘Process Exellence Model’ for the special

glass and chemical industries. Umicore defi nes

process excellence as any achievement related to Pt

components before, during or after use in a customer’s

production process. They claim to offer cost savings,

for example by reductions in pgm inventory and pgm

losses in operation and during refi ning, reduction

of Rh requirements, energy and raw materials and

increase in the service time of pgm components.

Liudmila Morozova (Supermetal) made a

presentation on this Russian fabricator’s pgm product

manufacturing activities. The company has been

active for 50 years, and for the last 25 years it has

been fabricating equipment for the production of

high-quality glass and monocrystals as well as other

pgm products for technical and medical applications.

They use pyrometallurgical processing of scrap with

high pgm content, which allows scrap alloys to be

refi ned without dealloying, substantially accelerating

processing time and reducing costs. They also use

electrophysical fabrication technologies to produce

dispersion strengthened materials (DSMs) based



on Pt and its alloys with Rh. DSMs allow the use of

manufacturing techniques such as rolling, stamping,

drawing and welding, while the heat resistance of

DSMs (as measured by the creep rate and long-term

strength under operational temperatures and stresses)

is tens of times higher than that of traditional Pt-Rh

alloys. Laminar composite materials (LCM) combine

the properties of regular Pt-Rh alloys with the improved

heat resistance and thermal stability of DSMs. In

combination with a new technology for producing

solid stamped bushing base plates, bushings can be

made 20–30% lighter with increased service life. The

company also manufactures thermocouple wire and

catalyst systems and catchment packs for the nitric

acid industry.

Pavel Khorikov (Krasnoyarsk Non-Ferrous Metals

Plant, Russia) reported on the company’s fabrication

of bushings and other glass making manufacturing

units. The current bushing production range is

200–4000 tips. Materials include dispersion stabilised

Pt10Rh DS. They also make combination bushings,

where a bushing body manufactured from Pt20Rh

alloy is welded to a base plate of Pt10Rh DS. In the fi rst

fi ve months of 2012 the total weight of fabricated pgm

products for the glass industry made by the company

was in excess of 160 kg.

Conclusions

A number of pgm topics were covered during

this conference including pgm nanostructures,

superalloys, pgm refi ning, dental materials,

emissions control and fabricated products, as well

as market based information. In 2012 China was

the world’s leading platinum consuming country

(4), and Kunming PM’2012 was a good platform

for rest of the world to understand the most recent

pgm developments in China and elsewhere. The

conference was followed by a visit to Kunming

Institute of Precious Metals and Sino-Platinum Metals

Co, Ltd. The Kunming Institute of Precious Metals

has published the “Precious Metals Blue Book” and

distributed hard copies during the conference. A

total of 63 papers were published in English and the

conference proceedings are available (5).

The next conference in this series will be held in

2014, venue to be decided upon.

References1 G. Ma, J. Li, Y. Li, X. Sun, Q. Cao and Z. Jia, Precious Met.

(Chin.), 2012, 33, (S1), 208

2 J. L. Thomas and G. F. Brem, Metals Recovery Technology Inc, ‘Process for Recovery of Precious Metals’, US Patent 7,935,173; 2011

3 S. Wang, J. Peng, A. Chen and Z. Zhang, Precious Met. (Chin.), 2012, 33, (S1), 33

4 J. Butler, “Platinum 2012 Interim Review”, Johnson Matthey, Royston, UK, 2012

5 Precious Met. (Chin.), 2012, 33, (S1), 1–304

The ReviewersDr Mikhail Piskulov is General Manager of Johnson Matthey Moscow, Russia, where he is involved in market analysis, sales and new business development. Dr Piskulov graduated from Moscow State University of International Relations with a degree in International Business. Before joining Johnson Matthey in 1993, he worked for the USSR Ministry of Foreign Trade. He holds a PhD in Economics, obtained in 2002, on the competitive advantages of foreign direct investment for the receiving country.

Carol Chiu works in Technology Forecasting and Information at Johnson Matthey Technology Centre. She specialises in the provision of technical and commercial information to Johnson Matthey businesses in Asia. Since she joined Johnson Matthey in 2011, she has worked on many different projects involving usage of pgms in the region.

“Precious Metals Blue Book” 《贵金属蓝皮书》

http://dx.doi.org/10.1595/147106713X666561 •Platinum Metals Rev., 2013, 57, (2), 148–150•


BOOKS“Applied Cross-Coupling Reactions”

Edited by Y. Nishihara (Department of Chemistry, Okayama University, Japan), Series: Lecture Notes in Chemistry, Vol. 80, Springer-Verlag, Berlin, Heidelberg, Germany, 2013, 245 pages, ISBN: 978-3-642-32367-6, £90.00, €106.95, US$129.00

Since the discovery of transition

metal-catalysed cross-coupling

reactions in 1972, various synthetic

uses and industrial applications have been developed.

Cross-coupling reactions catalysed by pgms such

as palladium can produce natural products,

pharmaceuticals, liquid crystals and conjugate

polymers for use in electronic devices. The Nobel

Prize in Chemistry 2010 was awarded jointly to

Richard F. Heck, Ei-ichi Negishi and Akira Suzuki “for

palladium-catalyzed cross couplings in organic

synthesis”. In this book, recent trends in synthesis

and catalytic activities of transition metal catalysts,

mainly palladium, for cross-coupling reactions

are presented.

“How to Invent and Protect Your Invention: A Guide to Patents for Scientists and Engineers”

J. P. Kennedy (The University of Akron, USA), W. H. Watkins with E. N. Ball (University of Akron Research Foundation, USA), John Wiley & Sons, Inc, Hoboken, New Jersey, USA, 2012, 248 pages, ISBN: 978-1-1183-6937-1 (Paperback), £40.50, €48.60, US$59.95

This book is based on lecture notes

developed over twenty-fi ve years at

The University of Akron, USA. It provides a clear, jargon-

free and comprehensive overview of the patenting

process tailored specifi cally to the needs of scientists

and engineers, including:

(a) Requirements for a patentable invention;

(b) How to invent;

(c) New laws created by President Obama’s 2011

America Invents Act;

(d) The process of applying for and obtaining a patent

in the USA and in other countries;

(e) Commercialising inventions and the importance

of innovation.

