First-principles study of the electronic structures and magnetic properties of 3d transition metal-dopedanatase TiO2

Abstract

We study the electronic structures and magnetic properties of the anataseTiO2 doped with 3d transition metals (V, Cr, Mn, Fe, Co, Ni), using first-principlestotal energy calculations based on density functional theory (DFT). Using amolecular-orbital bonding model, the electronic structures of the doped anataseTiO2 are well understood. A band coupling model based on d–d level repulsions between thedopant ions is proposed to understand the chemical trend of the magnetic ordering.Ferromagnetism is found to be stabilized in the V-, Cr-, and Co-doped samples if there areno other carrier native defects or dopants. The ferromagnetism in the Cr- andCo-doped samples may be weakened by the donor defects. In the Mn-, and Fe-dopedsamples, the ferromagnetism can be enhanced by the acceptor and donor defects,respectively.