Combustion synthesis of LaNi_(0.6)Fe_(0.4)O3 perovskite as cathode contact material for IT-SOFCs

摘要

A perovskite sample of composition LaNi_(0.6)Fe_(0.4)O3 has been prepared by the glycine-nitrate route using different amounts of glycine fuel (G/N= 0.5, 1.0 and 1.5), in order to study the sample preparation influence on the structural, morphological and electrical properties in the context of their possible use as cathode contact material for intermediate temperature solid oxide fuel cells (IT-SOFCs). The obtained materials have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), thermal expansion coefficient (TEC) and electrical conductivity measurements. X-ray powder diffraction (XRD) shows that all of the compounds have rhombohedral symmetry (space group: R-3c). All of the samples obtained using different amounts of glycine fuel have a porous microstructure with fine grain sizes. The data obtained by bulk conductivity showed that the sample obtained at the glycine/nitrate ratio 1.0 presents more suitable conductivity values for application as SOFC contact material.