Effect of cobalt addition on BaCe_(0.8)Gd_(0.2)O_(2.9) as electrolyte of solid oxide fuel cell

摘要

The effect of cobalt oxide addition on the sintering process and electrical performance of BaCe_(0.8)Gd_(0.2)O_(2.9) (BCGO) ceramics has been evaluated. By adding 1 mol. percent (ICoBCGO) and 2 mol. percent (2CoBCGO) of cobalt, the density of ICoBCGO and 2CoBCGO samples can reach 91 and 94 percent respectively, after sintering at 1300 deg C for 10 h, and the open current voltages (OCV) of H_2/air fuel ceil 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 deg C. AC impedance and fuel cell testing showed ICoBCGO sintered at 1300 deg C had a higher electrical performance than that of 2CoBCGO, and was very similar to that of BCGO sintered at 1500 deg C.