A strategy of enhancing the photoactivity of TiO₂ containing nonmetal and transition metal dopants

An effective structural codoping approach is proposed to modify the photoelectrochemical (PEC) properties of anatase TiO₂ by being doped with nonmetal (N or/and C) and transition metal (Re) elements. The electronic structures and formation energies of different doped systems are investigated using spin-polarized density functional theory. We find that (C, Re) doped TiO₂, with a low formation energy and a large binding energy, reduces the band gap to a large extent, thus it could contribute to the significant enhancement of the photocatalytic activity in the visible-light region. It should be pointed out that, to be successful, the proper proportion of the dopants C and Re should be controlled, so that reasonable PEC properties can be achieved.