First-principles study on electronic, magnetic properties and optical absorption of vanadium doped rutile TiO2

Abstract

The electronic, magnetic properties and optical absorption of vanadium (V) doped rutile TiO2 have been studied by the generalized gradient approximation GGA and GGA+U (Hubbard coefficient) approach respectively. On the one hand, we consider the influence of vanadium with different doping concentration on the electronic structure. On the other hand, we study double V atoms doped TiO2, mainly study four V-doped TiO2 configurations, and find the magnetic ground states are ferromagnetic state. For the TiO2@V-V1, TiO2@V-V3 and TiO2@V-V4 configurations without O ion as bridge between V-V atoms, there will have a metastable state of antiferromagnetic configurations, while, for the TiO2@V-V2 configurations with an O ion as bridge between V-V atoms, due to the existence of superexchange between V-O-V, there will only exist the ground state of ferromagnetic state and there are no other metastable configurations. Furthermore, the optical properties of V-doped TiO2 are calculated. The results show that the V-doped TiO2 has strong infrared light absorption and visible light absorption.