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The electrophoretic deposition (EPD) technique was employed to fabricate Ketjen black/polyvinylidene fluorid (KB/PVdF) composite films on stainless steel substrates. The preparing procedure of stable suspensions for EPD and its effects on the quality and properties of the composite films were studied. The results revealed that the synthesis of composite particles with a proper KB/PVdF ratio and their homogeneous distribution in the suspensions was a prerequisite to obtain uniform green coatings. The stainless steel substrates coated with KB/PVdF composites exhibited both high electrical conductivity and good corrosion resistance, suggesting the possibility that they serve as the bipolar plates in PEM fuel cells.

We report high-quality and high-density B1 3.25 La 0.75 Ti 3 O 12 ceramics prepared by sintering at a low temperature of 900°C from the nanosized powder with a diameter around 100 nm synthesized by the flash creation method. The densification at 900°C, which was 300°C lower sintering temperature compared with conventional solid-state reaction, enables us to obtain the ceramics showing a remanent polarization of 14.5 μC/cm 2 , a coercive field of 50 kV/cm and a leakage current of ∼10 -9 A/cm 2 . The superior properties are indicated to originate from lower defect concentration achieved by the low temperature sintering.

We report a new sealant material for solid oxide fuel cells (SOFCs) using glass-ceramic. A glass-ceramic based on the CaO-Al2O3-SiO2 system was selected as a sealant because it can be easily molded to give a gastight seal and remains in a solid-like state under typical fuel cell operating conditions. Calcium alumina silicate glass powder is placed in the gas-sealing area before crystallization. During heating, the glass softens and bonds with the SOFC components. At higher temperatures, bulk crystallization occurs in the glass and the viscosity of the glass-ceramic sealant increases. We show that this sealing material which is able to seal at higher viscosities compared with the melt sealing method produces a good gas-tight seal and is chemically stable in contact with SOFC components, e.g., yttria-stabilized zirconia electrolytes and lanthanum chromite separators.

Spray pyrolysis was used to fabricate TiO2-Ag composite powders for application in oxide barrier between filaments of superconducting multifilamentary tapes. The powders were prepared from an aqueous solution of TiO2 sol and AgNO3. SEM and TEM observations revealed that the average size of the synthesized powder was less than 1μm and consisted of well-dispersed fine primary particles of TiO2 and Ag. It was clearly observed that the microstructure of the particles was altered by conditions of heat treatment.