“Inventing Reactions”Edited by L. J. Gooßen (TU Kaiserslautern, FB Chemie - Organische Chemie, Germany), Series: Topics in Organometallic Chemistry, Vol. 44, Springer-Verlag, Berlin, Heidelberg, Germany, 2013, 354 pages, ISBN: 978-3-642-34285-1, £206.50, €245.03, US$309.00

This book analyses the creative

process associated with some recent

inventions of chemical reactions.

Leading academics describe their

creative solutions to longstanding problems in organic

chemistry. Each chapter provides short overviews of

the context and subsequent developments of their

respective transformations. The book includes a chapter

by Professor Keith Fagnou (posthumously) and David

Stuart (University of Ottawa, Canada) on the discovery

and development of a Pd(II)-catalysed oxidative cross-

coupling of two unactivated arenes.

“Modern Tools for the Synthesis of Complex Bioactive Molecules”

Edited by J. Cossy and S. Arseniyadis (Laboratoire de Chimie Organique, ESPCI ParisTech, Paris, France), John Wiley & Sons, Inc, Hoboken, New Jersey, USA, 2012, 596 pages, ISBN: 978-0-470-61618-5, £100.00, €120.00, US$149.95

Focusing on organic, organometallic

and bio-oriented processes, this book

covers the use of the latest synthetic

tools for the synthesis of complex

biologically active compounds. Innovative methods

are described that make it possible to control the

exact connectivity of atoms within a molecule in

order to set precise three-dimensional arrangements.

Many of the transformations rely on palladium,

rhodium, ruthenium or other pgm catalysts. Chapters

of interest include: ‘C--H Functionalization: A New

Strategy for the Synthesis of Biologically Active Natural

Products’, ‘Metal-Catalyzed C--Heteroatom Cross-

Coupling Reactions’ and ‘Metathesis-Based Synthesis

of Complex Bioactives’.

“Sustainable Preparation of Metal Nanoparticles: Methods and Applications”Edited by R. Luque (Departamento de Química Orgánica, Universidad de Córdoba, Spain) and R. S. Varma (National Risk Management Research Laboratory, US Environmental Protection Agency, USA), RSC Green Chemistry No. 19, The

Publications in Brief



Royal Society of Chemistry, Cambridge, UK, 2013, 230 pages, ISBN: 978-1-84973-428-8, £109.99

This book provides the state-of-the-

art as well as current challenges

and advances in the sustainable

preparation of metal nanoparticles

for a variety of applications. For

example, wet chemistry methods

are frequently used for biomedical applications,

while gas phase deposition on solid supports is

commonly employed in the preparation of catalysts

and electrocatalysts. Platinum, palladium, iridium

and ruthenium are featured. Researchers interested

in the green and environmentally safe production of

nanoparticles will fi nd this book useful.

JOURNALSJournal of Environmental Chemical Engineering

Editors: D. Fatta-Kassinos (University of Cyprus, Nicosia, Cyprus), Y. Lee (Gwangju Institute of Science & Technology (GIST), Gwangju, Republic of Korea), T.-T. Lim (Nanyang Technological University, Singapore) and E. C. Lima (Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil); Elsevier; e-ISSN: 2213-3437

The new online-only journal

Journal of Environmental Chemical Engineering

(JECE) from Elsevier focuses on environmental

sustainability in engineering and chemistry. Published

four times per year, JECE will provide a forum for the

publication of original research on the development

of alternative sustainable technologies for water and

wastewater treatment and reuse; treatment, reuse and

disposal of waste; pollution prevention; sustainability

and environmental safety; green chemistry; and

remediation of environmental accidents.

Materials HorizonsEditor: L. Dunn; Royal Society of Chemistry; ISSN: 2051-6347; e-ISSN: 2051-6355

Materials Horizons from the Royal

Society of Chemistry is a new

peer-reviewed journal publishing

primary research on materials

science. Seth Marder (Georgia

Institute of Technology, USA),

chair of the Editorial Board, said “while published by

a chemical society, the journal will seek to serve the

broader materials community by welcoming papers

that cover the gamut of materials research”. It will

include content specifi cally aimed at educating and

engaging younger researchers. Due to launch late in

2013, access will be free until December 2015.

Special Issue: Asymmetric Gold SynthesisChin. J. Chem., 2012, 30, (11), 2601–2725

Asymmetric synthesis, particularly

utilising catalysts, is very

important for providing chiral

compounds in an enantiopure

form. Contributions dealing with

recent progress in homogeneous

asymmetric catalysis are collected

here. This special issue contains 19 selected papers

including: ‘Enantioselective and -Regioselective

Allylic Amination of Morita-Baylis-Hillman Acetates

with Simple Aromatic Amines Catalyzed by Planarly

Chiral Ligand/Palladium Catalyst’, ‘Iridium-Catalyzed

Allylic Alkylations of Sodium Phenyl Selenide’

and ‘Stereoselective Synthesis of Optically Active

Hydrobenzoins via Asymmetric Hydrogenation of

Benzils with Ru(OTf)(TsDPEN)(6-cymene) as the

Pre-catalyst’.

Special Issue: ElectrocatalysisCatal. Today, 2013, 202, 1–210

A number of European universities

(Alicante, Birmingham, Gothenburg,

Leiden, Liverpool and Ulm), one

research institute (Heyrovsky

Ins t i tu te , P rague) and two

companies (Johnson Matthey, UK,

and Permascand, Sweden) were

involved in the EU-funded ‘ELCAT’

network. The aim was to train young researchers

in theoretical and experimental research methods

and to provide theoretical and synthetic tools to

design new electrocatalysts. The collection of papers

in this special issue, many from groups outside the

ELCAT network, refl ects these aims and strategies.

