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Title: Ab initio studies of Nb–N–S tri-doped TiO{sub 2} with enhanced visible light photocatalytic activity

Abstract

The electronic and optical properties of Nb–N–S tri-doped anatase TiO{sub 2} were investigated within the frame of the density functional theory (DFT) plus U method. Results show that a significant red-shift effect and improvement of visible-light absorption for Nb–N–S tri-doped TiO{sub 2} are observed with respect to pure TiO{sub 2} and S–N codoped TiO{sub 2}. At the same time, the enhanced visible-light photocatalytic activity of tri-doped TiO{sub 2} is derived from the narrowing band gap, the appearance of Nb 4d state at the bottom of conduction band and the mixture of N 2p, S 3p states forming new defect levels at the top of valance band, which is excellently consistent with the previous experiment. Moreover, S ion leads to the lattice distortion and promotes the visible-light photocatalytic activity. Furthermore, the absorbance of 1.39NbNS–TiO{sub 2} accords well with the experimental result in the visible region. It is also found that the 2.78NbNS–TiO{sub 2} can be easily grown under O-rich condition and have the strongest absorbance from 2.0 to 4.2 eV among four models.

Authors:
;  [1];  [1];  [2]
  1. Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22584107
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 238; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABSORPTION; COMPUTER CALCULATIONS; DENSITY FUNCTIONAL METHOD; DOPED MATERIALS; ELECTRONIC STRUCTURE; MIXTURES; NIOBIUM COMPOUNDS; NITROGEN COMPOUNDS; OPTICAL PROPERTIES; PHOTOCATALYSIS; SULFUR COMPOUNDS; TITANIUM OXIDES

Citation Formats

Ren, Dahua, Cheng, Junxia, Cheng, Xinlu, E-mail: chengxl@scu.edu.cn, and Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064. Ab initio studies of Nb–N–S tri-doped TiO{sub 2} with enhanced visible light photocatalytic activity. United States: N. p., 2016. Web. doi:10.1016/J.JSSC.2016.03.020.
Ren, Dahua, Cheng, Junxia, Cheng, Xinlu, E-mail: chengxl@scu.edu.cn, & Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064. Ab initio studies of Nb–N–S tri-doped TiO{sub 2} with enhanced visible light photocatalytic activity. United States. doi:10.1016/J.JSSC.2016.03.020.
Ren, Dahua, Cheng, Junxia, Cheng, Xinlu, E-mail: chengxl@scu.edu.cn, and Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064. 2016. "Ab initio studies of Nb–N–S tri-doped TiO{sub 2} with enhanced visible light photocatalytic activity". United States. doi:10.1016/J.JSSC.2016.03.020.
@article{osti_22584107,
title = {Ab initio studies of Nb–N–S tri-doped TiO{sub 2} with enhanced visible light photocatalytic activity},
author = {Ren, Dahua and Cheng, Junxia and Cheng, Xinlu, E-mail: chengxl@scu.edu.cn and Key Laboratory of High Energy Density Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064},
abstractNote = {The electronic and optical properties of Nb–N–S tri-doped anatase TiO{sub 2} were investigated within the frame of the density functional theory (DFT) plus U method. Results show that a significant red-shift effect and improvement of visible-light absorption for Nb–N–S tri-doped TiO{sub 2} are observed with respect to pure TiO{sub 2} and S–N codoped TiO{sub 2}. At the same time, the enhanced visible-light photocatalytic activity of tri-doped TiO{sub 2} is derived from the narrowing band gap, the appearance of Nb 4d state at the bottom of conduction band and the mixture of N 2p, S 3p states forming new defect levels at the top of valance band, which is excellently consistent with the previous experiment. Moreover, S ion leads to the lattice distortion and promotes the visible-light photocatalytic activity. Furthermore, the absorbance of 1.39NbNS–TiO{sub 2} accords well with the experimental result in the visible region. It is also found that the 2.78NbNS–TiO{sub 2} can be easily grown under O-rich condition and have the strongest absorbance from 2.0 to 4.2 eV among four models.},
doi = {10.1016/J.JSSC.2016.03.020},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 238,
place = {United States},
year = 2016,
month = 6
}
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