Adsorption of Li₂O₂, Na₂O₂, and NaO₂ on TiC(111) Surface for Metal–Air Rechargeable Batteries: A Theoretical Study

Abstract

We analyze, with density functional theory calculations, the adsorption energies of Li2O2, Na2O2, and NaO2 on clean and oxygen-passivated TiC (111) surfaces. We show that after deposition of two molecular layers of alkali metal oxides, the initial state of the TiC surface becomes unimportant for the adsorption energy and that all adsorption energies approach their native crystal values. The structure of the adsorbed molecular layers is analyzed and compared with their native oxide crystal structure. Finally, we discuss the similarities and differences of Li peroxide and Na oxides adsorption at the electrode surface.