review of recent research on nanoparticle

Advanced Powder Technology 19 (2008) 443–457www.brill.nl/apt

Review paper

Review of Recent Research on NanoparticleProduction in Thailand

Tawatchai Charinpanitkul a, Kajornsak Faungnawakij b

and Wiwut Tanthapanichakoon b,∗

a Center of Excellence in Particle Technology, Chulalongkorn University, Bangkok 10330, Thailandb National Nanotechnology Center, National Science and Technology Development Agency,

Pathumthani 12120, Thailand

Received 10 April 2008; accepted 2 May 2008

AbstractPowder technology has already extended its scope of interest to nanoparticles with novel properties andfunctionalities. Since the establishment of the National Nanotechnology Center (NANOTEC) in 2003, re-search activities in nanotechnology have shot up remarkably, including the production of nanoparticles viaphysical, chemical and biological methods. This article reviews and introduces recent works on nanoparticleproduction in Thailand, especially NANOTEC and her nation-wide network of Centers of Excellence. Thecategories of nanoparticles of interest extend from metal and zinc oxide nanoparticles to carbon nanoparti-cles and titanate nanostructures. However, thin films and nanofilms lie beyond the scope of this review.© Koninklijke Brill NV, Leiden and Society of Powder Technology, Japan, 2008

KeywordsNanoparticle technology, vapor-phase production, liquid-phase production, solid-phase production, Thai-land, carbon nanotubes

1. Introduction

Nanotechnology is recognized as a revolutionary manufacturing technology of the21st century involving multidisciplinary research issues that rely on the under-standing and control of substances at the nanoscale length of around 1–100 nm.Nanotechnology is not limited to working with matter at the nanoscale, but also en-compasses research and development of materials, devices and systems that exhibitnovel properties and functions due to their nanoscale dimensions or components.Similarly, nanoparticles refer to ultrafine particles whose sizes are in the range of

* To whom correspondence should be addressed. E-mail: [email protected]

© Koninklijke Brill NV, Leiden and Society of Powder Technology, Japan, 2008 DOI:10.1163/156855208X336693

444 T. Charinpanitkul et al. / Advanced Powder Technology 19 (2008) 443–457

1 nm to several hundred nanometers, depending on the materials, fields and applica-tions concerned [1, 2]. They include particles smaller than the so-called submicronparticles and the longest wavelength of visible light of about 400 nm. In some ap-plications, they are limited to particles smaller than 10–20 nm where their physicalproperties would drastically change [1].

Since the establishment of the National Nanotechnology Center (NANOTEC) in2003, research activities in nanotechnology in Thailand have shot up remarkably.As in many countries, nanotechnology has opened new doors to innovations in sci-ence and technology, thereby enabling academic and technological platforms andcapabilities to improve the life quality of the Thais and enhance the competitive-ness of Thai industries in the global arena. NANOTEC has set up a nation-widenetwork of Centers of Excellence (COE) in nanoscience and technology strategi-cally located in eight universities across the nation. In addition, independent andjoint research works with academic institutions and the industrial sector have beenimplemented in various aspects of nanoparticle synthesis, production, processing,handling, applications, utilizations and safety. Meanwhile, powder/particle technol-ogy has gradually become well established in Thailand since the setup of the ThaiPowder Technology Center in 1993 and the Center of Excellence in Particle Tech-nology (CEPT) in Chulalongkorn University in 2002.

This article reviews and introduces the recent works on nanoparticle productionin Thailand with the focus on recent works in NANOTEC, her network of COEsand CEPT. The types of nanoparticles of interest extend from metal and metal oxidenanoparticles to carbon nanoparticles (CNPs) and titanate nanotubules. However, itshould be noted that thin films and nanofilms lie beyond the scope of this review.

2. Nanoparticle Production Technology

Production of nanoparticles requires understanding of the fundamentals of nano-scale chemistry and physics, and know-how to commercialize them. Broadly speak-ing, there are two approaches to nanoparticle production: top-down and bottom-up.The former makes a material decrease its size from large to nanoscale, whereas thelatter produces nanomaterials by starting from the atomic level [2]. In a narrowersense, the production methods can be classified in several ways, e.g. by the type ofgrowth media and the form of products. Based on the phase in which nanoparticleswere formed and regardless of the original phases of the precursors, this reviewgroups the production methods in three categories: production in the vapor phase,liquid phase and solid phase, respectively. Figure 1 illustrates the correspondingsimplified concepts of nanoparticle formation. Table 1 summarizes the character-istics of nanoparticles produced via various methods. Nanoparticle production inthe vapor phase is often carried out at elevated reaction temperatures and undervacuum, e.g. arc discharge in gas [3, 4] or, under atmospheric pressure, e.g. arcdischarge in liquid [5], pyrolysis [6] and chemical vapor deposition [7]. It is worthnoting that athough arc discharge can be performed either in gas or liquid, particle

