Evaluation of LaSr2Fe2CrO9-δ as a Potential Electrode for Symmetrical Solid Oxide Fuel Cells

Structure stability and electrical conductivity of LaSr2Fe2CrO9-δ were investigated in air and in hydrogen to explore its potential applications as symmetrical electrodes for solid oxide fuel cells. X-Ray diffraction measurements showed that LaSr2Fe2CrO9-δ was essentially stable despite the presence of minor LaSrFeO4 impurities after heat-treated in humidified hydrogen at 800 °C. LaSr2Fe2CrO9-δ-based symmetrical fuel cells fabricated on LSGM electrolyte substrates via screen printing achieved a maximum power density of 224 mW cm−2. After using a composite electrode (50 wt% LaSr2Fe2CrO9-δ–50 wt% Gd0.2Ce0.8O2-δ), both the anode and the cathode polarization resistances decreased. The maximum power density of symmetrical fuel cells using LaSr2Fe2CrO9-δ–Gd0.2Ce0.8O2-δ composite electrodes increased to 264 mW/cm2 and the corresponding total cell polarization resistance was 0.454 Ω cm2 at 800 °C with humidified hydrogen fuels and ambient air oxidants.