Study on the electronic structures of the reduced anatase TiO2 by the first-principle calculation

Cheng, Zhijun and Liu, Tingyu and Yang, Chenxing and Gan, Haixiu and Zhang, Feiwu and Cheng, Jianyu. 2012. Study on the electronic structures of the reduced anatase TiO2 by the first-principle calculation. Journal of Physics and Chemistry of Solids. 73 (2): pp. 302-307.

Source Title

Journal of Physics and Chemistry of Solids

DOI

10.1016/j.jpcs.2011.10.020

ISSN

00223697

School

Nanochemistry Research Institute (Research Institute)

Remarks

NOTICE: this is the author’s version of a work that was accepted for publication in Journal of Physics and Chemistry of Solids. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Physics and Chemistry of Solids , 73, (2) 2012. http://dx.doi.org/10.1016/j.jpcs.2011.10.020

URI

http://hdl.handle.net/20.500.11937/9683

Collection

Curtin Research Publications

Abstract

Employing the first-principle calculations based on the density functional theory (DFT) and the Molecule Orbital theory (MO), we have researched the electronic structures of the reduced anatase TiO2 and its visible light photoactivity. The study is emphasized on the O vacancy, including the components of the defect states, the relationship with the bulk states and the way in which these electrons occupying the defect states are distributed in the real space. We find that the origin of the visible light photoactivity should be due to the transition of the excited electrons from the defect states sigma subscript g orbital to the sigma subscript u orbital in the upper conduction bands, rather than arising from the reduction of the band gap. The calculated results indicate that the localized defect states induced by the neutral and doubly ionized oxygen vacancies are all located in the band gap.