T. Charinpanitkul et al. / Advanced Powder Technology 19 (2008) 443–457 445

Figure 1. Schematic diagram of simplified concepts of nanoparticle production in gas, liquid and solidphases.

formation proceeds only in the vapor phase. Generally the particle formation mech-anism can be described as follows: (i) vaporization of precursors along with somecatalyst, (ii) nucleation and (iii) growth stage. The flow field pattern of the vapor-

446 T. Charinpanitkul et al. / Advanced Powder Technology 19 (2008) 443–457Ta

ble

1.Characteristicsof

nanoparticlesproduced

viavariousmethods

Productio

nmethod

Characteristicsof

nanoparticles

References

Materials

Morphology

Particlesize

Aspectratio

BETsurface

(nm)

(–)

area

(m2/g)

Arc

discharge

arc-in-liquid

carbon

MWCNTs

10–30

2–100

NR

[19]

multi-shellednanoparticle

20–50

–NR

Pyrolysis

copyrolysis

Fe-encapsulated

MWCNTs

20–40

2500–5000

NR

[23]

carbon

nanocapsule

10–30

–NR

flamepyrolysis

Pd-doped

ZnO

sphere/rod-like/hexagonal

10–20

–63.7–80.1

[24]

Other

gas-phasereactio

noxidation

ZnO

nanosphere

71–96

–NR

[25]

tetrapod

100–400

∼1NR

tetrapod/m

ultip

od130(pod

size)

4NR

[26]

nanowire

60–1

8025

–170

NR

[27]

Au-do

pedZnO

nanowire

60–1

8025

–170

NR

TiO

2nanowire

22–7

045

–133

NR

[28]

Solvotherm

alsolvotherm

alZnO

nanorod

67–110

1.7–5.6

NR

[34]

sonicatio

n-assisted

titanate

nanotubule

∼10

6–176

179–258

[29]

hydrotherm

alPb

TiO

3nanopowder

990–1880

–NR

[30]

hydrotherm

alTiO

2sphere

8–15

–87

–112

[33]

nanorod/nanoparticle

7–12

5–20

(rod)

203

[31]

composite


Tabl

e1.

(Contin

ued.)

Productio

nmethod

Characteristicsof

nanoparticles

References

Materials

Morphology

Particlesize

Aspectratio

BETsurface

(nm)

(–)

area

(m2/g)

Sol–gel

conventio

nal

V-doped

ZnO

nanorod

∼200

5–10

NR

[38]

sphere

∼100

–NR

TiO

2sphere

<1000

–125

[37]

surfactant-assisted

NiO

sphere

15–25

–38

[39]

Pt-loadedTiO

2sphere

1–2(Pt),5–25(TiO

2)

–89

[40]

Other

liquid-phasereactio

nreduction

Au

disordered

(aggregates)

∼30–60

–NR

[42]

Au

sphere/polygonal

∼15–50

–NR

[41]

Ag

sphere

5–

NR

[43]

electrospinning

Ba 0

.6Sr

0.4TiO

3nanofib

er∼1

60–2

00NR

NR

[45]

NaC

o 2O4

nanofib

er∼2

0–20

0NR

NR

[46]

TiO

2nanofib

er∼8

0–10

0NR

NR

[47]

templating

Au

nanowire(step-cone)

∼200

NR

NR

[44]

emulsion

liquidmem

brane

hydroxyapatite

sphere

<20

–58–227

[49]

microem

ulsion

ZnS

nano

rods

200–

750

80NR

[48]

ellip

soid

70–120

∼3–5

NR

sphere

5–10

0–

NR

nanotube

20–40

50–100

NR

NR—

notreported.


ized species and type of catalyst play key roles in the formation mechanism [8–10].Various nanoparticle products could be obtained from these techniques, e.g. single-walled/multi-walled carbon nanotubes (SWCNTs/MWCNTs) and metal/metal ox-ide nanoparticles.

