ECS Proceedings Volumes · 1995 · 13 citations · 0 references
Natural SciencesChemistryMaterials ScienceInorganic ChemistrySolid State PhysicsSolid-state ChemistryInorganic MaterialsMetal OxidesPhase EquilibriaPhase EquilibriumPhase StabilityPhase TransitionsBinary Metal OxidesPhase Equilibria In CeramicsPhase Equilibria In SolutionsQuenched PhasesSolid-solution ThermodynamicsSolid-state Phase EquilibriaTetragonal LatticesTetragonal System
The phase equilibria in La-Sr-Co-O system have been studied in air at 1100°C. The binary oxides found in the system are: LaCoO3, Sr2Co2O5 and Sr3Co2Oz. Sr3Co2Oz was synthesized at the first time and has the tetragonal structure. The solid solutions formed in the system and their compositional ranges were determined as La1−xSrxCoO3−δ (0≤x≤0.8) and (La1−ySry)2CoO4 (0.3≤y≤0.55). The thermodynamic stability of the solid solution at 1100°C were determined as a function of oxygen pressure by X-ray diffraction of the quenched samples and EMF measurements in a galvanic cell with solid electrolyte.