ELCAT: http://www.elcat.org.gu.se/

Special Issue: Fuel Cells 2012 Science & Technology – A Grove Fuel Cell EventEnergy Procedia, 2012, 28, 1–198

The Fuel Cells 2012 Science and Technology

conference took pace in Berlin, Germany, from 11th–

12th April 2012. It included the award of the 2012

Grove Medal to Professor Dr Hubert Gasteiger, Chair



of Technical Electrochemistry

at the Technical University

of Munich, Germany. Both as

industrial and university scientist,

Professor Gasteiger has made

remarkable contributions

to the understanding of fuel

cell related electrochemistry

and to the vitally important

task of translating application requirements

into fundamental parameters. His interests

include electrocatalysts for low-temperature

fuel cells and electrolysers as well as materials

degradation mechanisms. Twenty articles from

this conference are included in this special

issue. Fuel Cells 2012 Science & Technology:

http://www.fuelcelladvances.com/

Special Issue: The World of Catalysis – A Perspective from The Netherlands

ChemCatChem, 2013, 5, (2), 357–618

This ChemCatChem special issue

is an anthology of the topics

addressed over the last fi ve years

of The Netherlands Catalysis and

Chemistry Conference (NCCC). It

refl ects the development of new

or renewed catalysis research

from heterogeneous catalysis, homogeneous catalysis

and biocatalysis. Items of interest include: ‘Pt/Al2O3

Catalyzed 1,3-Propanediol Formation from Glycerol

Using Tungsten Additives’, ‘Stable and Effi cient Pt–Re/

TiO2 Catalysts for Water-Gas-Shift: On the Effect of

Rhenium’, ‘NanoSelect Pd Catalysts: What Causes

the High Selectivity of These Supported Colloidal

Catalysts in Alkyne Semi-Hydrogenation?’ and ‘Effects

of Support, Particle Size, and Process Parameters on

Co3O4 Catalyzed H2O Oxidation Mediated by the

[Ru(bpy)3]2+ Persulfate System’.

ON THE WEB2012 Fuel Cell Patent Review

The “2012 Fuel Cell Patent Review” is the second Fuel

Cell Today report on annual fuel cell patent activity. It

analyses both granted patents and patent applications

published in 2011, by comparison with publications

in 2010. The number of granted fuel cell patents

increased by 51% between 2010 and 2011. Fuel cell

patent applications also continue to grow, with a 58%

increase in 2011 versus 2010. The emergence of Asia as

a dominant patenting force has also been identifi ed,

with the World Intellectual Property Organization

observing double-digit growth in applications from

Japan and China. Fuel Cell Today has tracked the

emergence of China as a named country in the fuel

cell patent literature and this is discussed in the 2012

Patent Review.

Find this at: http://www.fuelcelltoday.com/analysis/

patents/2012/2012-fuel-cell-patent-review

Global Emissions Management

Latest issue: Volume 3, Issue 05 (January 2013)

The latest update of Global Emissions Management

(GEM) from Johnson Matthey Emission Control

Technologies includes:

(a) Advanced Emission Control Concepts for Gasoline

Engines;

(b) Renault Awards for Johnson Matthey;

(c) Johnson Matthey Acquires the Axeon Group.

Find this at: http://www.jm-gem.com/

Platinum Today

Platinum Today has been redesigned. Its new

simplifi ed homepage presents easy access to all of

its most frequently visited areas such as prices, news

and publications. An upgraded price charting system

allows comparison pricing between all the platinum

group metals. The navigation structure has been

improved but still contains all the same elements

as the old site, including the extensive news and

publications archives.

Find this at: http://www.platinum.matthey.com/



CATALYSIS – APPLIED AND PHYSICAL ASPECTSOn the Key Role of Hydroxyl Groups in Platinum-Catalysed Alcohol Oxidation in Aqueous MediumS. Chibani, C. Michel, F. Delbecq, C. Pinel and M. Besson, Catal. Sci. Technol., 2013, 3, (2), 339–350

In the aerobic selective oxidation of alcohols in

aqueous medium in a batch reactor, the addition of

H2O to dioxane solvent (10–50 vol%) substantially

increased the activity of a Pt/C catalyst. Periodic

DFT calculations were performed to compare the

reactivity of alcohols on the bare Pt(111) surface and

in the presence of adsorbed H2O or OH groups. The

calculations were found to indicate that the presence

of adsorbed OH groups promotes catalytic activity by

participating directly in the catalytic pathways and

reducing the activation barrier. Decarbonylation of

acetaldehyde at 373 K is thought to be the cause of

deactivation of the catalyst.

Recyclable Pd-Incorporated Perovskite-Titanate Catalysts Synthesized in Molten Salts for the Liquid-Phase Oxidation of Alcohols with Molecular OxygenI. B. Adilina, T. Hara, N. Ichikuni, N. Kumada and S. Shimazu, Bull. Chem. Soc. Jpn., 2013, 86, (1), 146–152

Pd-incorporated titanate catalysts (Pd/KSTO) were

prepared by the intercalation of Pd(NO3)2 into layered

potassium titanate (KTO), which proceeded via a

cation-exchange reaction in molten salts. Perovskite

phases of Pd/KSTO were obtained at 600ºC and above,

whereas a lepidocrocite-type layered titanate structure,

similar to that of KTO, was retained at 400ºC. The

Pd/KSTO catalysts were then investigated for the

liquid-phase oxidation of alcohols using molecular

O2. The perovskite-type Pd/KSTO catalyst, exhibited

superior activity, giving a high TON of 800 in the

aerobic oxidation of 1-phenylethanol with no loss of

catalytic activity after three runs.