Nanoparticle production in the liquid phase follows a wet chemical route. A num-ber of methods have been proposed for controlling the type, shape and size ofnanoparticles, ranging from the solvothermal method, including the hydrothermalmethod operating at high temperature and pressure, to the sol–gel method, template-based method and micelle/microemulsion method operating at low temperature. Insome cases, combined methods, such as the surfactant-assisted templating sol–gelmethod and hydrothermal microemulsion method, have been employed. Gener-ally, the liquid-phase method is conducted in a batch or semibatch system. Theparticle formation mechanism in liquid phase is similar to that of the gas phase.The nanoparticles can be formed in amorphous and crystalline phases, while theirsize and shape can be controlled by controlling the nucleation and growth rates ofparticles. The products range from metal/metal oxide nanoparticles/nanofibers tosemiconductive compounds.

Production of nanoparticles in the solid phase has recently been developed. Of-ten referred to as the mechanochemical method [11, 12], the most commonly usedmethod generally employs a grinding method and can produce nanoparticles of met-als, metal oxides, complex oxides, etc. [1]. The resultant nanoparticles have uniquecharacteristics such as narrow size distribution and good dispersibility. Since fewresearch works on nanoparticle production by solid–solid reactions, such as grind-ing and vibro-milling, have been carried out in Thailand [13–17], they will not bediscussed in this review.

3. Gas-Phase Production

3.1. Arc Discharge

There are many methods to produce CNPs, e.g. laser ablation, vacuum arc dis-charge, thermal pyrolysis of organic compounds and plasma-enhanced vapor de-position [5, 6, 10, 18]. Meanwhile, novel economical processes for synthesizingCNPs have been developed and the ‘arc in water’ method is one of the promisingtechniques [10]. Arc plasma is generated by gradually reducing the gap betweenthe anode and cathode, which are generally made of graphitic carbon. As the car-bon electrodes are vaporized, molecular carbon clusters are formed, which in turnundergo a self-assembly process to form carbon nanostructures. Simultaneous heatand mass transfer during arc discharge and formation of CNPs are recognized asthe key controlling parameters for CNP synthesis. Sano et al. imposed a convectiveflow onto the arc plasma and discovered an optimal condition in which convectivecooling could provide the highest yield of CNPs [10].

Recently, electrodes made of carbon and its composites as well as alternative car-bon sources, such as liquid hydrocarbons, have been employed to produce carbon


Figure 2. Typical TEM images of nanoparticles produced via arc discharge and pyrolysis methods:(a) MWCNTs and multi-shelled CNPs synthesized by arc discharge in ethanol–water, (b) highly mag-nified image of a MW–CNT tip which reveals a clear graphene layer and (c) CNTs synthesized bypyrolysis at 800◦C with an inset magnified image [19, 23].

nanoparticles and their derivatives. Muthakarn et al. confirmed that arc dischargein alcohols, alkanes and aromatics provided higher CNP yield than the conven-tional arc in water [19]. Figure 2 reveals a typical example of transmission electronmicroscopy (TEM) images of the synthesized CNPs in the case of pure ethanol.The main product was MWCNTs, while some multi-shelled carbon nanoparticleswere also obtained. The magnified image in Fig. 2(b) reveals that the synthesizedMWCNT is made of multi-layers of seamlessly rolled graphene sheets.

3.2. Pyrolysis

Thermal pyrolysis in the absence, or with a trace, of O2 is known to be efficientfor large-scale production of CNPs at low operating costs [6, 20]. The pyrolysis oforganometallic compounds, such as ferrocene and nickel phthalocyanine, was em-ployed for synthesizing CNTs and carbon nanocapsules (CNCs) containing metallicnanoparticles. The encapsulated metallic particles could act as a catalyst for CNPsynthesis. However, using additional hydrocarbon sources, e.g. benzene [21] oracetylene [22], mixed with the organometallic compounds can either provide moreCNPs or reduce the required amount of organometallic compounds.


Charinpanitkul et al. successfully employed copyrolysis of ferrocene–naphtha-lene mixtures in nitrogen to synthesize CNPs [23]. The resultant CNTs and CNCscontained Fe particles in their carbon shells. Figure 2(c) shows examples of TEMimage of the nanoparticle products. It was found that the nanostructure, particlesize distribution and yield of the synthesized products strongly depended on thepyrolysis temperature. The hydrodynamic diameter of the synthesized CNPs wasaround 40–80 nm. Using zinc naphthenate and Pd (II) acetylacetonate dissolved intoluene/acetonitrile as precursors, Liewhiran et al. employed flame spray pyrolysisto produce ZnO doped with 0–5 mol% Pd in a single step [24].

