Solid-state compatibility of Ca:LaNbO4 with perovskite cathodes: Evidences from X-ray microspectroscopy

The solid-state compatibility between calcium-doped lanthanum niobate and three perovskite cathode materials was investigated using two X-ray microbeam techniques, micro fluorescence absorption spectroscopy. powders (lanthanum strontium ferrite, either cobalt or copper-doped, cobaltite) in contact with the dense electrolyte pellet were annealed at 1150°C for 12–144 h to simulate effect of thermal stresses due fabrication long-term operation. As a result, several interdiffusion phenomena then observed on bilayer cross-sections: particular, chemical state coordination environment calcium, iron, niobium probed space-resolved ab initio modeling near-edge spectra reveal that cation is facilitated by structural flexibility structure, which able accommodate variety foreign cations different oxidation states. Limited stability high-temperatures found all candidate compositions niobate.