论文部分内容阅读
Cobalt- free Pr1-xSrxFe0.8Cu0.2O3-δ (x=0.2~0.5),Pr0.5Sr0.5Fe1-yCuyO3-δ (y=0~0.3) were synthesized and systematically characterized towards application as cathode materials for intermediate temperature solid oxide fuel cells(IT-SOFCs).Crystal structure,electrical conductivity and electrochemical performance of these samples as cathode materials for IT-SOFC have been investigated.X-ray diffraction(XRD) indicated that the samples with x≥0.2 were single phase orthorhombic perovskite structure.The thermal expansion coefficient (TEC) increased significantly with increasing Sr addition(0.2≤x≤0.5),decreased lightly with Cu addition(0≤y≤0.05).The electrical conductivity decreased gradually with increasing Sr addition(0.2≤x≤0.5),but decreased with Cu initial addition(y≤0.05).The addition of Sr cations into A site significantly lower the area specific resistance(ASR) of Pr1-xSrxFe0.8Cu0.2O3-δ (x=0.2~0.5) cathode materials.The ASR of Pr0.5Sr0.5Fe1-yCuyO3-δ (y=0.0~0.3) decreased lightly with Cu content and the lowest ASR (0.05 Ω·cm2 @700 oC) was achieved by Pr0.5Sr0.5Fe0.8Cu0.2O3-δ (PSFC5582).This study investigated the influences of A site cations (Pr3+,Sr2+) and B site cations (Fe3+/Fe4+,Cu1+/Cu2+) on the electrochemical properties.The results indicate that the A site cations size and content has more notable influence than that of B site cations.The PSFC5582 oxides show a superior electrocatalytic activity comparable to many previously reported cobalt-based cathodes.It thus promises as a new cathode candidate for IT-SOFC.