Poster Number 1

PREPARATION OF ZSM-5 ZEOLITE MEMBRANES BY COMBINED HYDROTHERMAL SYNTHESIS AND ELECTROPHORETIC DEPOSITION

Hideyuki Negishi, National Institute of Advanced Industrial Science and Technology (AIST), Japan

h-negishi@aist.go.jp Stephanie Reuß, University of Erlangen-Nuremberg, Germany

Wilhelm Schwieger, University of Erlangen-Nuremberg, Germany Aldo R. Boccaccini, University of Erlangen-Nuremberg, Germany

Key Words: ZSM-5 Zeolite, Membrane, Hydrothermal Synthesis, EPD, Gas Separation Zeolites possess uniform and molecular-sized pores. Therefore, zeolite membranes have a great potential for applications in separation and catalysis processes owing to their unique pore structures, adsorption properties and their superior thermal, mechanical and chemical stability compared with polymeric membranes. In this study, preparation of a ZSM-5 zeolite membrane on porous stainless steel disk by hydrothermal synthesis with electrophoretic deposition (EPD) as a seeding method was investigated. Micron size ZSM-5 crystal powder was seeded by EPD on the support disk by using ZSM-5 powder dispersed in ethanol. The seeded amounts were easily controlled by the deposition time during EPD. In comparison with the in situ seeding method, the seeding by EPD requires much shorter time. The membrane after secondary growth had few amounts of zeolite in comparison with the in situ seeding method, but better permeance of single gases such as He, N2 and CO2. Seeding by EPD is thus an attractive method for preparation of gas separation membranes of good performance. Besides, reduction of processing time and production cost is also expected.

Poster Number 2

ELECTROPHORETIC DEPOSITION OF GELATIN/HYDROXYAPATITE COMPOSITE COATINGS ONTO A STAINLESS STEEL SUBSTRATE

Františka Frajkorová, Brno University of Technology, Czech Republic

Esther Molero, Instituto de Ceramica y Vidrio, CSIC, Spain Begoña Ferrari, Instituto de Ceramica y Vidrio, CSIC, Spain

Biodegradable polymers and bioactive ceramics are being combined in a variety of novel materials for

tissue engineering scaffolds. The composites systems combining appropriate mechanical properties of polymers with bioactivity of ceramics seem to be the promising choice for bone tissue engineering. In this work, the incorporating of hydroxyapatite (HA) into a gelatin coating on stainless steel substrate using colloidal processing technology was developed. Titania (Ti) buffer layer prepared by dip coating was inserted to improve the bonding strength between gelatin/HA layer and stainless steel substrate. To obtain the homogeneous Ti layers the dip coating process was optimized in term of the viscosity of Ti suspension and the withdrawal rate. The suspensions composed of 1 vol% of HA and three different additions of gelatin were formulated with a focus on rheological properties for codeposition of both phases by electrophoretic deposition (EPD). The composite coatings performed by EPD were investigated in term of deposition efficiency and kinetics under different electrical conditions. EPD process was performed at ambient and also at the gelling temperature of the suspension. While at the room temperature not electrophoretic growth of the layers was observed, the gelling temperature promotes the growth of the homogeneous, well-adherent coating. The mechanism of electrophoretic co-deposition of gelatin/hydroxyapatite system is discussed. The coatings were characterised by scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The mechanical properties of the coatings were measured. To evaluate in vitro bioactivity of the composites the samples were immersed in simulated body fluid (SBF) at 37°C for 7 and 21 days.

Poster Number 3

DEVELOPMENT AND CHARACTERIZATION OF PEEK/B2O3-DOPED 45S5 BIOACTIVE GLASS COMPOSITE COATINGS OBTAINED BY ELECTROPHORETIC DEPOSITION

Aldo R. Boccaccini, University of Erlangen-Nuremberg, Germany

Enrica Vernè, Politecnico di Torino, Applied Science and Technology Department – DISAT, Italy Marta Miola, Politecnico di Torino, Applied Science and Technology Department – DISAT, Italy

Antonella Piredda, Politecnico di Torino, Applied Science and Technology Department – DISAT, Italy Sigrid Seuss, University of Erlangen-Nuremberg, Germany

45S5 bioactive glass (BG) was doped with B2O3 (3%wt) for its ability to stimulate wound healing and its role in bone physiology, by substituting SiO2, P2O5 and both oxides. The glasses were produced by melting and quenching techniques, milled and sieved to a mean particle size below 20 m. The bioactivity of the glasses was analysed in simulated body fluid (SBF) up to 3 days and all glasses showed the precipitation of hydroxyapatite after one day. Electrophoretic deposition (EPD) was used to prepare composite coatings on planar stainless steel substrates. The suspension for the EPD process contained polyetheretherketone (PEEK), bioactive glass particles, ethanol and citric acid. The parameters of the process (deposition time, particle concentration and composition in suspension and applied voltage) were optimized by a trial-and-error approach. In particular the amounts of PEEK and BG powder were selected after the evaluation of the coating adhesion by a standardized tape test. Moreover the optimal concentration of citric acid was selected on the basis of zeta potential measurements of BG/ethanol solutions with different citric acid amount. Finally a heat treatment was performed to improve the coating adhesion to the substrate. The morphology of the coatings was examined by scanning electron microscopy (SEM). This analysis evidenced the porous and homogeneous structure of the coatings with the glass particles well embedded into the PEEK matrix. The thickness of the coatings varied between 30 and 70 m. Contact angle measurements demonstrated that all coatings are hydrophobic whilst thermogravimetric analysis (TGA) showed that the amount of glass on the coating varied between 59 and 46 wt.%. The bioactivity of the coatings was tested in SBF for up to 14 days. SEM observations and FTIR analyses confirmed that all coatings were highly bioactive. The results thus demonstrated that EPD is a useful technique to deposit homogeneous, microporous and bioactive PEEK-BG composite coatings on metallic substrates for biomedical applications. The novel aspect of this work, which has introduced a boron containing BG as inorganic component of the coating, is highlighted as being highly relevant for the intended applications given the osteogenic effects of the element boron.

Poster Number 4

ELECTROPHORETIC CO-DEPOSITION OF CHITOSAN AND GRAPHENE OXIDE FOR DEVELOPING BIOMEDICAL COATINGS WITH ANTIBACTERIAL EFFECT

Aldo R. Boccaccini, University of Erlangen-Nuremberg, Germany & Imperial College London, United Kingdom

aldo.boccaccini@ww.uni-erlangen.de Anke-Lisa Metze, University of Erlangen-Nuremberg, Germany & Imperial College London, United Kingdom

Fatemehsadat Pishbin, Imperial College London, United Kingdom Mary P. Ryan, Imperial College London, United Kingdom

Mani Diba, Radboud University Nijmegen Medical Center, The Netherlands Milo S. P. Shaffer, Imperial College London, United Kingdom

Keywords: Graphene oxide, chitosan, antibacterial, electrophoretic deposition The aim of this work was to explore the application of EPD to combine chitosan and graphene oxide (GO) in order to obtain strongly antibacterial, yet biocompatible and well-adhered composite coatings for metallic implants. To the author’s knowledge this is the first attempt at applying EPD to simultaneous deposition of these two materials, while EPD of GO and chitosan separately has been reported. In this study, chitosan-GO composite coatings were obtained by cathodic electrophoretic deposition (EPD) on stainless steel substrates. The coatings were characterized by a range of techniques including SEM, FTIR, contact angle (wettability) and surface roughness measurements. In addition antibacterial studies against E.coli were conducted. The coatings were observed to consist of a chitosan matrix with embedded graphene oxide sheets. A decrease in bacteria cell viability of at least 50 % was measured on the chitosan – GO surface in comparison to uncoated stainless steel substrates. The chitosan-GO combination represents a promising new composite with potential for antibacterial applications. It remains to be determined if GO sheets could also lead to damage of mammalian cells which could limit the biomedical application of the present biomaterials.

