Synthesis and Characterization of LnBaCo2O5+δ Layered Perovskites as Cathodes for Intermediate-Temperature Solid Oxide Fuel Cells

Abstract

LnBaCo2O5+δ (Ln=Pr, Gd, Sm, Nd) layered perovskites were successfully synthesized by an EDTA-citrate complexing method. Cathode performance of LnBaCo2O5+δwas investigated in the intermediate temperature range of 450oC-750oC on Sm-doped CeO2 (SDC) electrolyte. PrBaCo2O5+δ (PBCO) showed reasonably good performance among all the compounds examined. Addition of SDC phase to form PBCO/SDC composite cathode greatly improve the electrode performance. The lowest polarization resistance of 0.15-0.17 Ωcm2 at 600oC was achieved on PBCO/SDC composites with PBCO content of 60-70wt%. The results demonstrate the potential of layered perovskites as alternative SOFC cathodes for the intermediate temperature operation.