Improving Oxygen Transport in Perovskite-Type LaGaO₃ Solid Electrolyte through Strain

Lattice strain is a promising possibility to improve materials performance in view of their application in thin-film devices. In particular, defect and transport properties in ionic conductors may be tailored through strain effects, since defect formation energy and migration barriers are correlated to structural parameters which, in turn, are influenced by strain-induced deformations. In this computational study we predicted that oxide-ion diffusion in perovskite-type lanthanum gallate can be improved through application of tensile strain. The structural deformations required to accommodate tensile lattice strain in the perovskite system are shown to result in a preferential localization of the oxygen vacancies in the equatorial plane of the GaO 6 octahedra, while oxide-ion diffusion becomes anisotropic.