Poster Number 5

ELECTROPHORETIC DEPOSITION OF METAL NANOPARTICLES ON SEMICONDUCTORS FOR SCHOTTKY-BARRIER HYDROGEN SENSORS

Jan Grym, Institute of Photonics and Electronics, ASCR, Czech Republic

grym@ufe.cz Roman Yatskiv, Institute of Photonics and Electronics, ASCR, Czech Republic

Ondřej Černohorský, Institute of Photonics and Electronics, ASCR, Czech Republic María Verde, Institute of Photonics and Electronics, ASCR, Czech Republic Jan Lorinčík, Institute of Photonics and Electronics, ASCR, Czech Republic

Viet Hung Pham, Center for Functional Nanomaterials, BNL, USA Tesfaye Gebre, Department of Physics, Florida A&M University, USA James H. Dickerson, Center for Functional Nanomaterials, BNL, USA

Key Words: Electrophoretic deposition, metal nanoparticles, Schottky barrier, hydrogen sensors. We report on the electrophoretic deposition (EPD) of metal nanoparticles (NPs) prepared in reverse micelles on semiconductor substrates to fabricate sensitive hydrogen sensors with fast response and high degree of selectivity. The sensors are based on the formation of a Schottky barrier between the metal NPs and the semiconductor substrate. We discuss in detail the mechanism of NP monolayer formation and the parameters which affect the transition from 3D to 2D growth (fig. 1). Deposition of a monolayer is essential for the description of electric charge transport through the metal NP/semiconductor interface and for understanding the phenomena taking place during its exposure to hydrogen. Pt NPs, with the average diameter of 5 nm that were dispersed in an isooctane solution, were prepared by the reverse micelle technique [1]. Constant and pulsed DC voltages were applied for a selected period of time to deposit the NPs on semiconductor substrates. Samples were further contacted by colloidal graphite to measure their electrical characteristics and to investigate their capability of detecting hydrogen [2-4]. Colloidal suspensions were characterized by optical extinction and dynamic light scattering. Structural properties and morphology were evaluated by optical microscopy, scanning electron microscopy, transmission electron microscopy, atomic force microscopy, optical properties by low temperature photoluminescence, and electrical properties by current-voltage and capacitance-voltage measurements. The sensitivity of the graphite/Pt(Pd)/semiconductor structures to hydrogen gas exposure was measured in a through-flow system.

2D+3D growth 2D growth Fig. 1: SEM images of Pt NPs deposited electrophoretically on Si substrates. The work was supported by the international collaboration project M100671201 of the ASCR and EU COST Action TD1105 – project LD14111 of the Ministry of Education CR. Research was carried out in part at the Center for Functional Nanomaterials, Brookhaven National Laboratory, which is supported by the U.S. Department of Energy, Office of Basic Energy Sciences, under Contract No. DE-AC02-98CH10886. 1. D.H. Chen, J. J. Yeh, T.C. Huang, Journal of Colloid and Interface Science 1999, 215, 159-166. 2. R. Yatskiv, J. Grym, K. Zdansky, K. Piksova, Carbon 2012, 50(10), 3928–3933. 3. J. Grym, R. Yatskiv, Semiconductor Science and Technology 2013, 28, 045006-045010. 4. K. Zdansky, J.H. Dickerson, Sensors and Actuators B: Chemical 2013, 184, 295-300.

Poster Number 6

ELECTROPHORETIC VINYL POLYMERS PREPARED VIA ATOM TRANSFER RADICAL POLYMERIZATION AND SMART COATING ON METALS

Tomomi Kameyama, Nagoya Institute of Technology, Japan

kame0422@gmail.com Akinori Takasu, Nagoya Institute of Technology, Japan

Key Words: polyester / polymethacrylate / composite material / zeta potential /

atom transfer radical polymerization (ATRP) Our group had targeted on new synthetic procedure and new polyester design using low temperature polycondensation and click polymerization (polyaddition) of ester-containing new monomers. Recently, we found non-ionic poly(ester-sulfone) prepared via thiol-ene click polymerization and Oxone® oxidation showed anode-selective electrophoresis under the electrophoretic deposition (EPD) condition.1) And we reported selective deposition of a Bioglass®45S5/poly(ester-sulfone)1) and TiO2/poly(ester-sulfone)2) soft film onto a stainless-steel anode by EPD. In this presentation, we investigated an electrophoretic behavior of the vinyl polymer having a sulfonyl group in the side chain and compared with the main chain type of poly(ester-sulfone). Therefore, we synthesized new vinyl polymers containing pendent sulfone to investigate the electrophoretic behavior. At first, we prepared new vinyl monomer having a sulfide group in the side chain [2-(ethylthio)ethyl methacrylate : ETEMA] using methacryloyl chloride by 2-(ethylthio)ethanol. Subsequently, we carried out polymerization of ETEMA. But the monomer was gelled during the polymerization. Consequently, we have tried to copper-catalyzed “atom transfer radical polymerization (ATRP)” of ETEMA. Now the best polymerization condition was follow: Cu1Br, ligand (HMTETA), initiator (Ethyl-2-bromoisobutyrate), solvent (toluene) (Mn=8,300 / Mw/Mn=1.3). To introduce sulfonyl group in the side chain, we tried to Oxone® oxidation of poly(ETEMA) to synthesize electrophoretic vinyl polymers containing sulfonyl group. We demonstrated the anode-selective electrophoretic coating of poly[2-(ethylsulfonyl)ethyl] methacrylate on metals and compared with that of poly(ester-sulfone) (Scheme 1). The vinyl polymers containing sulfonyl group could be anode selectively coated on a stainless-steel from the DMF/1-butanol suspension (Figure 1). The results support our recent new finding that poly(ester-sulfone) show the anode-selective deposition behavior. Coated film using this polymer was transparent, although that using poly(ester-sulfone) was turbid. These fundamental results provide new guideline to fabricate titanium(IV) oxide (TiO2)-based electronic papers as well as self-cleaning materials.

