BaZr(0.8)Y(0.2)O(3-delta)-NiO Composite Anodic Powders for Proton-Conducting SOFCs Prepared by a Combustion Method

BaZr0.8Y0.2O3-∂ (BZY)-NiO composite powders with different BZY-NiO weight ratios were prepared by a combustion method as anodes for proton-conducting solid oxide fuel cells (SOFCs). After heating to 1100°C for 6 h, the composite powders were made of a well-dispersed mixture of two phases, BZY and NiO. Chemical stability tests showed that the BZY-NiO anodic powders had good stability against CO2, whereas comparative tests under the same conditions showed degradation for BaCe0.7Zr0.1Y0.2O3-∂NiO, which is at present the most used anode material for proton-conducting SOFCs. Area specific resistance (ASR) measurements for BZY-NiO anodes showed that their electrochemical performance depended on the BZY-NiO weight ratio. The best performance was obtained for the anode containing 50 wt % BZY and 50 wt % NiO, which showed the smallest ASR values in the whole testing temperature range (0.37 Ω cm2 at 600°C). The 50 wt % BZY and 50 wt % NiO anode prepared by combustion also showed superior performance than that of the BZY-NiO anode conventionally made by a mechanical mixing route, as well as that of Pt.