Effects of sintering atmosphere on the interaction between doped yttrium chromite anode and yttria stabilized zirconia electrolyte

Abstract

The perovskite chromite-based oxide materials are potential anodes for solid oxide fuel cells (SOFCs). However, the chemical reactivity between chromite-based anodes and yttria-stabilized zirconia (YSZ) electrolyte is one of the important factors that its limits application in SOFCs. Here, we report the effect of sintering atmosphere on the interaction between Ca and Co co-doped YCrO3 (Y0.8Ca0.2Cr0.8Co0.2O3, YCCC) chromite anode and the YSZ electrolyte. The results of SEM, EDX, and XRD analyses show that the reducing atmosphere of 1% H2-Ar gas can efficiently prevent the interfacial reaction between YCCC and YSZ. However, sintering in air results in the formation of CaZrO3 intermediate reaction layer at the YCCC/YSZ interface. The electrochemical impedance measurements also revealed that the polarization and ohmic resistances of cells sintered in reducing atmosphere are much smaller than the ones sintered in air due to inhibited formation of CaZrO3 at the YCCC/YSZ interface. The reduction of Cr4+ concentration and Ca2+ segregation in the YCCC solid solution in reducing atmosphere may have led to the reduced interaction between YCCC and YSZ.