References (1) Nagao, Y.; Takasu, A.; Boccaccini, A. R. Macromolecules, 2012, 45, 3326-3334. (2) Fukuoka, T.; Takasu, A. RSC Advances, accepted

Figure 1 - Anode-selective electrophoretic deposition (EPD) on the stainless steel. Scheme 1 - Polymerization of 2-(ethylthio)

ethyl metacrylate (ETEMA) and Oxidation.

Poster Number 7

ZNO-BASED GAS SENSORS PREPARED BY EPD AND HYDROTHERMAL GROWTH

Roman Yatskiv, Institute of Photonics and Electronics, ASCR, Czech Republic yatskiv@ufe.cz

María Verde, Institute of Photonics and Electronics, ASCR, Czech Republic Jan Grym, Institute of Photonics and Electronics, ASCR, Czech Republic

Key Words: Electrophoretic deposition, ZnO nanoparticles, ZnO nanorods. One dimensional ZnO nanostructures, such as nanorods or nanowires, have recently attracted increasing interest due to their wide range of applications in various fields. ZnO nanorods can be synthesized by a great variety of methods which are generally divided into two main groups: (thermo) physical decomposition/evaporation, i.e., vapor phase methods (such as physical vapor deposition, molecular beam epitaxy, pulsed laser deposition, etc.) and chemical or solution-based methods (e.g., sol-gel, electrodeposition or hydrothermal growth) [1]. Amongst these two kinds, solution-based methods stand out for their simplicity, versatility, cost-effectiveness, good potential for large-scale production and low environmental impact, in contrast to vapor phase methods which require high energy consumptions, sophisticated instrumentation and a high cost [2]. In this context, the obtaining of highly oriented ZnO nanorods (NRs) by hydrothermal growth has been widely reported [2-7]. In many of these works a ZnO seed layer is used to facilitate the heterogeneous growth of the ZnO NRs, as well as to control their morphology, texture and orientation. In this work we report the use of electrophoretic deposition (EPD) of ZnO nanoparticles as seeding method for the preparation of ZnO films, and their subsequent growth into ZnO nanorods under hydrothermal conditions. The use of EPD as seeding procedure allows the obtaining of homogeneous, well oriented ZnO thin films in a simple, low cost, reproducible way. Moreover, the reactivity and small size of the ZnO nanoparticles in the seed layer promotes the growth of narrow ZnO nanorods with a high aspect ratio, which show promising properties for their application in high sensitivity gas sensors or dye sensitized solar cells. The work was supported by EU COST Action TD1105 – project LD14111 of the Ministry of Education CR.

1. H. Morkoc and U. Ozgur, 2009 “Zinc Oxide: Fundamentals, Materials and Device Technology” (Weinheim: Wiley) p. 477.

2. S. Xu, Z. L. Wang, Nano Res. 2011, 4, 1012-1098. 3. C. S. Hsiao, C. H. Peng, S. Y. Chen, S. C. Liou, J. Vac. Sci. Technol. B 2006, 24, 288-291. 4. J. Yang, J. Zheng, H. Zhai et al., J. All. Compd. 2010, 489, 51-55. 5. Y. Lee, Y, Zhang, Serene Lay G.N. et al,. J. Am. Ceram. Soc. 2009, 92, 1940-1945. 6. K. Govender, D. S. Boyle, P. B. Kenway, P. O’Brien, J. Mater. Chem. 14 2575-2591. 7. M. Guo, P. Diao, S. Cai, J. Sol. State Chem., 178, 1864-1873.

Poster Number 8

DESIGN OF ELECTROPHORETIC POLY(2-OXAZOLINE)S FOR HYBRIDIZATION WITH BIOACTIVE GLASS

Terunari Hayashi, Nagoya Institute of Technology, Japan

t.hayashi.acs@gmail.com Akinori Takasu, Nagoya Institute of Technology, Japan

Key Words: perfluoroalkanesulfonylimide / 2-oxazoline / cationic ring-opening polymerization /

bioactive glass / biocompatibility

In our laboratory, bis[(nonafluorobutane)sulfonyl]imide (Nf2NH) was used as a catalyst for the polycondensation1), because of its high activity property. In this presentation, we also tried to use it as a new initiator for cationic ring-opening polymerization of 2-oxazolines. First, we investigated the polymerization activity and the livingness of N-methyl bis[(nonafluorobutane)sulfonyl]imide (Nf2NMe) which was derived from Nf2NH, acting as the new initiator for polymerization of 2-oxazolines. Cationic ring-opening polymerization of 2-ethyl-2-oxazoline proceeded in acetonitrile at 60 oC with Nf2NMe as the initiator and compared it with methyl triflate (TfOMe) as conventional initiator (Scheme 1). As a result, Nf2NMe had the similar polymerization activity to that of TfOMe. In addition, we confirmed the livingness by the two-step polymerization and 1H NMR spectrum.

On the other hand, it is well-known that poly(2-oxazoline)s have biocompatibility, so we next designed electrophoretic poly(2-oxazoline) to survey the application to biological materials conjugated with bioactive glass (Bioglass®45S5), which is silicate material found to bind directly to bone, by electrophoretic deposition (EPD). As we already reported that poly(ester-sulfone) could be deposited on a stainless-steel anode by EPD2), we used the EPD procedure to obtain the poly(2-oxazoline) / bioactive glass composite film. We synthesized poly(2-oxazoline) having pendent sulfone [poly(sulfonyl-oxazoline)] by cationic ring-opening polymerization of sulfide-containing oxazoline and successive Oxone® oxidation (Mn=3.0×103, Mw/Mn=1.3). We found that poly(sulfonyl-oxazoline) showed anode selective deposition under the EPD condition. Subsequently, we tried to conjugate poly(sulfonyl-oxazoline) and bioactive glass by the same EPD procedure to fabricate the poly(sulfonyl-oxazoline) / bioactive glass composite on a stainless-steel anode (Figure 1). Furthermore, after two weeks immersion in SBF (Simulated Body Fluid), we confirmed the appearance of hydroxyapatite on the poly(sulfonyl-oxazoline) / bioactive glass composite by SEM observation. These fundamental results provide new biomaterials for bone regeneration as well as biocompatibility. References 1) T. Moyori, T. Tang, A. Takasu, Biomacromolecules, 2012, 13, 1240-1243. 2) Y. Nagao, A. Takasu, A. R. Boccaccini, Macromolecules, 2012, 45, 3326-3334.