CATALYSIS – INDUSTRIAL PROCESSApplication of Precious Metal Catalysts in Drug SynthesisQ. Meng, Q. Ye, W. Liu and Y. Wang, Precious Met. (Chin.), 2012, 33, (3), 78–82

Supported pgm catalysts (e.g. Pd/Al2O3, Pd/C, Pd-Co/C

and Ru/C) with high activity and high selectivity are

widely used in the pharmaceutical as well as the fi ne

chemicals industry. The application of these catalysts

in drug synthetic reactions including coupling,

hydroformylation, hydrogenolysis, hydrosilylation,

isomerisation and transfer hydrogenation is described.

(Contains 25 references.)

CATALYSIS – REACTIONSAqueous Phase Transfer Hydrogenation of Aryl Ketones Catalysed by Achiral Ruthenium(II) and Rhodium(III) Complexes and Their Papain ConjugatesN. Madern, B. Talbi and M. Salmain, Appl. Organomet. Chem., 2013, 27, (1), 6–12

Ru and Rh complexes having 2,2-dipyridylamine

ligands substituted at the central N atom by an

alkyl chain terminated by a maleimide functional

group were evaluated along with a Rh(III) complex

of unsubstituted 2,2-dipyridylamine as catalysts

in the transfer hydrogenation of aryl ketones in

H2O with formate as hydrogen donor. All of the

complexes except one led to secondary alcohol

products. Site-specifi c anchoring of the N-maleimide

complexes to the single free cysteine residue of

the cysteine endoproteinase papain endowed this

protein with transfer hydrogenase properties towards

2,2,2-trifl uoroacetophenone.

EMISSIONS CONTROLEffect of Barium Sulfate on Sulfur Resistance of Pt/Ce0.4Zr0.6O2 CatalystY. Zheng, Y. Zheng, Y. Xiao, G. Cai and K.-M. Wei, Catal. Commun., 2012, 27, 189–192

BaSO4-doped ceria zirconia (CZ) solid solution

was prepared using a coprecipitation method. The

synthesised samples were used as supports for

preparing Pt catalysts. BaSO4 was evenly distributed

in the irregular mesoporous structure of the CZ.

Furthermore, the addition of BaSO4 to the CZ improved

Abstracts

NO2

N N

NH2

N N

+ [H] Pd/C

Q. Meng et al., Precious Met. (Chin.), 2012, 33, (3), 78–82



the desorption of sulfur species under a reducing

atmosphere, which could decrease the accumulation

of sulfur species in the catalyst. The sulfur poisoning

resistance of the catalyst was thereby improved.

FUEL CELLSPlatinum Catalysts Supported on Nafi on Functionalized Carbon Black for Fuel Cell ApplicationF. Luo, S. Liao and D. Chen, J. Energy Chem., 2013, 22, (1), 87–92

A Pt/Nafi on functionalised C black catalyst was

characterised by IR spectroscopy, TEM and XRD. TEM

showed that the active Pt component was in the form

of NPs and highly dispersed on the carbon black. The

catalyst showed improved activity towards methanol

anodic oxidation and the ORR, resulting from the high

dispersion of the active Pt component. The catalyst

produced an increase in the electrochemically

accessible surface area and ion channels, as well

as easier charge-transfer at the polymer/electrolyte

interface.

Three-Dimensional Tracking and Visualization of Hundreds of Pt−Co Fuel Cell Nanocatalysts during Electrochemical AgingY. Yu, H. L. Xin, R. Hovden, D. Wang, E. D. Rus, J. A. Mundy, D. A. Muller and H. D. Abruña, Nano Lett., 2012, 12, (9), 4417–4423

A 3D tomographic method for tracking the trajectories

and morphological changes of individual Pt-Co

nanocatalyst particles on a fuel cell C support, before

and after electrochemical ageing via potential sweeps,

was developed. The growth in the Pt shell thickness

and observation of coalescence in 3D are proposed

to explain the decrease in electrochemically

active surface area and the loss of activity of

Pt-Co nanocatalysts in PEMFC cathodes. Along with

atomic-scale EELS imaging, the experiment enables

the correlation of catalyst performance degradation

with changes in particle/interparticle morphologies,

particle–support interactions and the near-surface

chemical composition.

SiO2–RuO2: A Stable Electrocatalyst SupportC.-P. Lo and V. Ramani, ACS Appl. Mater. Interfaces, 2012, 4, (11), 6109–6116

High surface area SiO2–RuO2 (SRO) supports

were obtained using a wet chemical method. Pt

NPs were deposited on their surface. The optimal

1:1 mol ratio of SiO2–RuO2 (SRO-1) had a BET

surface area of 305 m2 g–1 and an electrical

conductivity of 24 S cm–1. SRO-1 demonstrated

10-fold higher electrochemical stability than Vulcan

XC-72R C when subjected to an aggressive accelerated

stability test. The mass activity of Pt-doped SRO-1 was

54 mA mgPt–1, whereas its specific activity was

115 μA cmPt–2. The fuel cell performance obtained

with this catalyst was lower, but compared

favourably against commercial Pt/C.

APPARATUS AND TECHNIQUEPreparation of Pd–Pt Co-Loaded TiO2 Thin Films by Sol-Gel Method for Hydrogen Gas SensingS. Yanagida, M. Makino, T. Ogaki and A. Yasumori, J. Electrochem. Soc., 2012, 159, (12), B845–B849

Pd-, Pt- and Pd–Pt-loaded TiO2 thin films were

prepared and their respective capabilities as H2

gas combustion sensors were investigated. H2 gas

sensing was assessed at 300ºC by measuring the

sample resistance under H2 gas (3%–100%) and

air flow conditions. The Pd–Pt step-by-step loaded

sample showed higher sensitivity than either the Pd

or Pt single-loaded sample for H2 concentrations

of less than 30 vol%. STEM revealed its structure:

Pt fine particles deposited selectively on the Pd

particles predeposited on the TiO2 surface.

