No abstract

Schottky barrier heights were calculated for a series of interfaces between transition metals and strontium titanate with the first-principles mixed-basis pseudopotential method based on density functional theory. The process of interface formation was analyzed in a step-by-step procedure that enables to distinguish between structural and electronic contributions influencing the Schottky barrier height. This decomposition yields not only detailed information about the most relevant quantities that determine the band lineup at the interface but provides also means to validate fundamental assumptions of phenomenological theories, which estimate the Schottky barrier height from few characteristic material parameters.

Over-lithiated transition metal oxides are currently the most promising high energy cathode materials. DFT calculations show that Li2MnO3 becomes increasingly unstable upon delithiation and experiences a driving force for either oxygen release from the surface or peroxide formation in the bulk. Both mechanisms are shown to be detrimental for the electrochemistry.