LAMNO3 AIR CATHODES CONTAINING ZRO2 ELECTROLYTE FOR HIGH-TEMPERATURE SOLID OXIDE FUEL-CELLS

This study is an attempt to improve LaMnO3 high temperature air cathodes by using an electrode structure which resembles that of porous electrodes of liquid electrolyte fuel cells. Y2O3-stabilized zirconia (YSZ) was loaded with LaMnO3 and molded into porous electrodes which had YSZ-LAMnO3 interfaces inside the electrodes. A strong relation was seen between the conductivity of YSZ added and polarization losses, suggesting that the internal LaMnO3-YSZ contacts are active for O2 reduction. The addition of YSZ prevents the formation of highly resistive La2Zr2O7 which has otherwise been formed at the electrode-electrolyte interface. This effect also helps to enhance the electrodes.