Influence of A-site Deficiency in BaZr0.8Y0.2O3- on the Performance of La0.6Sr0.4Co0.2Fe0.8O3-δ -BaZr0.8Y0.2O3-δ Composite Cathodes

Ba1-xZr0.8Y0.2O3-δ(x = 0, 0.025, 0.05 and 0.075) powders were successfully prepared via a combustion method. Coupled with La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), LSCF-Ba1-xZr0.8Y0.2O3-δ composite powders were evaluated as potential cathode materials for proton-conducting solid oxide fuel cells (SOFCs). LSCF showed chemical compatibility with Ba1-xZr0.8Y0.2O3-δ powders up to 1000 °C. LSCF-Ba1-xZr0.8Y0.2O3-δ composite cathodes were painted on both sides of sintered BaZr0.8Y0.2O3-δ pellets, used as electrolytes, and fired at 1000 oC to form symmetrical cells. Electrochemical impedance spectroscopy results for symmetrical cells indicated that the A-site deficiency in BaZr0.8Y0.2O3-δ increased the polarization resistance for the composite cathode compared with the deficiency-free sample, and the larger the increase in the A-site deficiency, the larger the polarization resistance.