Development of a PrBaMn2O5+delta-La0.8Sr0.2Ga0.85Mg0.15O3-delta composite electrode by scaffold infiltration for reversible solid oxide fuel cell applications

Abstract

In this study, a PrBaMn2O5+delta (PBMO)-La0.8Sr0.2Ga0.85Mg0.15O3-delta (LSGM) composite catalyst was developed for use in a reversible solid oxide fuel cell (SOFC) electrode. Through a chemical compatibility test, a heat treatment temperature at which secondary phases did not form between LSGM and PBMO was determined, and a PBMO-LSGM composite electrode material was synthesized by a scaffold infiltration technique capable of synthesizing a catalyst within the appropriate temperature range. A half-cell test consisting of two identical PBMO-LSGM composite electrodes supported on LSGM pellets found that the optimum infiltration amount of PBMO with respect to the LSGM scaffold was approximately 20 wt%. Electrochemical performance measurements under reversible SOFC operating conditions on a half-cell with 19.7 wt% PBMO-LSGM composite electrodes showed a specific resistance and activation energy significantly lower than those of conventional Ni-based cermet and perovskite-type materials, indicating that the developed PBMO-LSGM composite electrode is a promising electrocatalyst for reversible SOFCs.