关键词: 锐钛矿TiO2(101)面/
过渡金属掺杂/
电子结构/
光学性质
English Abstract
Modification of the photocatalytic properties of anatase TiO2 (101) surface by doping transition metals
Su Qiao-Zhi1,2,Han Qing-Zhen2,
Gao Jin-Hua1,2,
Wen Hao2,
Jiang Zhao-Tan1
1.School of Physics, Beijing Institute of Technology, Beijing 100081, China;
2.State Key Laboratory of Multiphase Complex System, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 11504374, 11274040) and the Innovation Program of Institute of Process Engineering Chinese Academy of Sciences (Grant No. COM2015A001).Received Date:08 November 2016
Accepted Date:14 December 2016
Published Online:05 March 2017
Abstract:Exploring new types of photocatalysts and modifying the photocatalytic activity have attracted more and more extensive attention in many research fields. Anatase TiO2, a promising photocatalyst widely studied, can only absorb the ultraviolet light and thus only make little use of the power in visible light. Therefore, it is an urgent task to make theoretical and experimental investigations on the photocatalytic mechanism in anatase TiO2 and then improve its visible light response so as to utilize more visible light. Now, in the present paper, we carry out a systematic theoretical investigation on modifying the photocatalytic properties of the anatase TiO2 (101) surface via doping transition metal neutral atoms such as Fe, Ni, Pd, Pt, Cu, Ag, and Au by using the plane wave ultrasoft pseudopotential method of the density functional theory. The dependence of the macroscopic catalytic activity on electronic structure and optoelectronic property is uncovered by making a comparative analysis of the geometric structures, the electronic structures, and the optical properties of the undoped and doped anatase TiO2 (101) surfaces. Our numerical results show that doping certain transition metals can suppress the band gap or induce extra impurity energy levels, which is beneficial to improving the visible light response of the TiO2 (101) surface in different ways. In most cases, the new impurity energy levels will appear in the original band gap, which comes from the contribution of the d electronic states in the transition metal atoms. Moreover, the photocatalytic activity of the TiO2 (101) surface can be changed differently by doping different transition metal atoms, which is closely dependent on the bandgap width, Fermi energy, the impurity energy level, and the electron configuration of the outermost shell of the dopants. This research should be an instructive reference for designing TiO2 (101) photocatalyst and improving its capability, and also helpful for understanding doping transition metal atoms in other materials.
Keywords: anatase TiO2 (101) surface/
transition metal doping/
electronic structure/
optical properties