ELECTROCHEMISTRYA Kinetic Description of Pd Electrodeposition under Mixed Control of Charge Transfer and DiffusionM. Rezaei, S. H. Tabaian and D. F. Haghshenas, J. Electroanal. Chem., 2012, 687, 95–101

The electrodeposition of Pd from an aqueous

solution containing PdCl2 (0.001 M) and H2SO4

(0.5 M) was studied by CV and potentiostatic current-

time transients (CTTs). From the polarisation curves,

regions corresponding to charge transfer control,

mixed control and diffusion control were identifi ed.

In the mixed control region, the CTTs results suggested

processes involving adsorption, the ion transfer

reaction and 3D progressive nucleation with mixed

charge transfer-diffusion controlled growth. The

analysis of CTTs at short times was performed with

the model proposed by Milchev and Zapryanova.

The reduction reaction of Pd(II) Pd(I), as an ion

transfer reaction, occurs before the formation of the

Pd nucleus.



PHOTOCONVERSIONPorous, Platinum Nanoparticle-Adsorbed Carbon Nanotube Yarns for Effi cient Fiber Solar CellsS. Zhang, C. Ji, Z. Bian, P. Yu, L. Zhang, D. Liu, E. Shi, Y. Shang, H. Peng, Q. Cheng, D. Wang, C. Huang and A. Cao, ACS Nano, 2012, 6, (8), 7191–7198

A Pt NP-adsorbed C nanotube yarn was obtained by

solution adsorption and yarn spinning processes, with

uniformly dispersed Pt NPs throughout the porous

nanotube network. TiO2-based dye-sensitised fi bre

solar cells with a Pt--nanotube hybrid yarn as counter

electrode were fabricated. A power conversion

effi ciency of 4.85% under standard illumination

(AM1.5, 100 mW cm–2) was achieved, comparable to

the same type of fi bre cells with a Pt wire electrode

(4.23%).

Photochemistry between a Ruthenium(II) Pyridylimidazole Complex and Benzoquinone: Simple Electron Transfer versus Proton-Coupled Electron TransferR. Hönes, M. Kuss-Petermann and O. S. Wenger, Photochem. Photobiol. Sci., 2013, 12, (2), 254–261

A Ru(II) complex with two 4,4-bis(trifl uoromethyl)-

2,2-bipyridine chelates and a 2-(2-pyridyl)imidazole

ligand was synthesised. The proton-coupled electron

transfer (PCET) between the Ru(II) complex and

1,4-benzoquinone as an electron/proton acceptor

was investigated by spectroscopic means. Excited-

state deactivation was found to occur predominantly

via simple oxidative quenching, but a minor fraction

of the photoexcited complex was thought to have

reacted via PCET.

REFINING AND RECOVERYSelective Recovery of Precious Metals from Acidic Leach Liquor of Circuit Boards of Spent Mobile Phones Using Chemically Modifi ed Persimmon Tannin GelM. Gurung, B. B. Adhikari, H. Kawakita, K. Ohto, K. Inoue and S. Alam, Ind. Eng. Chem. Res., 2012, 51, (37), 11901–11913

A tannin-based adsorbent was prepared by

immobilising bisthiourea on persimmon tannin

extract. The gel exhibited selectivity for precious

metal ions such as Au(III), Pd(II) and Pt(IV) over base

metal ions such as Cu(II), Fe(III), Ni(II) and Zn(II) in

1–5 mol dm–3 HCl. The real time applicability of the gel

for the recovery of precious metals was demonstrated

for the acidic leach liquor of PCBs from spent mobile

phones.

In Situ Platinum Recovery and Color Removal from Organosilicon StreamsH. Bai, Ind. Eng. Chem. Res., 2012, 51, (50), 16457–16466

The recovery of Pt from organosilicon hydrosilylation

streams is a potential source of cost savings. Here in situ

fi xed-bed adsorption technology was demonstrated

to be effective for Pt recovery and product colour

removal. With the in situ Pt recovery process and

using a functionalised silica gel scavenging material,

a Pt recovery >90% was achieved both from silane

distillation heavy wastes (with initial Pt concentration

of ~50 ppm) and from organosilicon products (with

initial Pt concentration of ~5 ppm).



CATALYSIS – APPLIED AND PHYSICAL ASPECTSPalladium-Gold CatalystLyondell Chemical Technology, US Appl. 2012/0,302,784

A Pd-Au catalyst is prepared by the following method:

(a) mixing TiO2, a carboxyalkyl cellulose and a

hydroxyalkyl cellulose to form a dough; (b) extruding

the dough to produce an extrudate; (c) calcining

the extrudate to produce a calcined extrudate; (d)

impregnating the calcined extrudate with Pd and Au

compounds to produce an impregnated extrudate;

and (e) calcining the impregnated extrudate to

produce the Pd-Au catalyst. This catalyst is used in

producing vinyl acetate by oxidising ethylene with

oxygen in the presence of acetic acid.

CATALYSIS – REACTIONSReusable Hydroformylation CatalystUmicore AG & Co KG, World Appl. 2012/163,831

A novel process for producing 4-hydroxybutyraldehyde

is claimed, where an allyl alcohol is reacted in polar

solvents with CO and H2 in the presence of a catalyst

which is formed from a Rh complex and a cyclobutane

ligand e.g. trans-1,2-(1,3-dialkylphenylphosphinomethyl)-

cyclobutanes, 1, where R1 is alkyl, preferably methyl,

ethyl or propyl; R2 is H or an alkoxy group; R3 and R4,

independently of one another, are H, CH2OR1, CH2O-

aralkyl, CH2OH, CH2-[P(3,5-R1,R1-4-R2-phenyl)2], or

CH2O-(CH2-CH2-O)m-H; where m is 1–1000. The

hydroformylation takes place in a membrane reactor

and the catalyst used is separated off from the reaction

mixture, optionally after adding water, by extraction

with hydrophobic solvents and is reused.

