Synthesis and Electrical Characterization of the Ceramic Anode La1-xSrxMn0.5Cr0.5O3

Abstract

The synthesis and electrical characterization of La1-xSrxMn0.5Cr0.5O3 compounds arereported. These compounds, with perovskite structure, have been pointed out as apromising alternative for the nickel-based cermet anode of Solid Oxide Fuel Cells.Polycrystalline samples, with x = 0.3, 0.4, and 0.5, were prepared by the citrate technique.The crystalline phase and the chemical compatibility with zirconia-based electrolyteswere studied by X-ray diffraction analyses. The electrical properties were studied by 4-probe dc electrical conductivity sigma(T) measurements during redox cycles under bothoxidizing and reducing atmospheres. The main results show that the sigma(T) has a thermallyactivated behavior, and increasing Sr content increases sigma(T). Compounds with x = 0.3exhibited no appreciable chemical reaction with the stabilized zirconia electrolyte afterheat treatment at high temperature. The sigma(T) measurements evidenced the redox stabilityof the ceramic anode. However, some degradation of the Ã(T) was observed on samplesthermally treated at 1000 °C under pure hydrogen (AU)