Novel high entropy double pervoskite cathode for solid oxide fuel cells

To attain superior electrochemical performance, a new series of high-entropy double perovskites are investigated as cathodes for solid oxide fuel cells. In this study, three PrBa0.5Sr0.5Co1.5Fe0.5O5 double perovskites with different dopings of La, Pr, Sm, Gd, Nd, Y elements in A-site, high-entropy oxides (HEOs) cathodes are successfully prepared by EDTA-citrate combustion method and used as potential cathodes for SOFC at intermediate temperature. Three HEOs cathodes all form single phase double perovskite structure and match chemically well with Gd0.2Ce0.8O2-δ(GDC) electrolyte. Linear thermal expansion coefficient of (La0.2Pr0.2Sm0.2Gd0.2Nd0.2)Ba0.5Sr0.5Co1.5Fe0.5O5(LPSGNBSCF) at 200-1000 oC range is found to be moderate, 18.39×10-6 K-1. Typical anode supported SOFC with LPSGNBSCF cathode exhibits an excellent output performance of 1000 mW·cm-2 with a lower polarization resistance of 0.3 Ω·cm2 at 800 °C. These results might suggest that LPSGNBSCF can be a potential excellent cathode for SOFC.