Nf2NMe

CH3CN, 60oC

R = -CH2CH3 (2-ethyl-2-oxazoline)R = -(CH2)4SO2(CH2)2CH3 (sulfonyl-oxazoline)

Scheme 1 - Cationic ring-opening polymerization of 2-oxazolines

Figure 1 – EPD coating of poly(sulfonyl-oxazoline) / bioactive glass Left : cathode, Right : anode

Poster Number 9

ELECTROPHORETIC DEPOSITION OF PRECIPITATED POLYAMIC ACID ON POROUS SUPPORTS

Libor Brabec, J. Heyrovsky Institute of Physical Chemistry of the ASCR, Czech Republic brabec@jh-inst.cas.cz

Petr Sysel, Department of Polymers, Institute of Chemical Technology, Czech Republic Milan Kočiřík, J. Heyrovsky Institute of Physical Chemistry of the ASCR, Czech Republic

Pavel Hrabánek, J. Heyrovsky Institute of Physical Chemistry of the ASCR, Czech Republic

Key Words: precipitation, colloidal polymer, EPD, nanoglobules, mesoporous polyimide Polyamic acid (PAA) is a precursor of polyimide (PI), generally desired for its thermal and dielectric properties. Despite of that there are only several studies on EPD of PAA on a metal anode [1-6] (published in 70’s and 80’s). EPD of PAA on carbon fibers has occurred since 90’s [7-9]. However, all those previous works dealt neither with formation of thin layers nor with porous supports necessary for employing PI layers as membranes. Our experiments result in an easy preparation of thin (micron or submicron) layers of PAA on porous supports. Precipitation of PAA macromolecules leads to negatively charged globules being ideal for subsequent EPD. In contrast to previous works no amine has been added here to form a PAA salt. Composite layers with higher gas-separation efficiency seem to be achievable from binary suspensions containing PAA and small zeolite or silica particles with a comparable zeta potential. PAA can also be modified by a clay [10] and other things. PAA was synthesized from 4,4´-oxydiphthalic anhydride(ODPA) and 4,4´-oxydianiline(ODA) in dimethylsulfoxide (DMSO). Modification of PAA with (3-aminopropyl)triethoxysilane was also performed. PAA dissolved in DMSO precipitated after injection to acetone. Under optimum conditions, PAA size distribution exhibited a maximum at 100-200 nm. The globule size was found to depend not only on the mixing ratio (acetone/DMSO) but also on age of PAA solution, its concentration and PAA chain length. A fine PAA precipitate was also obtainable in water or ethanol (96%). Colloidal PAA was found to have a sufficient zeta potential (-40 mV) for EPD. EPD proceeded on porous discs from stainless-steel or non-conductive alumina (alpha or gamma). During EPD the cloudy liquid became clear so that the deposited PAA amount could be well estimated. After drying, the layers consisted of PAA globules e.g. 50 or 100 nm large, in many cases covered with a continuous PAA film. After heating, PI layers appeared to be compact. PAA/PI coalescence could be due to DMSO residue evaporating from support pores or from polymer globules themselves. So far we achieved a minimum layer thickness of 0.5 µm, obtained from a low-concentrated PAA suspension (less than 0.1 wt.%).

References (authors and years) [1-6] Phillips DC (1972); Alvino WM, Scala LC (1982); Alvino WM, Fuller TJ, Scala LC (1983); Uebner M, Ng KM (1988); Yang C-P, Chen Y-H (1988); Buchwalter SL (1989). [7-9] Iroh JO, Yuan W (1996); Chen Y, Iroh JO (1999); He S, Zhang S, Lu C et al. (2011). [10] Wang C-A, Long B, Lin W et al. (2008)

PAA layers a few microns in thickness deposited on porous Anodiscs (Whatman), in profile. Left image: layer without a continuous PAA film on the surface. Right image: layer of globules covered with a continuous film.

Poster Number 10

MICRO FIBRES CONTAINING LAMINATES PREPARED BY EPD: MICROSTRUCTURE AND FRACTURE BEHAVIOUR

Zdenek Chlup, CEITEC IPM, Institute of Physics of Materials ASCR, Czech Republic

chlup@ipm.cz Hynek Hadraba, CEITEC IPM, Institute of Physics of Materials ASCR, Czech Republic

Daniel Drdlik, CEITEC BUT, Brno University of Technology, Czech Republic Key Words: EPD, mechanical properties, composite, micro-fibres. Electrophoretic deposition is an excellent tool for preparation of sophisticated structures like laminates. Recently, thanks to advances in understanding of kinetics of electrophoretic deposition it was possible to prepare tailored laminates with perfect and strong interface of layers with precise thickness management [1,2]. Mechanical properties of such layered structures can be designed based on numerical predictions [3]. To achieve extraordinary mechanical properties it is used high internal stresses developed during material processing especially CTE mismatch [4].

The ceramic composites containing fibres are usually prepared with the aim that fibres will serve as reinforcement to enhance mechanical properties mainly the fracture resistance of inherently brittle ceramic matrix. In this contribution will be used both alumina and zirconia micro-fibres to help eliminate drying defects in the green body stage before sintering. The co-deposition of ceramic fibres and powder with the targeted final creation of homogenous

crack free ceramic material using EPD is unexplored field from the processing, microstructure and as well properties point of view. The alumina powder reinforced with alumina micro fibres and zirconia powder reinforced by zirconia fibres will be explored in green state and as well after sintering. The influence of fibres in the matrix before and after sintering will described. The complete fibre assimilation in the zirconia matrix was observed contrary in case of alumna matrix some microstructural inhomogeneities were found. The positive influence of micro-fibres on the development of processing defect was also observed. The influence of presence micro-fibre in the microstructure on the basic mechanical properties and comparison with materials prepared without micro-fibres will be demonstrated. Acknowledgement: The authors are grateful for financial support to project GAP108-11-1644 under Czech Science Foundation and Institutional Research Plan no. 68081723. This work was realised in CEITEC – Central European Institute of Technology with research infrastructure supported by the project CZ.1.05/1.1.00/02.0068 financed from European Regional Development Fund. [1] Hadraba, H., Drdlík, D., Chlup, Z., Maca, K., Dlouhý, I., Cihlář, J.: Layered ceramic composites via control of electrophoretic deposition kinetics. J Eur Ceram Soc 33 (2013) 2305-2312. [2] Hadraba H., Drdlik D., Chlup Z., Maca K., Dlouhy I., Cihlar J.: Laminated alumina/zirconia ceramic composites prepared by electrophoretic deposition. J Eur Ceram Soc 32 (2012) 2053–2056. [3] Šestákova L., Bermejo R., Chlup Z., Danzer R.: Strategies for fracture toughness, strength and reliability optimisation of ceramic-ceramic laminates. Int J Mater Res 102 (2011) 613-626. [4]Chlup Z., Hadraba H., Drdlik D., Maca K., Dlouhy I., Bermejo R.: On the determination of the stress-free temperature for alumina–zirconia multilayer structures; Ceram Int 40 (2014) 5787-5793.

Figure 1 – An example of the free surface of zirconia based material prepared via EPD by co-deposition of powder mixed with fibers. Assimilated micro-fibers are

detectable only on the free surfaces. The secondary electron image left and back scattered electron image right.

Poster Number 11

MICRO FIBRES CONTAINING LAMINATES PREPARED BY EPD: KINETICS OF CO-DEPOSITION

Hynek Hadraba, CEITEC IPM, Institute of Physics of Materials ASCR, Czech Republic hadraba@ipm.cz

Zdeněk Chlup, CEITEC IPM, Institute of Physics of Materials ASCR, Czech Republic Daniel Drdlík, CEITEC BUT, Brno University of Technology, Czech Republic

Key Words: alumina, zirconia, micro-fibers, laminates, electrophoretic deposition.

