Sm_(0.5)Sr_(0.5)CoO_3 + Sm_(0.2)Ce_(0.8)O_(1.9) composite cathode for cermet supported thin Sm_(0.2)Ce_(0.8)O_(1.9) electrolyte SOFC operating below 600 deg C

摘要

The cathode is a key component in low temperature solid oxide fuel cells. In this study, composite cathode, 75 wt. percent Sm_(0.5)Sr_(0.5)CoO_3 (SSC) + 25 wt. percent Sm_(0.2)Ce_(0.8)O_(1.9) (SDC), was applied on the cermet supported thin SDC electrolyte cell which was fabricated by tape casting, screen-printing, and co-firing. Single cells with the composite cathodes sintered at different temperatures were tested from 400 to 650 deg C. The best cell performance, 0.75 W cm~(-2) peak power operating at 600 deg C, was obtained from the 1050 deg C sintered cathode. The measured thin SDC electrolyte resistance R_s was 0.128 OMEGA cm~2 and total electrode polarization R_p(a + c) was only 0.102 OMEGA cm~2 at 600 deg C.