Study of Pr0.3Sr0.7CoxMn (1-x)O3 (x=0, 0.3, 0.5, 0.7 and 1) as the cathode materials for intermediate temperature SOFC

Abstract

The decrease of polarization resistance in cathode is the key point for operating at intermediate temperature SOFC (solid oxide fuel cell). In this study, the influence of Co substitution in B-site at complex perovskite on the electronic conductivity of PSCM (Pr0.3Sr0.7Co xMn(1-x)) was investigated. The PSCM series exhibits excellent MIEC (mixed ionic electronic conductor) properties. The ASR (area specific resistance) of PSCM3773 was 0.174 Ω·cm2 at 700°C. The activation energy of PSCM3773 was also lower than other compositions of PSCM. The TEC(thermal expansion coefficient) was decreased by addition of Mn. The ASR values were increased gradually during the thermal cycling test of PSCM37773 due to the delamination between electrolyte and cathode materials. The delamination was caused by the difference of TEC.