R3 CH2-[P(3,5-R1,R1-4-R2-phenyl)2]

CH2-[P(3,5-R1,R1-4-R2-phenyl)2]R4

World Appl. 2012/163,831

1

Catalyst for Alkylation of Aromatic CompoundsStamicarbon BV, European Appl. 2,540,691; 2013

A method for the alkylation of an aromatic

compound involves the aromatic compound making

contact with an alkane of 1–12 C atoms at 200–500ºC,

preferably 320–400ºC, in the presence of a catalyst

composition consisting of a catalytically active metal

selected from Pt, Pd, Rh, Os, Ir, Ru or a combination

and a promoter metal, e.g. Zn, on a zeolite support. The

molar ratio of the promoter metal to the catalytically

active metal is between 0.01 and 5, preferably

between 0.1 and 0.5.

Catalyst for Naphtha ReformingOOO Nauchno-Proizvodstvennaya Firma, Russian Patent 2,471,854; 2013

A catalyst for reforming gasoline fractions comprises

(in wt%): 0.1–1.0 Pt; 0.1–1.0 Cl; 0.5–3.9 zeolite; 1–2

amorphous Al2SiO5; -Al2O3; and optionally 0.1–0.5

Re. Al(OH)3 powder is mixed with zeolite, this mixture

is peptised with 0.5–20% organic acid, e.g. citric acid,

it is then granulated, heat treated at 630–700ºC and

this is followed by the addition of Pt in the form of

an aqueous solution of chloroplatinic acid and

chlorine in the form of HCl. The catalyst is then

dried and annealed.

EMISSIONS CONTROLPlatinum Group Metal CatalystJohnson Matthey Plc, World Appl. 2012/170,421

A catalyst for treating exhaust gas consists of an

aluminosilicate molecular sieve comprising crystals

with a porous network and at least one pgm with the

majority of the selected pgm embedded in the porous

network relative to the pgm disposed on the surface

in a ratio of ~4:1 to ~99:1. The catalyst comprises

~0.01–10 wt% pgm relative to the weight of the

molecular sieve and the crystals have a mean

crystalline size of ~0.01–10 μm. A method for treating

emissions comprises of: (a) contacting a lean burn

exhaust stream containing NOx and NH3 with the

catalyst at ~150ºC–650ºC; and (b) reducing a portion

of NOx to N2 and H2O at ~150ºC–250ºC and oxidising a

portion of NH3 at ~300ºC–650ºC.

Cold Start CatalystJohnson Matthey Plc, US Appl. 2012/0,308,439

A cold start catalyst consists of: (a) a zeolite catalyst

comprising a base metal, a noble metal and a zeolite;

Patents



and (b) a supported pgm catalyst comprising one or

more pgms and one or more inorganic oxide carriers.

The noble metal is selected from Pt, Pd, Rh or a

mixture. The zeolite catalyst and the supported pgm

catalyst are coated onto a fl ow-through substrate in an

exhaust system.

Three-Way Catalyst Microwave DryingX. Weng et al., Chinese Appl. 102,614,942; 2012

A TWC drying technique consists of taking porous

cordierite as the support and coating the surface

of its internal pores with a catalyst slurry which

contains H2O, composite Al2O3, CeO2-ZrO2 oxygen

storage material and Pd or Rh. The catalyst slurry

coated support is then introduced through

microwave devices and dried at 1400–2500 MHz

microwave to have a water content <7%. The

advantages of the microwave drying technique

include rapid heating speed, high production

efficiency, good working environment, reduced

energy consumption and an increase of catalytic

performance of the catalyst.

FUEL CELLSNanostructured Platinum CatalystAtomic Energy and Alternative Energies Commission, World Appl. 2013/017,772

The process for producing a catalyst PtxMy for PEMFC,

where M is a transition metal selected from Ni, Fe, Co

and Cr, involves: (a) deposition of PtxMy nanostructures

on a support by sputtering; (b) annealing the

nanostructures at 600–1200ºC preferably for 1 h; and

(c) depositing a layer of PtxMy onto the surface of the

nanostructures; and (d) then leaching the metal M.

The catalyst is made with Pt3Ni. The support is the

GDL and the thickness is preferably 200 μm.

Microbial Fuel CellGwangju Institute of Science and Technology, US Appl. 2012/0,315,506

A microbial fuel cell system consists of a unit cell

where the anode is formed on the bottom surface and

the cathode is formed on the top surface of a reactor

which accommodates electrochemically active

microorganisms and an ion exchange membrane is

interposed between the two electrodes. The cathode

consists of a carbon electrode treated with Pt, Pd, Os

or Ru. The unit cells are arranged vertically and are

electrically connected to each other in series through

a conductive fi lm to form a module.

Platinum-Rhodium CatalystTokuyama Corp, Japanese Appl. 2013-037,891

A Pt-Rh catalyst for DMFCs consists of a ratio of

0.10–2.00 mol Rh to 1 mol Pt. The catalysts show a high

MeOH oxidation current at a low voltage in an alkaline

environment. Electrodes containing the title catalysts

can be bonded to anion-exchange membranes and

used in MEAs.

METALLURGY AND MATERIALSBlack Fire Retardant Silicone RubberShanghai University of Engineering Science, Chinese Appl. 102,643,552; 2012

A black fi re retardant silicone rubber is prepared

with (in wt%): 50–60 vinyl- or allyl-capped silicone

rubber; 5–10 hydrogen-containing polysiloxane; 0.1–

0.3 soluble Pt catalyst; and 29.7–44.9 fi re retardant

which is a mixture of carbonised residue of waste tyre

pyrolysis and (NH4)2HPO4. The method of preparing

the black fi re retardant silicone rubber involves adding

the carbonisation residue of waste tyre pyrolysis and

(NH4)2HPO4 into the vinyl- or allyl-capped silicone

rubber, stirring, adding the hydrogen-containing

polysiloxane and the Pt catalyst, stirring, ball milling,

vacuum air exhausting and fi nally curing at 20–40ºC.

