Symmetrical microtubular solid oxide fuel cells (SOFCs) with a catalyst-impregnated yttria-stabilized zirconia (YSZ) scaffold were fabricated via electrophoretic deposition (EPD). While the pH of the prepared slurry decreased with the amount of phosphate ester (PE) as a charging agent, the electrical conductivity increased. Both the YSZ scaffold and electrolyte slurries with 0.5 wt% PE were stable over 36 h. The deposit thickness of the YSZ electrolyte layer increased with the applied voltage and deposition time. Due to the symmetrical scaffold structure, a single cell could be obtained by a one-step co-firing process. Fine Ni and La0.6Sr0.4CoO3-δ (LSC) catalysts for anodes and cathodes, respectively, can be impregnated and distributed uniformly into the porous YSZ scaffold by a glycine-mediated impregnation technique. The maximum power density was 59, 67, and 71 mW/cm2 at 600, 700, and 800 oC, respectively. After the 50th redox cycle, the single cell exhibited no significant performance degradation.

Keywords: Solid oxide fuel cells, Symmetrical micro tubular single cell, Electrophoretic deposition, Scaffold, Impregnation, Redox stability.