3.3. Other Alternative Approaches

Having high potential for fabrication of short-band semiconductor laser and visiblephotoelectronic devices, ZnO is one of the most promising oxide semiconduc-tors. Charinpanitkul et al. [25, 26] employed the gas-phase reaction to control thesynthesis of ZnO nanospheres, nanotetrapods and nanomultipods. Scanning elec-tron microscopy (SEM) and TEM images of typical ZnO nanoparticles formedeither in a single-heated-zone reactor or in a double-heated-zone reactor equippedwith/without an orifice are shown in Fig. 3. The orifice is employed to enhance

Figure 3. Typical SEM images of ZnO nanoparticles: (a) tetrapods with long-length pods,(b) tetrapods with short-length pods and (c) nanopowders. Insets in (a) show magnified TEM im-ages [25, 26].


the mixing between Zn vapor and air. The synthesized ZnO particles were col-lected on a silicon wafer while being quenched with cooling water in order toenhance deposition flux by thermophoresis and to avoid the growth of the col-lected particles on the substrate. Combining the experimental results with computa-tional fluid dynamics simulations, the formation mechanisms of ZnO nanotetrapodsand nanospheres have been modeled. Meanwhile, Hongsith et al. prepared ZnOnanowires and Au-doped ZnO nanowires via oxidation reaction at 600 for 24 h.An ethanol sensor based on these ZnO nanowires was successfully fabricated byapplying Ag electrodes at each end of the detector tube and inserting a coil heaterinto the tube [27].

Titanium dioxide (TiO2) and TiO2-derived nanoparticles are widely used invarious applications, such as dye-sensitized solar cells, photocatalytic wastewatertreatment, gas sensors, etc. Although TiO2 nanoparticles are commonly producedvia wet chemical routes, e.g. sol–gel, microemulsion and hydrothermal methods,gas-phase methods have been reported, such as the metalloorganic chemical vapordeposition process and thermal evaporation method. However, none of these drymethods could grow the TiO2 nanostructures as a size-controlled process. Daothonget al. reported the size-controlled growth of TiO2 nanowires by oxidation of Tisubstrates in the presence of ethanol vapor at low pressure and high tempera-ture [28].

4. Liquid-Phase Production

4.1. Solvothermal Synthesis

Solvothermal synthesis is one of the most powerful strategies employed for thecrystallization of various unique nanoparticles. A solvothermal reaction is the reac-tion of a hot solution within or on the surface of a substance. When the solvent iswater, it is called hydrothermal synthesis. The reactions proceed in a sealed pres-sure vessel (autoclave) at temperatures above the boiling point of the solvent andinternal autogeneous pressure.

Viriya-empikul et al. discovered a step towards the length control of titanate nan-otubules (TNTs) using hydrothermal reaction with sonication pretreatment [29].Without sonication, the average length of the TNTs synthesized by the hydrother-mal process was as short as around 60 nm due to constricted diffusion of thehydroxyl (OH−) and sodium ions (Na+) through the narrow interparticle space ofthe agglomerated titania precursors, thereby retarding the TNT formation. When thesonication pretreatment was applied, much longer TNTs with an average hydrody-namic size of 490–1760 nm were produced. A mechanism contributing to the lengthcontrol was proposed based on microscopic observations. Rujiwatra et al. showedthat nanoparticles of perovskite lead titanate (PbTiO3) were successfully preparedfrom a stoichiometric proportion at low temperature and short reaction time of only130◦C and 3.5 h, respectively. The employment of ultrasonic treatment prior to hy-drothermal reaction was examined in detail. Ultrasonic waves simultaneously acted


both as a catalyst to lower the hydrothermal reaction temperature to a level suit-able for the single-phase PbTiO3 and as an external influence to provide a highdegree of size homogeneity [30]. Pavasupree et al. synthesized high surface areaTiO2 nanoparticles with mesoporous structures by the hydrothermal method. Vari-ous forms of nanoparticles, i.e. nanopowders, nanosheets, nanorods and nanowires,could successfully be synthesized with different features of particle size, BET sur-face area, pore structure and photocatalytic activity [31, 32]. Supphasrirongjaroenet al. synthesized pure anatase TiO2 nanopowders by the solvothermal method. TheTiO2 spheroidal powder was subjected to rapid quenching in various media such asH2O, air and liquid N2. The quenching process represented a simple novel routefor modifying the surface defects of nano-TiO2 and its photocatalytic activity forethylene decomposition [33]. Tonto et al. showed that ZnO nanorods could be pre-pared by a one-step solvothermal reaction of zinc acetate in various alcohols. Theas-synthesized ZnO was found to be an aggregation of nanorods. The linear relationbetween the boiling point of the solvent and the aspect ratio of the nanorod can beused to select the appropriate solvent for the preparation of ZnO nanorods with thedesired aspect ratio [34].

