title: Enhanced visible-light-driven photocatalytic activity in yellow and black orthorhombic NaTaO3 nanocubes by surface modification and simultaneous N/Ta(4+) co-doping.
abstract: Perovskite-type NaTaO3 as a wide band semiconductor shows good catalytic activity under UV light irradiation. In this work, chemical manipulation methods including surface modification and elemental doping have been adopted to improve the catalytic activity of NaTaO3 nanocubes for visible-light-driven applications. Firstly, a facile hydrothermal route was established to fabricate uniform NaTaO3 nanocubes with orthorhombic structure, which exhibited narrower band gaps than that of cubic NaTaO3. During this syntheses process, glucose could be used as the local structure modifier to generate modified NaTaO3 nanocubes with increased surface defects. Subsequent annealing treatment in NH3 atmosphere yielded anion (N(3-)) and self- (Ta(4+)) simultaneously doped products with further enhanced photocatalytic response in the visible region. The dramatic red shifts of the band gap of NaTaO3 into the visible region were associated with both the local crystal structure variation and exotic molecular level of the doping elements. The optimized products, black-coloured NaTaO(3-x)N(y), exhibit desirable band gap down to 2.2 eV and excellent photocatalytic activity for the degradation of organic pollutants under visible light irradiation. More importantly, our approach for preparing Ta(4+)/N co-doped NaTaO3 provides a good example for the combination of controllable syntheses routes and chemical doping methods to promote traditional wide-band catalysts for visible-light driven applications.
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China.
authors.forename: Yannan
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China; High Pressure Science and Engineering Center, University of Nevada, Las Vegas, NV 89154, United States. Electronic address: yyggwang@gmail.com.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wen
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China.
authors.forename: Binbin
authors.initials: B
authors.lastname: Chang
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China.
authors.forename: Yanzhen
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Beijing Centre for Crystal Research and Development, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Zheshuai
authors.initials: Z
authors.lastname: Lin
authors.affiliation: Institute of Nanostructured Functional Materials, Huanghe Science and Technology College, Zhengzhou, Henan 450006, China.
authors.forename: Baocheng
authors.initials: B
authors.lastname: Yang
keywords: N-doping; Orthorhombic structure; Perovskite-type NaTaO(3); Self-doping