Effect of cobalt addition on BaCe0.8Gd0.2O2.9 as electrolyte of solid oxide fuel cell

The effect of cobalt oxide addition on the sintering process and electrical performance of BaCe0.8Gd0.2O2.9 (BCGO) ceramics has been evaluated. By adding 1 mol.-% (1CoBCGO) and 2 mol.-% ( 2CoBCGO) of cobalt, the density of 1CoBCGO and 2CoBCGO samples can reach 91 and 94% respectively, after sintering at 1300 degrees C for 10 h, and the open current voltages (OCV) of H-2/air fuel cell with the electrolytes of which were over 0.95 V at different temperatures. Moreover, there were abnormal OCV decreases for the two samples under 700 degrees C. AC impedance and fuel cell testing showed 1CoBCGO sintered at 1300 degrees C had a higher electrical performance than that of 2CoBCGO, and was very similar to that of BCGO sintered at 1500 degrees C.