Role of Hole Doping on the Oxygen Vacancy Formation and Migration in LaCoO3

Monday, 27 July 2015
Hall 2 (Scottish Exhibition and Conference Centre)
O. A. Salawu, L. Gan, and U. Schwingenschlogl (King Abdullah university of science and technology)
The LaCoO3 class of materials is of interest for cathodes of solid oxide fuel cells. Spin-polarized
density functional theory is applied to cubic La0.75 (Mg/Ca/Ba)0.25 CoO3 . The effect of this cation
doping on the electronic and magnetic properties as well as oxygen vacancy formation energy is
studied. Oxygen vacancies with proximity to the dopant are energetically favourable in most cases.
We discuss the effect of distortions of the CoO6 octahedron on the electronic structure and the
formation energy of oxygen vacancies. The order of formation oxygen is found to be Mg > Ca >
Ba. Cation doping incorporates holes to the Co-O network which enhances the oxygen vacancy and migration.