Fabrication and electrochemical properties of SOFC single cells using porous yttria-stabilized zirconia ceramic support layer coated with Ni

A porous yttria-stabilized zirconia (YSZ) ceramic supported single cell with a configuration of porous YSZ support layer coated with Ni/Ni-Ce0.8Sm0.2O1.9 (SDC) anode/YSZ/SDC bi-layer electrolyte/La0.6Sr0.4Co0.2Fe0.8O3−δ cathode was fabricated. The porosity, mechanical strength, and microstructure of porous YSZ ceramics were investigated with respect to the amount of poly(methyl methacrylate) (PMMA) used as a pore former. Porous YSZ ceramics with 56 vol.% PMMA showed a mechanical strength of 24 ± 3 MPa and a porosity of 37 ± 1%. The electrochemical properties of the single cell employing the porous YSZ support layer were measured using hydrogen and methane fuels, respectively. The single cell exhibited maximum power densities of 421 mW/cm2 in hydrogen and 399 mW/cm2 in methane at 800 °C. Moreover, at a current density of 550 mA/cm2, the cell maintained 91% of its initial voltage after operation in methane for 13 h at 700 °C.