Study of a Promising Co-Doped Double Perovskite Cathode Material for IT-SOFCs

Abstract

Based on the high catalytic activity and mixed ionic and electronic conductivity, double layered perovskites have been recognized as advanced cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs). A recent study has outlined that the synergic effect of co-doping high valence cations (Nb5+ and Ta5+) on a simple perovskite (SrCo1.8Ta0.1Nb0.1O5+δ) has created an optimal balance of oxygen vacancies, ionic mobility and surface electron transfer which results with a drop of the ASR and a promising power density of the fuel cell. In this study, a co-doped double layered perovskite, LnBa0.5Sr0.5Co1.8Ta0.1Nb0.1O5+δ (Ln = Sm and Pr), was evaluated as IT-SOFC cathode material. The properties of the materials were analyzed with yttria stabilized zirconia and gadolinium-doped ceria electrolytes. As result, the Ta-Nb co-doped materials exhibits excellent chemical compatibility with typical electrolyte material and good electrochemical performance over 100 hours, making them as a promising cathode material for applications in IT-SOFCs.