4.2. Sol–Gel

The sol–gel process is a simple wet chemical route for the synthesis of colloidaldispersions of inorganic and organic–inorganic hybrid materials, particularly ox-ides and oxide-based hybrids in various forms of powders, fibers, thin films andmonoliths [35, 36]. Since the precipitated powder obtained is amorphous in nature,further heat treatment is generally required for crystallization.

Phonthammachai et al. prepared mesoporous nanocrystalline titanium dioxidevia the sol–gel technique using titanium glycolate as precursor in HCl solution atvarious HCl:H2O ratios [37]. The kinetics of formation was thoroughly discussed.The material calcined at 800◦C was found to consist primarily of spherical par-ticles with diameters smaller than 1 μm. The fractal dimension of the critical gelcluster decreased with the acid ratio, whereas the gel strength increased. Appar-ently an increase in the acidity led to a less-dense but somewhat stronger networkstructure. Maensiri et al. reported the optical properties of nanocrystalline powdersof the wurtzite V-doped ZnO synthesized by a simple sol–gel method using metalacetylacetonates of Zn and V, and poly(vinyl alcohol) as precursors [38]. The mor-phology of the powder as revealed by SEM and TEM was affected by the amountof V, causing the formation of either nanorods, nanoparticles or both forms. Thephotoluminescence spectra of all the samples showed four distinct bands: a strongultraviolet emission, a weak blue, a weak blue–green and a weak green, which indi-cated their high structural and optical quality. Sreethawong et al. synthesized a se-ries of metal-based mesoporous oxide nanoparticles under mild conditions througha facile route of modified sol–gel process with surfactant-assisted templating tech-nique. Nanocrystalline mesoporous structures of NiO, Pt-loaded TiO2, In2O3 and


Nd2O3 were successfully synthesized by properly manipulating the hydrolysis andcondensation steps of precursors and solvents, respectively [39, 40].

4.3. Other Alternative Approaches

One of the popular alternative methods is the reduction process [41–43]. Patung-wasa and Hodak controlled the size distribution and, to a minor extent, the shapeof Au nanoparticles prepared by adjusting the pH of the reacting mixture in thecitrate reduction of AuCl4− [42]. The resulting nanoparticles ranged from polyhe-dron types obtained at low pH, elliptical particles at intermediate pH and spheroidsat pH higher than 7.0. The charge of the citrate stabilizing agent modulates theaggregation process after reduction of the AuCl4− ion. Dubas and Pimpan synthe-sized Ag nanoparticles having average size of 5 nm by reduction of silver nitrate inthe presence of humic acids, which acted as capping agents [43]. When exposedto an increasing concentration of sulfurazon-ethyl, the solution with suspendednanoparticles was found to change from yellow to orange red and purple as the her-bicide concentration increased. Recently, Laocharoensuk et al. developed a methodto synthesize step-like porous Au nanowires of different shapes and diameters bysequentially depositing alloy segments with different Au:Ag ratios and dealloyingthe Ag component. For example, step-cone and nano-barbell porous Au nanowireswere generated by a membrane-templated sequential deposition of Au–Ag alloysegments from plating solutions of monotonically decreasing or alternating Au:Agcomposition ratios [44].

Electrospinning was originally developed for making ultrafine polymer fibers.Recently electrospinning has been applied to the synthesis of organic–inorganichybrid fibers. The morphology of the nanofibers depends on the process parameterssuch as applied electric field strength and type of precursor solution. Maensiri et al.focused on the production of metal oxide nanofibers by the electrospinning tech-nique [46, 47]. Nanofibers of sodium cobalt oxide, barium strontium titanate andTiO2 with a diameter range of 20–200 nm were successfully produced.

Charinpanitkul et al. synthesized ZnS nanoparticles with distinguishable mor-phology in quaternary water-in-oil microemulsion systems using various types ofcosurfactants [48]. It could clearly be shown that the size and the morphology ofthe ZnS nanoparticles are dependent upon the types of cosurfactant and the reactantconcentration as well as the molar ratio of water to the surfactant. Employing var-ious synthesis conditions, nanorods, nanotubes, hollow tubes, spherical quantumdots and ellipsoidal nanoparticles could be synthesized. Further investigations onthe accurate control of ZnS size and morphology were conducted with collaborationamong Thai and Indian researchers. Jarudilokkul et al. prepared hydroxyapatites(HAp) nanoparticles by means of an emulsion liquid membrane system (ELM) orwater-in-oil-in-water system [49]. The aim of the work was to evaluate the prepa-ration of HAp nanoparticles using ELM consisting of a mixture of biodegradablesurfactant and an extractant caproic acid. The ELM system yielded nanoparticleswith spherical morphology and narrow particle size range (smaller than 70 nm),


which are significantly different from those prepared by the precipitation method.An increase in the reaction and calcination temperatures resulted in a reduction ofthe specific surface area.

