Cobalt-free perovskite La0.6Ba0.4Ni0.2Fe0.8-xTixO3-δ(x=0–0.3) as cathode for intermediate-temperature solid oxide fuel cells

Abstract

Developing effective cathode materials with superior electrocatalytic properties is crucial for advancing the practical application of solid oxide fuel cells. In this study, we successfully synthesized a series of cathode materials by introducing Ti into La0.6Ba0.4Ni0.2Fe0.8-xTixO3-δ(x = 0, 0.1, 0.2, 0.3) and conducted a comprehensive investigation of their physical and electrochemical characteristics. Our research revealed that the introduction of Ti into these materials led to a significant improvement in electrocatalytic activity and overall electrochemical performance. Importantly, these enhancements were achieved while maintaining an optimal thermal expansion coefficient and exceptional electrode stability. Among the various samples examined, the La0.6Ba0.4Ni0.2Fe0.7Ti0.1O3-δ cathode material stood out with the lowest polarization resistance recorded at 0.153 Ω cm2 and the highest power density achieved at 800 °C, reaching an impressive 1068 mW/cm2. Furthermore, our long-term stability tests demonstrated that these cells exhibited remarkable electrode stability, with no significant deterioration in electrochemical performance observed over a testing period of 50 h. Based on these findings, we propose that La0.6Ba0.4Ni0.2Fe0.7Ti0.1O3-δ holds great promise as a potential cathode material for solid oxide fuel cells.