The aim of this work was preparation of alumina and zirconia laminates containing alumina and zirconia micro fibres inside the layers and/or at the inter-layer interface. Electrophoretic deposition was performed from concentrated isopropanolic suspensions stabilized by monochloracetic acid containing mixture of alumina or zirconia powder and certain amount of alumina or zirconia micro fibres. Method for in-situ monitoring of amount of deposited mixture of particles and fibres mass was developed and experimentally checked. Prediction of electrophoretic deposition kinetics was based on the voltage drop measurement and electrophoretic mobility estimation from experimental kinetics data (see Figure 1). Also effect of electrical conditions on particle and fibres arrangement during electrophoretic deposition and final microstructural and mechanical properties of alumina and zirconia layers during electrophoretic deposition was observed. It was found that green and fired densities of deposits depended on electrical conditions during electrophoretic deposition. With decreasing electrical current actual electrophoretic mobility was increased but actual amount of particles taking part in deposition process was decreased. This led to selective deposition of particles

having high electrophoretic mobility and thus having high radiuses. Deposits obtained by electrophoretic deposition under low current and thus under low voltage were formed by larger particles but contained smaller pores. On the other hand layers deposited under high electric current obtained large pores originating from non-ideal arrangement of particles during fast deposition. These microstructural changes reflected in lowering of hardness of deposited ceramics of about 300HV5 after deposition under high voltage. Optimalised process of electrophoretic deposition of alumina and zirconia using isopropanolic suspensions stabilized by monochloracetic acid allowed preparation of laminate consisting of strongly bonded layers containing certain amount of micro fibers. Acknowledgement: The authors are grateful for financial support to project GAP108-11-1644 under Czech Science Foundation and Institutional Research Plan no. 68081723. This work was realized in CEITEC – Central European Institute of Technology with research infrastructure supported by the project CZ.1.05/1.1.00/02.0068 financed from European Regional Development Fund. References: [1] Maca, K., Hadraba, H., Cihlar, J.: Electrophoretic deposition of alumina and zirconia - I. Single-component systems. Ceram Int 30 (2004) 843-852. [2] Hadraba, H., Maca, K., Cihlar, J.: Electrophoretic deposition of alumina and zirconia - II. Two-component systems. Ceram Int 30 (2004) 853-863. [3] Hadraba, H., Drdlík, D., Chlup, Z., Maca, K., Dlouhy, I., Cihlar, J.: Layered ceramic composites via control of electrophoretic deposition kinetics. J Eur Ceram Soc 33 (2013) 2305-2312. [4] Hadraba H., Drdlik D., Chlup Z., Maca K., Dlouhy I., Cihlar J.: Laminated alumina/zirconia ceramic composites prepared by electrophoretic deposition. J Eur Ceram Soc 32 (2012) 2053–2056.

Figure 1 – Prediction of deposited weight (white circles) based on in-situ measurement of

deposited weight during deposition (black circles) and monitoring of electrical conditions during

deposition. White rhombi represent real mass of deposits after drying.

Poster Number 12

DEVICE SCALE ELECTROPHORETIC DEPOSITION OF BAND GAP TUNABLE CdSexS1-x NANORODS

Kevin M Ryan, Materials and Surface Science Institute, University of Limerick, Ireland Pai Liu, Materials and Surface Science Institute, University of Limerick, Ireland

Pai.liu@ul.ie Shalini Singh, Materials and Surface Science Institute, University of Limerick, Ireland Jianjun Wang, Materials and Surface Science Institute, University of Limerick, Ireland

Key Words: Electrophoresis deposition; Nanorods; Assembly; Alignment; Net charge Electrophoretic deposition is an effective and economic route to deposit nanocrystals layer-by-layer..1 In this study, we developed a systematic method to electrophoretically deposit CdSexS1-x alloyed nanorods into a close-packed thin film. This project involved synthesis of phosphonic acid covered CdSexS1-x nanorods2 and the their subsequent organization into a tightly packed assemblies. Because of the net charge and dipole the rods were slowly driven under an applied direct current electrical filed to the electrode. By precisely controlling the concentration, and the deposition conditions, the charged nanorods were accumulated on electrodes with each nanorod vertically aligned and close packed. The highly ordered assembly could be extended over centimeter scale areas with controllable thickness. This result demonstrates EPD is an appropriate process for creation of highly ordered nanorod assemblies at real device scale. This thin film morphology consisting of hierarchical nanocrystal assemblies is an ideal architecture for photonic and photovoltaic devices.

Figure 1. Cross-section SEM showing a multilayer assembly of CdSexS1-x nanorods on Si substrate.

1. Todorov, T. K. et al. Beyond 11% Efficiency: Characteristics of State-of-the-Art Cu 2 ZnSn(S,Se) 4 Solar Cells. Adv. Energy Mater. 3, 34–38 (2013).

2. Singh, S., Singh, A., Palaniappan, K. & Ryan, K. M. Colloidal synthesis of homogeneously alloyed CdSexS1-x nanorods with compositionally tunable photoluminescence. Chem. Commun. (Camb). 49, 10293–5 (2013).

Poster Number 13

ROLL-TO-ROLL MANUFACTURING OF PRISTINE NANOCARBON MATERIALS FOR ENERGY DEVICE APPLICATIONS

Landon Oakes, Vanderbilt University, USA

Landon.oakes@gmail.com William Yates, Vanderbilt University, USA Adam Cohn, Vanderbilt University, USA

Rachel Carter, Vanderbilt University, USA Cary Pint, Vanderbilt University, USA

Key Words: Nanomanufacturing, roll-to-roll, electrophoretic deposition, energy storage, carbon nanomaterial Electrophoretic deposition (EPD) provides a promising tool for large-scale manufacturing of pristine nanocarbon structures using conventional liquid processing techniques. One major roadblock to commercially-viable applications based on nanocarbon materials is the ability to controllably and cost-effectively manufacture macroscopic materials with device-level performance that significantly outperforms current material platforms. Recently, we have demonstrated the ability to deposit a wide array of hybrid nanocarbon structures from polar solvents without the use of surfactants, resulting in clean, functional materials which exhibit enhanced energy storage performance compared with surfactant-processed materials. Here, we demonstrate the ability to utilize this electrophoretic assembly technique as a continuous, roll-to-roll (R2R) material fabrication platform which offers significant advantages for lab-scale design of hybrid functional materials and gives promise to the viability of large-scale processing of nanocarbon materials for low-cost, improved application performance. To emphasize the utility of this approach, we use R2R processing to design hybrid nanostructures employed as binder-free electrodes for lithium-based battery energy storage. Compared to other cost-intensive nanocarbon fabrication techniques, such as chemical vapor deposition, EPD from polar solvents yields materials with equivalent pristine characteristics, but offer enhanced functionality inherit to bottom-up material design.