5. Conclusions

This article reviews and introduces recent works on nanoparticle production inThailand, especially NANOTEC and its COE network. The review introduceda number of production methods, such as arc discharge in gas or liquid, py-rolysis and gas-phase oxidation, as well as solvothermal, including hydrother-mal, sol–gel, electrospinning, emulsion/microemulsion and liquid-phase reduction.A variety of nanoparticle products, such as CNTs, Fe-encapsulated CNCs, metal-doped/undoped ZnO and TiO2, and metallic Au and Ag, can be successfully formedas tubes, spheres, rods, tetrapods, multipods, sheets, wires and fibers.

Acknowledgments

Technical support from researchers at NANOTEC is acknowledged. T. C. acknowl-edges financial support from the Centennial fund of Chulalongkorn University tothe CEPT.

References

1. M. Hosokawa, K. Nogi, M. Naito and T. Yokoyama, Nanoparticle Technology Handbook. Else-vier, Amsterdam (2007).

2. G. Cao, Nanostructures and Nanomaterials — Synthesis, Properties, and Applications. ImperialCollege Press, London (2004).

3. S. Iijima, Helical microtubules of graphitic carbon, Nature 354, 56–58 (1991).4. T. W. Ebbesen and P. M. Ajayan, Large-scale synthesis of carbon nanotubes, Nature 358, 220–222

(1992).5. N. Sano, H. Wang, M. Chhowalla, I. Alexandrou and G. A. J. Amaratunga, Nanotechnology:

synthesis of carbon ‘onions’ in water, Nature 414, 506–507 (2001).6. N. Sano, H. Akazawa, T. Kikuchi and T. Kanki, Separated synthesis of iron-included carbon

nanocapsules and nanotubes by pyrolysis of ferrocene in pure hydrogen, Carbon 41, 2159–2179(2003).

7. K. Bartsch and A. Leonhardt, An approach to the structural diversity of aligned grown multi-walled carbon nanotubes on catalyst layer, Carbon 42, 1731–1736 (2004).

8. M. Yudasaka, T. Komatsu, T. Ichihashi and S. Iijima, Single-wall carbon nanotube formation bylaser ablation using double-targets of carbon and metal, Chem. Phys. Lett. 278, 102–106 (1997).

9. X. Wang, Z. Hu, X. Chen and Y. Chen, Preparation of carbon nanotubes and nano-particles bymicrowave plasma-enhanced chemical vapor deposition, Scripta Mater. 44, 1567–1570 (2001).

10. N. Sano, T. Charinpanitkul, T. Kanki and W. Tanthapanichakoon, Controlled synthesis of carbonnanoparticles by arc in water method with forced convective jet, J. Appl. Phys. 96, 645–649 (2004).

11. P. G. McCormick, Application of mechanical alloying to chemical refining, Mater. Trans. JIM 36,161–169 (1995).


12. P. G. McCormick, Mechanical alloying and mechanically induced chemical reactions, in: Hand-book on the Physics and Chemistry of Rare Earths, K. A. Gschneidner Jr and L. Eying(Eds), vol. 24, pp. 47–82. Elsevier Science, Amsterdam, The Netherlands (1997).

13. S. Larpkiattaworn, P. Ngernchuklin, W. Khongwong, N. Pankurddee and S. Wada, The influenceof reaction parameters on the free Si and C contents in the synthesis of nano-sized SiC, Ceram.Inter. 32, 899–904 (2006).

14. J. Chaichanawong, K. Sato, H. Abe, K. Murata, T. Fukui, T. Charinpanitkul, W. Tan-thapanichakoon and M. Naito, Formation of strontium-doped lanthanum manganite(La0.8Sr0.2MnO3) by mechanical milling without media balls, Adv. Powder Technol. 17,613–622 (2006).

15. O. Khamman, W. Chaisan, R. Yimnirun and S. Ananta, Effect of vibro-milling time on phaseformation and particle size of lead zirconate nanopowders, Mater. Lett. 61, 2822–2826 (2007).

