Oxidation of graphite by atomic oxygen: a first-principles approach

The main goal of this paper is to investigate the interaction of atomic oxygen with graphite surfaces, using first principles total energy calculations. Oxygen coverage, position and crystallographic orientation of the surfaces are the main parameters of this study. At the basal surface, the binding energy is given by the contribution of the in-network interaction between oxygen atoms and between oxygen and graphite. Relaxation effects are non-negligible at low and medium coverages. Zig-zag surfaces are the most reactive ones, followed by armchair and basal ones. For both surfaces, the oxidative etching process that forms the CO and CO2 gases is also discussed on the basis of our calculations.