Poster Number 14

ELECTROPHORETIC CHARACTERIZATION OF CLAY MINERAL SYSTEMS FOR SMECTITE RECOVERY

Jill Manapat, University of the Philippines, Philippines jzmanapat@up.edu.ph

Johanna Michelle Ambait, University of the Philippines, Philippines Ivyleen Bernardo, Mindanao State University-Iligan Institute of Technology, Philippines

Leslie Joy Diaz, University of the Philippines, Philippines Mitch Irene Kate Galvan, University of the Philippines, Philippines

Key Words: zeta potential, electrophoretic deposition, smectite, kaolinite, purification

A study by Bernardo et. al. [1] showed that soil from San Nicolas, Ilocos Norte, Philippines is rich in both smectite and kaolinite. It is therefore possible to add value to this local clay resource if high-purity smectite— a natural clay used for nanocomposite applications— is successfully recovered from it. The usual low-cost technique employed for clay separation is sedimentation. However, the process is time consuming and the resulting purity of the recovered clay is not enough for nanocomposite applications. That being said, this study explored the possibility of using a novel technique that makes use of electrophoretic deposition (EPD) in purifying or upgrading the quality of local clay, specifically for smectite recovery. Moreover, focus was given to understanding the electrophoretic behavior of smectite and kaolinite to effectively control colloidal stability during EPD.

Zeta potential measurements showed that pH has negligible effect on the electrophoretic mobility of

smectite, but has an appreciable effect on the mobility of kaolinite with the isoelectric point (IEP) of kaolinite recorded around pH 5. Knowing this behavior, EPD of a 3.5wt% smectite-kaolinite suspension was carried out at pH 5 and pH 10. Separation of clay minerals was expected only at pH 5 where kaolinite is almost immobile. However, data observed from XRD showed some degree of separation (~60% smectite recovery, Figure 1) for both pH values when EPD was performed using stainless steel 316 electrodes at four volts (4V), for twenty minutes, without stirring, and with an electrode gap of two centimeters (2cm). On-going tests are verifying if an increase in electrode gap will further improve separation due to lesser effect of convective forces that might have driven kaolinite towards the electrode during the motion of smectite. Currently, results show that EPD is indeed a promising technique for upgrading the quality of local clay.

Reference: [1] I. C. Bernardo, J. C. Diamante, and L. J. Lanticse-Diaz, “Characterization of a Philippine Clay,” in AUNSEED-

Met Conference, 2011.

Figure 1 – XRD of EPD deposits showing primary peaks of smectite (S) and kaolinite (K)

Figure 2 – EPD deposits at pH 5 (top) and pH 10 (bottom)

Poster Number 15

OPTIMIZATION OF ELECTROPHORETIC DEPOSITION AND CHARACTERIZATION OF CHITOSAN/45S5 BIOGLASS© COMPOSITE COATINGS ON POROUS TITANIUM FOR BIOMEDICAL APPLICATIONS

Aldo R. Boccaccini, University of Erlangen-Nuremberg, Germany aldo.boccaccini@ww.uni-erlangen.de

Eduardo Gil, University of Seville, Spain Yadir Torres, University of Seville, Spain

Luis Cordero-Arias, University of Erlangen-Nuremberg, Germany Juan Pavón, University of Antioquia, Colombia

José A. Rodríguez-Ortiz, University of Seville, Spain Sara Borjas, University of Seville, Spain

Key Words: Titanium Scaffolds; Stress-shielding; Bioactivity; Biocomposite coating; Bone Implants. Tissues degradation of muscle-skeletal system as consequence of aging, pathologies and traumas, is one of the biggest health issues which strongly affects life quality of worldwide population; in fact, it is considered an important public health problem. Commercially pure titanium (cp Ti) is well known as one of the best in vitro and in vivo bone replacement biomaterial, due to its excellent balance between biomechanical and biofunctional properties. The aim of this work is to test a simultaneous solution to some important limitations of cpTi, which can often compromise the reliability of implants and prosthesis: (i) stress shielding phenomenon (titanium stiffness is higher than bone one) and (ii) a deficient biointerface with bone, which reduces the osteointegration. Porous titanium samples of cp Ti grade IV were obtained by space-holder technique (50%vol of NH4HCO3, 800 MPa, 1250 ºC during 2h in high vacuum), producing a good balance between stiffness and mechanical strength; then, they were coated with Chitosan/45S5 BioGlass© composite by electrophoretic deposition. Homogeneity, infiltration efficiency, and coatings integrity (cracking and adhesion) were evaluated in order to establish correlations with processing parameters (time of deposition, applied voltage, composition, concentration and stability of the colloidal suspension). SEM, XRD, FTIR, and contact profilometry were performed for detailed characterization of the coatings; micro-mechanical properties (micro-hardness and scratch testing) and electrochemical measurements (potentiodynamic polarization and in vitro corrosion tests in SBF) were set-up as well. Global analysis of results allowed us to determine the optimum coating for 25V, 7 min 0.5 g/L Chitosan and 1.5 g/L Bioglass. Acknowledgements: This work was supported by the Spanish Government under Grant No. MAT2011-22981 and the Junta de Andalucía under Grant No. P12-TEP-1401, which were financed in part by the European Regional Development Fund of 2007–2013. The authors want to thank the laboratory technician J. Pinto for its assistance with mechanical testing.

Poster Number 16

ELECTROPHORETIC DEPOSITION OF Mn1.5 Co1.5 O4 ON CROFER22APU FOR APPLICATION IN SOLID OXIDE FUEL CELLS

Cabanas-Polo S., University of Erlangen-Nuremberg, Germany

De Miranda A., Politecnico di Torino, Italy Smeacetto F., Politecnico di Torino, Italy

Salvo M., Politecnico di Torino, Italy Ferraris M., Politecnico di Torino, Italy

Boccaccini A. R., University of Erlangen-Nuremberg, Germany Cr-containing stainless steels have been widely used as metallic interconnects for SOFCs. Volatile Cr-containing species, which originate from the steel, can poison the cathode material in the cells and subsequently cause power degradation in the stack. Mn1.5Co1.5O4 spinel is one of the most promising coating materials due to its high electrical conductivity, good CTE match with the stainless steel substrate and an excellent chromium retention capability. In this work Mn1.5Co1.5O4 spinel coatings were obtained on Crofer22APU substrates by cathodic electrophoretic deposition (EPD) followed by sintering at 800-1000°C in different atmospheres. Highly concentrated suspensions (37.5 g/L) in a mixture of water/ethanol (40/60 vol.%) were prepared and the coatings were obtained by applying 50 V for 20-60 seconds. Dense, homogeneous and crack free Mn1.5Co1.5O4 coatings (with thickness ranging from 10 to 30 µm) were obtained on Crofer22APU substrates. An excellent compatibility was found between Mn1.5Co1.5O4 coated Crofer22APU and a new glass-ceramic sealant, thus suggesting that the spinel protection layer can effectively act as a barrier to outward diffusion of Cr.