16. O. Khamman, R. Wongmaneerung, W. Chaisan, R. Yimnirun and S. Ananta, Preparation of per-ovskite nanopowders by vibro-milling technique, J. Alloy. Compd. 456, 492–497 (2008).

17. O. Khamman, R. Yimnirun and S. Ananta, Effect of calcination conditions on phase formationand particle size of lead nickel niobate powders synthesized by using Ni4Nb2O9 precursor, Mater.Lett. 61, 4466–4470 (2007).

18. N. Sano and M. Nobuzawa, Icicle-like carbon nanotubes forest at tungsten wire tip formed byhigh-voltage corona discharge, Carbon 43, 2224–2226 (2005).

19. P. Muthakarn, N. Sano, T. Charinpanitkul, W. Tanthapanichakoon and T. Kanki, Characteristics ofcarbon nanoparticles synthesized by a submerged arc in alcohols, alkanes and aromatics, J. Phys.Chem. 110, 18299–18306 (2006).

20. C. J. Lee, S. C. Lyu, H. W. Kim, C. Y. Park and C. W. Yang, Large-scale production of alignedcarbon nanotubes by the vapor phase growth method, Chem. Phys. Lett. 359, 109–114 (2002).

21. H. Q. Hou, A. K. Schaper, F. Weller and A. Greiner, Carbon nanotubes and spheres produced bymodified ferrocene pyrolysis, Chem. Mater. 14, 3990–3994 (2002).

22. Y. T. Lee, N. S. Kim, J. Park, J. B. Han, Y. S. Choi, H. Ryu and H. J. Lee, Temperature-dependentgrowth of carbon nanotubes by pyrolysis of ferrocene and acetylene in the range between 700 and1000◦C, Chem. Phys. Lett. 372, 853–859 (2003).

23. T. Charinpanitkul, N. Sano, P. Puengjinda, P. Muthakarn, T. Kanki and W. Tanthapanichakoon,Synthesis of carbon nanoparticles using thermal co-pyrolysis of ferrocene and naphthalene mix-ture, Chiang Mai J. Sci. 32, 379–383 (2005).

24. C. Liewhiran, A. R. Camenzind, A. Teleki, S. E. Pratsinis and S. Phanichphant, Doctor-bladedthick films of flame-made Pd/ZnO nanoparticles for ethanol sensing, Curr. Appl. Phys. 8, 336–339(2008).

25. P. Nartpochananon, T. Fujimoto, T. Charinpanitkul and Y. Otani, Controlled syntheses of ZnOnanoparticles in gas-phase reaction, in: Proc. 5th Asian Aerosol Conf., Kaoshiung, pp. 246–247(2007).

26. T. Satitpitakun, P. Nartpochananon, A. Somwangthanaroj, Y. Otani and T. Charinpanitkul, Ther-mal stability of PMMA film composited with zinc oxide synthesized by gas-phase reaction, in:Proc. Pure and Applied Chemistry Int. Conf., Bangkok, p. 191 (2008).

27. N. Hongsith, C. Viriyaworasakul, P. Mangkorntong, N. Mangkorntong and S. Choopun, Ethanolsensor based on ZnO and Au-doped ZnO nanowires, Ceram. Inter. 34, 823–826 (2008).

28. S. Daothong, N. Songmee, S. Thongtem and P. Singjai, Size-controlled growth of TiO2 nanowiresby oxidation of titanium substrates in the presence of ethanol vapor, Scripta Mater. 57, 567–570(2007).


29. N. Viriya-empikul, N. Sano, T. Charinpanitkul, Y. Kikuchi and W. Tanthapanichakoon, A steptowards length control of titanate nanotubes using hydrothermal reaction with sonication pretreat-ment, Nanotechnology 19, 035601 (2008).

30. A. Rujiwatra, C. Wongtaewan, W. Pinyo and S. Ananta, Sonocatalyzed hydrothermal preparationof lead titanate nanopowders, Mater. Lett. 61, 4522–4524 (2007).

31. S. Pavasupree, S. Ngamsinlapasathian, M. Nakajima, Y. Suzuki and S. Yoshikawa, Syn-thesis, characterization, photocatalytic activity and dye-sensitized solar cell performance ofnanorods/nanoparticles TiO2 with mesoporous structure, J. Photochem. Photobiol. 184, 163–169(2006).

32. S. Pavasupree, S. Ngamsinlapasathian, Y. Suzuki and S. Yoshikawa, Preparation and characteriza-tion of high surface area nanosheet titania with mesoporous structure, Mater. Lett. 61, 2973–2977(2007).

