A novel composite cathode Er0.4Bi1.6O3-Pr0.5Ba0.5MnO3-delta for ceria-bismuth bilayer electrolyte high performance low temperature solid oxide fuel cells

Abstract

A novel composite cathode consisting of A-site disordered Pr0.5Ba0.5MnO3-δ (PBM) and Er0.4Bi1.6O3 (ESB) is developed for solid oxide fuel cells (SOFCs) with ceria-bismuth bilayer electrolyte. Based on Sm0.075Nd0.075Ce0.85O2-δ|ESB (SNDC|ESB) bilayer structured film, the single cell NiO-SNDC|SNDC|ESB|ESB-PBM achieves an encouraging performance with the maximum power density (MPD) of 994 mW cm-2 and an interfacial polarization resistance (Rp) of 0.027 Ω cm2 at 650 °C. Although a possible reaction between ESB and PBM has been identified in the cathode, the ascendant electrochemical performance including the very high fuel cell performance and Rp obtained here can demonstrate that the novel cobalt-free composite cathode ESB-PBM is a preferable alternative for ceria-bismuth bilayer electrolyte high performance low temperature SOFCs (HPLT-SOFCs) and the interfacial reaction in the cathode seems not to be detrimental to the electrochemical performance.