Electronic band structures of TiO₂ with heavy nitrogen doping

Abstract

The first-principles density-functional calculation was conducted to investigate the electronic band structures of titanium dioxide with heavy nitrogen doping (TiO_2−xN _x). The calculation results indicate that when x ⩽ 0.25, isolated N 2p states appear above the valence-band maximum of TiO₂ without a band-gap narrowing between O 2p and Ti 3d states. When x ⩾ 0.50, an obvious band gap narrowing between O 2p and Ti 3d states was observed along with the existence of isolated N 2p states above the valence-band of TiO₂, indicating that the mechanism proposed by Asahi et al operates under heavy nitrogen doping condition.

Keywords

computer simulation / dopanted TiO₂ / band structure

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