MEDICAL AND DENTALPalladium Braze Boston Scientifi c Neuromodulation Corp, US Patent 8,329,314; 2012

An implantable microstimulator comprising a component

assembly housing which consists of a ceramic part, a

metal part selected from Ti and Ti alloys and a Pd interface

layer is claimed. The interface layer comprises Pd which

is combined with a portion of one or both of the metal

part or the ceramic part, forming a bond between the

two parts and further comprising an electrode contact. A

second Pd interface layer bonds the electrode contact to

the ceramic part of the component assembly housing.

REFINING AND RECOVERYSeparation of Pure OsmiumThe Curators of the University of Missouri, World Appl. 2013/020,030

A process for separating Os including from an

irradiated Os-191 mixture, involves: (a) the mixture is

put into contact with an aqueous solution of NaClO at

a concentration of ~12% available Cl2 to form a volatile



OsO4 vapour; (b) the OsO4 vapour is bubbled through

a trapping solution which consists of an aqueous

solution of KOH at a concentration of ~25% w/v to

form dissolved K2[OsO4(OH)2]; (c) the dissolved

K2[OsO4(OH)2] is put in contact with an aqueous

solution of NaHS at a concentration of ~10% w/v to

form an OsS2 precipitate; (d) the OsS2 precipitate is

washed by agitating with H2O; (e) the OsS2 precipitate

is separated from the KOH trapping solution by

centrifuging; (f) the OsS2 precipitate is rinsed with

acetone; and (g) the OsS2 precipitate is then dried.

The advantages of this process are the use of simple

reactions and equipment, and a shorter process

time; therefore, limiting the exposure to potentially

hazardous conditions.

SURFACE COATINGSElectroless Plating of IridiumJapan Kanigen Co, Ltd, Japanese Appl. 2012-241,258

A plating solution comprises either or both of Ir3+ and

Ir4+ plus Ti3+. A preferable plating solution consists

of 0.2–60 mmol l–1 Ir ions, 0.01–2 mol l–1 Ti3+ and

has pH 1–6. The solution may also contain 0.001–1

mol l–1 mono- or dicarboxylic acids or their salts as

stabilisers and 0.001–1 mol l–1 N- and P-free oxidation

inhibiting agents of redox potential –0.1–0.8 V vs. SHE,

e.g. ascorbic acid, erythorbic acid, catechol, catechol

disulfonic acid and their salts. High quality Ir coatings

are directly formed on Cu alloys.



FINAL ANALYSIS

NOx Emissions Control for Euro 6

The control of oxides of nitrogen (NOx) emissions to

meet more stringent motor vehicle emission legislation

has been enabled by the development of various

exhaust gas aftertreatment technologies, notably those

that employ platinum group metals (pgms).

Technology DevelopmentsFor gasoline engines the most common aftertreatment

for the control of NOx, as well as the other major

regulated pollutants, carbon monoxide (CO) and

unburnt hydrocarbons (HCs), is the three-way

catalyst (TWC). This technology was developed

in the late 1970s (1). It allows the oxidation of CO

and HC over platinum-palladium or just palladium

during lean (excess oxygen) conditions to form

carbon dioxide and water, while rhodium performs

the reduction of NOx to N2 under rich (oxygen

depleted) conditions. This technology relies on

the engine operating around the stoichiometric

point (air:fuel ratio of 14.7:1) where maximum

simultaneous reduction of NOx and oxidation of

CO and HCs can take place. Emissions standards

for European gasoline vehicles which have been in

force since 2009 (2) specify NOx emissions must not

exceed 0.06 g km–1 (Table I), a limit that is met by

TWC technology.

For diesel engines, which operate under lean

conditions, NOx is harder to deal with. Previous

diesel vehicles used advanced engine technologies

to signifi cantly lower NOx emissions. For example,

exhaust gas recirculation (EGR) is used to recirculate

a proportion of the exhaust gas back into the engine

cylinders to reduce the cylinder temperature during

combustion and thereby reduce formation of NOx.

A disadvantage of this method is that it increases

emissions of particulate matter (PM). Tighter

PM limits have now been enforced across many

jurisdictions and are met by using a pgm-coated

diesel particulate fi lter (also known as a catalysed

soot fi lter (CSF)).

Table I

European Passenger Car NOx and Particulate Emissions Limits for Euro 5 and Euro 6

Stage Date NOx, g km–1 Particulate mass, g km–1

Number of particles, km–1

Compression Ignition (Diesel)

Euro 5a 2009.09a 0.18 0.005d –

Euro 5b 2011.09b 0.18 0.005d 6.0 × 1011

Euro 6 2014.09 0.08 0.005d 6.0 × 1011

Positive Ignition (Gasoline)

Euro 5 2009.09a 0.06 0.005c, d –

Euro 6 2014.09 0.06 0.005c, d 6.0 × 1011 c, e

a 2011.01 for all modelsb 2013.01 for all modelsc Applicable only to vehicles using direct injection enginesd 0.0045 g km–1 using the particulate measurement proceduree 6.0×1012 km–1 within fi rst three years from Euro 6 effective dates



New Legislation Challenges New legislation in force for European heavy-duty

diesel vehicles from 2013, light-duty diesels from

2014 and some non-road diesel engines from 2014

requires a further reduction of NOx emissions.

As shown in Table I, NOx emissions for light-duty

diesel passenger cars reduce from the current Euro

5 limit of 0.18 g km–1 to the Euro 6 limit of 0.08 g km–1

from 2014. PM emissions are already regulated

to the extremely low level of 0.005 g km–1 by the

current Euro 5 legislation. The development of fuel

effi cient lean-burn gasoline engines also presents

new challenges – NOx levels typically generated in

the engine cylinder, whilst lower than conventional

gasoline engines, are nevertheless still well above

the Euro 6 limits and therefore some form of catalytic

aftertreatment is required.

