O2 Adsorption and Dissociation on A Hydrogenated Anatase (101) Surface

O2 adsorption and dissociation on a hydrogenated anatase (101) surface are studied with first-principle calculations coupled with the nudged elastic band (NEB) method. H atoms on the anatase (101) surface or at subsurface sites can increase the absolute values of the O2 adsorption energy. The O2 dissociation barriers on an anatase surface with two H atoms at the subsurface sites or with a H surface adatom and a subsurface atom are much lower than that of the dissociation on a surface with H adatoms on the (101) surface. After the dissociation, OH, H2O, and O adatoms may form on the surface. Because it is not difficult for H adatoms on the surface to diffuse to the subsurface sites, surface H doping atoms are very useful to reduce the O2 dissociation barrier. The anatase particles with hydrogenated (101) surface are efficient catalysts to oxidize the adsorbed toxic gas molecule.