Sintering temperature dependence of conductivity, porosity and specific surface area of LaNi_0.6Fe_0.4O₃ ceramics as cathode material for solid oxide fuel cells - Superiority of Pechini method among various solution mixing processes

The sintering temperature dependence of the porosity, specific surface area and electrical conductivity of LaNi_0.6Fe_0.4O₃, which is one of the candidate materials for solid oxide fuel cells (SOFC) cathodes, prepared by Pechini method has been investigated. From a comparison of the sintering property, specific surface area and electrical conductivity with those of specimens prepared by other preparation methods, it has been revealed that the Pechini method and co-precipitation (CP) route are the most suitable methods for the preparation of LaNi_0.6Fe_0.4O₃ ceramic for SOFC cathode. The superior properties of the specimens prepared by the Pechini method and CP route can be attributed to the homogeneous cation distribution in the precursor, resulting in lower temperature required for sintering, at which the abnormal grain growth does not occur and a homogeneous grain size can be obtained.