33. P. Supphasrirongjaroen, P. Praserthdam, J. Panpranot, D. Na-Ranong and O. Mekasuwandumrong,Effect of quenching medium on photocatalytic activity of nano-TiO2 prepared by solvothermalmethod, Chem. Eng. J. 138, 622–627 (2008).

34. P. Tonto, O. Mekasuwandumrong, S. Phatanasri, V. Pavarajarn and P. Praserthdam, Preparation ofZnO nanorod by solvothermal reaction of zinc acetate in various alcohols, Ceram. Inter. 34, 57–62(2008).

35. J. E. Moreau, L. Vellutini, M. Wong Chi Man and C. Bied, New hybrid organic–inorganic solidswith helical morphology via H-bond mediated sol–gel hydrolysis of silyl derivatives of chiral(R,R)- or (S,S)-diureidocyclohexane, J. Am. Chem. Soc. 123, 1509–1510 (2001).

36. W. Jin, I. R. Abothu, R. Wang and T. S. Chung, Sol–gel synthesis and characterization ofSrFeCo0.5O3.25−δ powder, Ind. Eng. Chem. Res. 41, 5432–5435 (2002).

37. N. Phonthammachai, T. Chairassameewong, E. Gulari, A. M. Jamieson and S. Wongkasemjit,Structural and rheological aspect of mesoporous nanocrystalline TiO2 synthesized via sol–gelprocess, Microporous Mesoporous Mater. 66, 261–271 (2003).

38. S. Maensiri, C. Masingboon, V. Promarak and S. Seraphin, Synthesis and optical properties ofnanocrystalline V-doped ZnO powders, Opt. Mater. 29, 1700–1705 (2007).

39. T. Sreethawong, S. Chavadej, S. Ngamsinlapasathian and S. Yoshikawa, A modified sol–gelprocess-derived highly nanocrystalline mesoporous NiO with narrow pore size distribution, Col-loid Surf. A 296, 222–229 (2007).

40. T. Sreethawong, T. Puangpetch, S. Chavadej and S. Yoshikawa, Quantifying influence of opera-tional parameters on photocatalytic H2 evolution over Pt-loaded nanocrystalline mesoporous TiO2prepared by single-step sol–gel process with surfactant template, J. Power Sources 165, 861–869(2007).

41. T. Muangnapoh, N. Viriya-empikul, T. Charinpanitkul and N. Sano, Effect of pH on stability ofgold nanoparticles synthesized by aqueous reaction, in: Proc. 14th Regional Symp. on ChemicalEngineering, Yogyakarta, p. 77 (2007).

42. W. Patungwasa and J. H. Hodak, pH tunable morphology of the gold nanoparticles produced bycitrate reduction, Mater. Chem. Phys. 108, 45–54 (2008).

43. S. T. Dubas and V. Pimpan, Humic acid assisted synthesis of silver nanoparticles and its applica-tion to herbicide detection, Mater. Lett. (2008).

44. R. Laocharoensuk, S. Sattayasamitsathit, J. Burdick, P. Kanatharana, P. Thavarungkul andJ. Wang, Shape-tailored porous gold nanowires: from nano barbells to nano step-cones, ACS Nano1, 403–408 (2007).


45. S. Maensiri, W. Nuansing, J. Klinkaewnarong, P. Laokul and J. Khemprasit, Nanofibers of bariumstrontium titanate (BST) by sol–gel processing and electrospinning, J. Colloid Interface Sci. 297,578–583 (2006).

46. S. Maensiri and W. Nuansing, Thermoelectric oxide NaCo2O4 nanofibers fabricated by electro-spinning, Mater. Chem. Phys. 99, 104–108 (2006).

47. W. Nuansing, S. Ninmuang, W. Jarernboon, S. Maensiri and S. Seraphin, Structural characteriza-tion and morphology of electrospun TiO2 nanofibers, Mater. Sci. Eng. B 131, 147–155 (2006).

48. T. Charinpanitkul, A. Chanagul, J. Dutta, U. Rungsardthong andW. Tanthapanichakoon, Effects ofcosurfactant on ZnS nanoparticle synthesis in microemulsion, Sci. Technol. Adv. Mater. 6, 266–271(2005).

49. S. Jarudilokkul, W. Tanthapanichakoon and V. Boonamnuayvittaya, Synthesis of hydroxyapatitenanoparticles using an emulsion liquid membrane system, Colloid Surf. A 296, 149–153 (2007).

review of recent research on nanoparticle

Documents

technology strategi

abstractpowder technology

society of powder technology

advanced powder technology

technology development

center of excellence

research activities

thecategories of nanoparticles