Oxygen transport in epitaxial La0.875Sr0.125CoO3-delta thin-film cathodes for solid oxide fuel cells: Roles of anisotropic strain

Abstract

We use first-principles calculation to investigate the influence of lattice strain on the oxygen vacancy and the migration energies in La1-xSrCoO3-delta via a realistic approach using the Poisson's ratio. In the calculation of the vacancy formation energy, it was found that the oxygen sites in the major axis are favorable for achieving vacancy under tensile conditions, while those in the minor axis are in favor of vacancy formation under compressive conditions. The migration energy calculations for oxygen vacancy are also carried out and this reveals interesting strain dependence, higher activation energy when compressive strain is applied in the lateral direction.