Poster Number 17

K0.5Na0.5NbO3 THICK FILMS PREPARED BY ELECTROPHORETIC DEPOSITION

Morgane Dolhen, University of Aveiro, Portugal & University of Limoges, France Amit Mahajan, University of Aveiro, Portugal

Rui Pinho, University of Aveiro, Portugal Elisabete Costa, University of Aveiro, Portugal Gilles Trolliard, University of Limoges, France

Paula M. Vilarinho, University of Aveiro, Portugal Pb(Zr1-xTix)O3 (PZT) based compositions are one the most widely used materials for electromechanical devices, owing to their excellent electrical properties. However, due to lead hazards to environment and human beings, European Union (EU) restricted its use in electrical and electronic equipment [1]. Within this context lead-free piezoelectric have recently become very important from the technical and scientific point of view. Among the several lead free materials, K0.5Na0.5NbO3 (KNN) based might be the possible lead based piezoelectrics; this is due to its high Curie temperature (TC ≈ 420°C), high d33 (80pC/N) and high electromechanical coupling coefficient kp(0.39) [2]. However to make KNN a viable option much more knowledge on KNN family is required. In addition, for some miniaturised applications thick films of KNN are of industrial interest. Among the several techniques to process thick films, electrophoretic deposition (EPD) is gaining interest due to its high flexibility, low cost and simplicity for application [3, 4]. Therefore, in this work, KNN thick films were fabricated by EPD on platinum substrates using KNN powders synthesised by a conventional solid-state reaction. EPD was conducted in acetone with triethanolamine suspensions and films having thickness ranging from 10 to 60 μm with green densities of 2.5g/cm3 were fabricated. Iso-statically pressed KNN films were sintered at 1100°C for 2 h and their morphology and electrical properties analysed. The effects of parameters, such as applied voltage, time of deposition, suspension media and pressing on the individual film were studied. The KNN films depict the relative permittivity and dielectric losses around 500 and 0.07 respectively at room temperature.

Figure 1: Surface morphology of KNN films deposited in acetone with triethanolamine (b) Relative permittivity

(ɛr) and (c) dielectric losses (tanδ) as a function of temperature for KNN thick film (100V-2min) sintered for 2 h at 1100°C and isostically pressed.

1. Directive 2002/95/EC of the European Parliament and of the Council of 27 January 2003 on the restriction of the use of certain hazardous substances in electrical and electronic equipment. EC, 2003.

2. Birol, H., D. Damjanovic, and N. Setter, Preparation and characterization of (K0.5Na0.5)NbO3 ceramics. Journal of the European Ceramic Society, 2006. 26(6): p. 861-866.

3. Boccaccini, A.R. and I. Zhitomirsky, Application of electrophoretic and electrolytic deposition techniques in ceramics processing. Current Opinion in Solid State and Materials Science, 2002. 6(3): p. 251-260.

4. Corni, I., M.P. Ryan, and A.R. Boccaccini, Electrophoretic deposition: From traditional ceramics to nanotechnology. Journal of the European Ceramic Society, 2008. 28(7): p. 1353-1367.

b) a) c)

Poster Number 18

MODIFICATION OF POLYANILINE-BASED GAS SENSOR BY ELECTROPHORETIC DEPOSITION OF METAL NANOPARTICLES IN IONIC LIQUID

Pavol Kunzo, Institute of Electrical Engineering SAS, Slovakia

pavol.kunzo@savba.sk Peter Lobotka, IEE SAS, Slovakia Eva Kováčová, IEE SAS, Slovakia

Key Words: Ionic liquids, Electrophoretic deposition, Conducting polymers, Gas sensor. Room temperature Ionic liquids (ILs) have been recognized as a suitable medium for preparation and stabilization of nanocolloids with long-term stability [1]. Both chemical and physical methods (e.g. vacuum deposition of metals on IL surface) were used to synthesize nanoparticles of various shapes and compositions. Properties of such nanoparticles (especially their catalytic activity) are of great interest for applications in fuel cells, batteries, antibacterial coatings, photocatalysis, and sensors. The current problem is how to deposit the nanoparticles on a proper substrate (battery electrode, sensor surface, etc.) and to get rid of the IL. Colloids of Ni, Ni-Fe or Ag-Cu nanoparticles (12 – 50 nm in size) were produced by magnetron sputtering of the metals onto the surface of imidazolium-based ILs. By this technique very pure nanocolloids can be prepared from almost any material (metals or oxides) processable by vacuum sputtering. Size of the nanoparticles can be tuned by choosing the proper IL composition. EPD was used to decorate surface of chemiresistive gas sensor consisting of a thin film of conducting polymer - polyaniline (~100 nm in thickness) deposited on gold microelectrodes [2]. There are two main issues regarding the application of EPD. First, the surface of the sensor is very sensitive to electrochemical treatment. Both oxidation state and protonation of polyaniline film should be preserved during the EPD to maintain the sensor performance. Second, migration of the ions produces electrostatic boundary layers that shield the charge of the electrodes so that the electric field in the bulk suspension drops effectively to zero. Almost the entire voltage applied across the IL solution is confined into very thin layers next to the electrodes. To overcome these issues we used pulsed EPD. Rectangular pulses of voltage (2 to 4 V in amplitude and 0.5 Hz in frequency) were applied between the polyaniline film and Pt counter electrode in a small EPD cell (~ 1 ml in volume). Nanocolloids based on two ILs (1-Butyl-3-methylimidazolium hexafluorophosphate or 1-Butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) were diluted by methanol to reduce the viscosity of the solution. Both conduction current (which represents charge transfer between the electrode and the electrolyte) and displacement current (which represents charging of electrostatic boundary layer of the electrodes) can be recognized in chronoamperograms recorded during the deposition. Although the both current constituents are important for successful deposition, the former relates to the electrochemical effects at the electrodes and dominates at higher amplitude of pulsed voltage. Voltage amplitude was adjusted to minimize the electrochemical treatment of polyaniline film. Nanoparticles immobilized on the surface of the gas sensor were studied by SEM. After vigorous washing with acetone, nanoparticles remained attached to the surface of polyaniline film. Moreover, as it was confirmed by FTIR spectroscopy, chemical nature of polyaniline (i.e. conducting emeraldine salt) was not affected by the EPD process. Gas sensing properties of the pristine and nanoparticle-decorated polyaniline films were tested by exposure to gaseous ammonia. We found enhanced sensitivity of gas sensor decorated by Ag-Cu nanoparticles. Resistance of the sensor increased in about 650% upon the exposure to 100 ppm of NH3 at room temperature. Selective gas sensing can be implemented using an array of gas sensors treated by different nanoparticles. [1] T. Torimoto, K. Okazaki, T. Kiyama, K. Hirahara, N. Tanaka, and S. Kuwabata, Appl. Phys Lett. 89 (2006) 243117. [2] P. Kunzo, P. Lobotka, M. Micusik, E. Kovacova, Sensors and Actuators B: Chemical. 171-172 (2012) 838–845.