The two leading catalyst technologies used to

remove NOx in a lean-burn engine to meet the above

legislation are lean NOx trap (LNT) or selective

catalytic reduction (SCR). LNT catalysts remove NOx

from a lean exhaust stream by oxidation of NO to NO2

over a platinum catalyst, followed by adsorption of

NO2 onto the catalyst surface and further oxidation

and reaction with metal species incorporated in the

catalyst, for example barium, to form a solid nitrate

phase. Once the catalyst is fi lled with the solid

nitrate phase, the engine is then run rich for a short

period to release the NOx from its adsorbed state.

The released NOx is then converted during the rich

period to N2 over a rhodium catalyst. SCR systems use

a platinum-based diesel oxidation catalyst (DOC)

or a combination of a DOC and a platinum-based

CSF to oxidise a proportion of the NOx into NO2 and

remove HC/CO. A NOx reductant, usually in the form

of aqueous urea, is then injected into the exhaust gas

after the oxidation catalyst and the NO/NO2 mixture

is then selectively reduced over the downstream SCR

catalyst.

The decision whether to use LNT or SCR on a

vehicle involves many factors. SCR requires space

on the vehicle to fi t the urea tank and dosing system,

which is less of a constraint on heavy-duty and larger

light-duty vehicles. Furthermore, the need to run

the engine rich for LNT systems is more technically

demanding for larger engines so LNT systems are

more suited to smaller light-duty vehicles. SCR

systems are impractical for use on gasoline vehicles

as their NOx output is signifi cantly higher than from

diesel, and hence unfeasibly large urea tanks would

be required.

The FutureNOx and other pollutant levels emitted from vehicles

are assessed by use of a standardised driving cycle

for Europe. The current driving cycle which is used

to measure emissions from light-duty vehicles may be

changed in the future to include an even wider range

of driving conditions, for example further extended

low speed driving conditions such as common in

congested city driving or much higher speed driving

conditions than used in the current drive cycle.

For diesel LNTs the future challenge is to maximise

NOx conversion at low speed driving conditions as

well as providing high NOx conversion during high

speed driving. For diesel SCR systems, the future

challenge is also to boost NOx conversion when

the engine is operating at very low speeds. This low

speed challenge may be helped by moving the SCR

closer to the engine where it can benefi t from higher

temperatures, but there are space and system layout

considerations. There is currently a good deal of

research ongoing into diesel powertrain optimisation

for a wide range of driving scenarios.

The proposed enforcement of a particulate number

limit (3) for gasoline engines in Europe also presents

challenges by requiring control of PM to extremely

low levels in addition to keeping emissions of other

pollutants at minimal levels. One possibility is to use a

fi lter coated with similar material to a TWC as part of

the overall aftertreatment system.

For gasoline engines, new on-board diagnostic limits

that come into force at Euro 6 part 2 in 2017 (3) reduce

by 70% the threshold amount of NOx emitted before

the driver is notifi ed of a problem with the catalyst.

Some manufacturers are therefore looking at ways of

further improving the durability of catalysts, including

by increasing the relative loadings of rhodium. Due to

the excellent NOx reduction capability of rhodium, it

may be possible to substitute palladium with small

quantities of rhodium to give a cost- and performance-

optimised system.

ConclusionsThere remains a good deal that can be done on

controlling NOx emissions from vehicles using pgms.

As regulations tighten, cover more vehicle types and are

adopted by more jurisdictions around the world, greater



use of pgm-containing emissions control systems can be

anticipated. Good progress has been made on the control

of NOx from gasoline engines and developments are

being made on lowering NOx emissions from diesels to

meet upcoming emissions limits.

JONATHAN COOPER* and PAUL PHILLIPS**

Johnson Matthey Emission Control Technologies, Orchard Road, Royston, Hertfordshire SG8 5HE, UK

Email: *[email protected]; **[email protected]

References 1 B. Harrison, B. J. Cooper and A. J. J. Wilkins, Platinum

Metals Rev., 1981, 25, (1), 14

2 ‘Regulation (EC) No 715/2007 of the European Parliament and of the Council of 20 June 2007 on type approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information (Text with EEA relevance)’, The

European Parliament and the Council of the European Union, Offi cial Journal of the European Union, L 171/1, 29th June, 2007

3 ‘Commission Regulation (EU) No 459/2012 of 29 May 2012 amending Regulation (EC) No 715/2007 of the European Parliament and of the Council and Commission Regulation (EC) No 692/2008 as regards emissions from light passenger and commercial vehicles (Euro 6) (Text with EEA relevance)’, The European Commission, Offi cial Journal of the European Union, L 142/16, 1st June, 2012

The AuthorsJonathan Cooper is Gasoline Development Manager at Johnson Matthey Emission Control Technologies and has over 13 years’ experience in global gasoline aftertreatment systems research at Johnson Matthey. He holds a degree and DPhil in Chemistry from the University of Oxford, UK.

Paul Phillips is European Diesel Development Director at Johnson Matthey Emission Control Technologies. He has 17 years’ experience at Johnson Matthey aiding the development of emission control systems. Paul has a BSc in Chemistry and a PhD in Organometallic Chemistry from the University of Warwick, UK.

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EDITORIAL TEAM

Jonathan ButlerPublications Manager

Sara ColesAssistant Editor

Ming ChungEditorial Assistant

Keith WhitePrincipal Information Scientist


Platinum Metals Review is Johnson Matthey’s quarterly journal of research on the science and technologyof the platinum group metals and developments in their application in industry

http://www.platinummetalsreview.com/

www.platinummetalsreview.com

Platinum Metals ReviewJohnson Matthey PlcOrchard Road RoystonSG8 5HE UK

%: +44 (0)1763 256 325@: [email protected]

Editorial Team

Jonathan Butler Publications Manager

Sara Coles Assistant Editor

Ming Chung Editorial Assistant

Keith White Principal Information Scientist

vol 57 issue 2 april 2013 - platinum metals review · vol 57 issue 2 april 2013 e-issn 1471-0676 a...

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