Fabrication of yttria stabilized zirconia thin films on powder-injected anode substrates by electrophoretic deposition technique for solid oxide fuel cell application

The aim of this study was to fabricate yttria stabilized zirconia (YSZ) thin films on the porous anode substrates for solid oxide fuel cell (SOFC) application using environmentally-friendly chemicals and no pre-sintering requirement together with the scalable and cost-effective fabrication techniques. Therefore, 8 mol% YSZ thin films were deposited by electrophoretic deposition (EPD) technique on the porous NiO-YSZ anode substrates prepared by powder injection molding (PIM) method. The effects of EPD conditions on the electrolyte microstructures were investigated, and the half-cell fabrication parameters and co-sintering temperature were subsequently optimized. The dense YSZ thin films at the thicknesses of 2.12 and 2.93 μm with the full coverage of the porous substrates were obtained at the applied voltage of 30 V for 90 and 120 s, respectively, at the co-sintering temperatures of 1250 °C. The open circuit voltages (OCV) of 0.98-1.06 V were achieved at the operating temperature of 800 °C (as compared to theoretical OCV of 1.14 V), which in turn confirm the high-density YSZ films. Although the anode porosity and pore interconnectivity needed to be further improved for higher SOFC power density, the obtained half-cells already showed the potential of the EPD-PIM combined fabrication methods for the future upscale and cost-effective SOFC production.