Poster Number 19

ELECTROPHORETIC CO-DEPOSITION OF COPPER AND CARBON ON A HIGH CARBON STEEL SUBSTRATE UNDER NON-ASYMMETRIC AC ELECTRIC FIELDS

Rodríguez Christian, Ingeniería Cerámica, Cinvestav Unidad Saltillo, México

Pech Wilian, Ingeniería Cerámica, Cinvestav Unidad Saltillo, México Rodríguez Francisco Javier, Ingeniería Cerámica, Cinvestav Unidad Saltillo, México & Sustentabilidad de los

Recursos Naturales y Energía, Cinvestav Unidad Saltillo, México González Diego, Ingeniería Cerámica, Cinvestav Unidad Saltillo, México Vargas Gregorio, Ingeniería Cerámica, Cinvestav Unidad Saltillo, México

Key Words: Cathodic, Electrophoretic, Copper, Carbon, Taguchi Copper deposition on materials with both poor electrical conductivity and low corrosion resistance play a crucial role in electrical interconnect technology. In this work, thin films of copper-carbon composites were prepared on high carbon steel substrate by using cathodic electrophoretic deposition (EPD) method under non-asymmetric AC electric field. The experiments were carried out based on the Taguchi experimental design A L16 orthogonal array with four factors of control at 4 levels. Carbon particles were functionalized to ensure its cathodic deposition. The co-deposition of Cu-C composites was achieved using aqueous-ionic liquids mixtures as solvent media. The optimum conditions of deposition process under non-asymmetric ac electric fields were investigated considering parameters such as applied voltage, asymmetric factor, deposition time and water/ionic liquid ratio. The influence of the optimized parameters on porosity and corrosion resistance of the samples was studied by impedance Spectroscopy. The glancing incidence X-ray diffraction confirmed the formation of copper layer on the steel substrates. The morphology of deposited films characterized by scanning electron microscopy has shown deposits with an ordered structure and low porosity than those obtained by dc EPD process.

Poster Number 20

FABRICATION OF SOLID OXIDE FUEL CELLS (SOFCS) ELECTROLYTES BY ELECTROPHORETIC DEPOSITION (EPD) AND OPTIMIZING THE PROCESS

Babak Raissi, Materials and Energy Research Center, Iran

Iman Azarian Borojeni, Materials and Energy Research Center, Iran Amir Maghsoudipour, Materials and Energy Research Center, Iran Mahmood Kazemzad, Materials and Energy Research Center, Iran

Tahereh Talebi, Materials and Energy Research Center, Iran

Fabrication of Solid Oxide Fuel Cells (SOFCs) electrolytes by Electrophoretic Deposition (EPD) was the target of our study. For such purpose, thin layers of Yttria stabilized Zirconia (YSZ) were electrophoretically deposited on pre-sintered NiO-YSZ pellets. A thin graphite film on each pellet was painted to make it conductive and can act as a working electrode for EPD. In this research acetylacetone- ethanol mixture (1:1 by vol.) was selected as the solvent and by applying different electrical fields (25, 50, 75, 100V/cm) in different deposition times (6, 3, 2, 1.5 min respectively) the obtained layers were examined. It was revealed that although electrical field multiplied deposition time remained constant in our experiments, the thickness of the deposited films was increased with increasing the applied electrical field which did not support the Hamaker equation. For the next step, sintering of the deposited layers with 75 V/cm electrical field and 2-minute deposition time was investigated. It was found that although the sintering process was activated at 1250 ºC, 2 hours was not enough to produce a non permeable layer. On the contrary, the layers which sintered at 1400ºC for 2 hours were dense and crack-free. The thickness of such layers was about 7µm and these layers seemed to be suitable for electrolyte of SOFCs.

Poster Number 21

AFFECTABILITY OF CERAMIC NANOPARTICLES OF DIFFERENT COMPOUND FROM SURFACE CHARACTERISTICS IN AC ELECTROPHORETIC DEPOSITION

Mahsa Navidirad, Materials and Energy Research Center, Iran

mnavidirad@yahoo.com Babak Raissi, Materials and Energy Research Center, Iran Reza Riahifar, Materials and Energy Research Center, Iran

Maziar Sahba Yaghmaee, Materials and Energy Research Center, Iran Asghar Kazemzadeh, Materials and Energy Research Center, Iran

Hossein Bahrami, Science and Research Branch of Islamic Azad University, Iran Key words: AC electric field, ceramic nanoparticles, surface characteristic Surface characteristic of particles is one of the main parameters controlling the properties of deposited layer in electrophoretic deposition. To modify the surface characteristic of particles, one of the methods is the addition of additives to the suspensions of powder-solvent. There are many reports dealing with the effect of surface characteristics of particles on uniformity and pattern of deposited layer which most of them are in the case of using DC electric fields for deposition. In this work, affectability of ceramic particles of different compounds from this factor was investigated in the case of using AC electric field. For this purpose, by the help of coplanar electrodes with an inter electrode gap size of 150 µm, nonuniform AC electric field was applied to the suspensions of TiO2-Acetone and WO3-Acetone in the presence and absence of Polyethylenimine (PEI) as an additive. The results proved that while WO3 nanoparticles tend to fill the gap when additive was not used it shows no tendency to fill it in the presence of PEI, however, TiO2 nanoparticles which leave the gap when additive was not applied, fill it in the presence of PEI.

Poster Number 22

DEVELOPMENT OF COMPOSITE ELECTROLYTE FOR THE MICROBATTERY APPLICATION

R. Blanga, Tel Aviv University, Israel K. Freedman, Tel Aviv University, Israel

D. Golodnitsky, Tel Aviv University, Israel golod@post.tau.ac.il

E. Peled, Tel Aviv University, Israel In our mobile society, we heavily rely on portable energy sources leading to driving improvements in battery technology. Although lithium-ion batteries offer the highest energy density among present commercial rechargeable batteries, the technology is still evolving and improving. The improvements are particularly important for the wireless network systems and implantable devices, which need rechargeable microbatteries with dimensions on the scale of 1–10mm3, high energy-density storage and high power capability. 3D concentric on-Si-chip architecture developed by our group, enables the fabrication of 10,000-30,000 microbattery units connected in parallel that minimizes the ion-path length between the electrodes and provides high capacity per footprint area. This is achieved by the insertion of thin films of active battery materials in the high-aspect-ratio microchannels of the perforated chip. Special attention is paid to the membrane, since it must have high ionic conductivity (either by intrinsic ion-conducting pathways or by soaking in the electrolyte) and electrochemical compatibility with anode and cathode materials. In this work, we report on recent achievements in the development of thin-film composite polymer-in-ceramic membranes (electrolytes) for applications in 3D-battery configurations by electrophoretic deposition (EPD) combined with mechanochemistry. We tested electrophoretic co-deposition of several types of composite ceramics and polymers. It was found that with increase in concentration of ceramic powder in the suspension, the deposition of polymer occurs predominantly between the agglomerates of ceramics. The ionic conductivity of the polymer-in-ceramic electrolytes plasticized by 0.3M LiTFSI-PYR14TFSI ionic liquid electrolyte is 0.2-1mS/cm. The membrane follows the complex 3D contours of the electrodes conformally and provides strong mechanical integrity of the microbattery. The experimental data of the study of the effect of magnetic field on the structure of PEO confined in ceramic pores will be presented. Acknowledgments Work is funded by EU FP7, “LABOHR” and -MARS_EV” Projects, and by Israel Academy of Science