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Electronic and magnetic properties of V-doped anatase TiO$_{2}$ from first principles

Xiaosong Du·Qunxiang Li·Haibin Su·Jinlong Yang
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Abstract

We report a first-principles study on the geometric, electronic and magnetic properties of V-doped anatase TiO$_{2}$. The DFT+U (Hubbard coefficient) approach predicts semiconductor band structures for Ti$_{1-x}$V$_{x}$O$_{2}$ (x=6.25 and 12.5%), in good agreement with the poor conductivity of samples, while the standard calculation within generalized gradient approximation fails. Theoretical results show that V atoms tend to stay close and result in strong ferromagnetism through superexchange interactions. Oxygen vacancy induced magnetic polaron could produce long-range ferromagnetic interaction between largely separated magnetic impurities. The experimentally observed ferromagnetism in V-doped anatase TiO$_{2}$ at room temperature may originate from a combination of short-range superexchange coupling and long-range bound magnetic polaron percolation.

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Xiaosong Du, Qunxiang Li, Haibin Su, Jinlong Yang. 2006-12-08. Electronic and magnetic properties of V-doped anatase TiO$_{2}$ from first principles. https://doi.org/10.1103/physrevb.74.233201

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