중${\cdot}$저온형 고체 산화물 연료전지의 공기극 물질로 사용되는 $Pr_{0.3}Sr_{0.7}CO_{x}Fe_{(1-x)}O_{3-\delta}$ (x=0, 0.3, 0.5, 0.7, 1) 에 관한 연구

Study of $Pr_{0.3}Sr_{0.7}CO_{x}Fe_{(1-x)}O_{3-\delta}$ (x=0, 0.3, 0.5, 0.7, 1) as the cathode materials for intermediate temperature SOFC

The influence of Co substitution in B-site at perovskite PSCF($Pr_{0.3}Sr_{0.7}CO_{x}Fe_{(1-x)}O_{3}$) was investigated in this study. The PSCF series exhibits excellent MIEC(mixed ionic electronic conductor) properties. ASR(area specific resistance) of PSCF3737 was 0.137 ${\Omega}{\cdot}cm^{2}$ at $700^{\circ}C$. The activation energy of PSCF3737 was also lower than other compositions of PSCF. ASR of PSCF3737 was analysed as two parts at different part of frequency region. Responses at middle frequency part (${\sim}10^2$ Hz) were concerned with oxygen reduction reaction and those at low frequency part (${\sim}10^{-1}$ Hz) were related with oxygen diffusion.