First-principles calculation of electronic structure of V-doped anatase TiO2

The energetic and electronic structures of V-doped anatase TiO2 have been investigated systematically by the GGA+U approach, including replacement of Ti by V in the absence and presence of oxygen vacancies and the presence of an interstitial site. It was found that V should exist as a V4+ ion in the replacement of Ti in the anatase lattice, the electron transitions of which to the conduction band from V 3d states are responsible for the experimentally observed visible-light absorption. The influence of V dopant concentration on the electronic and magnetic properties is also discussed, such as the influence of the U value in systems containing oxygen vacancies and spin flip phenomena for interstitial V-doping.