The Electronic Structure and Optical Properties of Anatase TiO₂ with Rare Earth Metal Dopants from First-Principles Calculations

Kefeng Xie; Qiangqiang Jia; Yizhe Wang; Wenxue Zhang; Jingcheng Xu

doi:10.3390/ma11020179

The Electronic Structure and Optical Properties of Anatase TiO₂ with Rare Earth Metal Dopants from First-Principles Calculations

Materials (Basel). 2018 Jan 24;11(2):179. doi: 10.3390/ma11020179.

Authors

Kefeng Xie¹, Qiangqiang Jia², Yizhe Wang³, Wenxue Zhang⁴, Jingcheng Xu^{5

6}

Affiliations

¹ State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China. xiekefeng@qhu.edu.cn.
² State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China. 2015990037@qhu.edu.cn.
³ State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China. 2014990051@qhu.edu.cn.
⁴ Lanzhou Petrochemical Research Center, Petrochina, Lanzhou 730060, China. zhangwenxue1@petrochina.com.cn.
⁵ School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China. jchxu@usst.edu.cn.
⁶ Shanghai Innovation Institute for Materials, Shanghai 200444, China. jchxu@usst.edu.cn.

Abstract

The electronic and optical properties of the rare earth metal atom-doped anatase TiO₂ have been investigated systematically via density functional theory calculations. The results show that TiO₂ doped by Ce or Pr is the optimal choice because of its small band gap and strong optical absorption. Rare earth metal atom doping induces several impurity states that tune the location of valence and conduction bands and an obvious lattice distortion that should reduce the probability of electron-hole recombination. This effect of band change originates from the 4f electrons of the rare earth metal atoms, which leads to an improved visible light absorption. This finding indicates that the electronic structure of anatase TiO₂ is tuned by the introduction of impurity atoms.

Keywords: anatase TiO2; electronic and optical properties; rare earth metal atoms.