Efficient promotion of charge transfer and separation in hydrogenated TiO2/WO3 with rich surface-oxygen-vacancies for photodecomposition of gaseous toluene

Juan-Juan Li; Bo Weng; Song-Cai Cai; Jing Chen; Hong-Peng Jia; Yi-Jun Xu

doi:10.1016/j.jhazmat.2017.08.077

Efficient promotion of charge transfer and separation in hydrogenated TiO₂/WO₃ with rich surface-oxygen-vacancies for photodecomposition of gaseous toluene

J Hazard Mater. 2018 Jan 15:342:661-669. doi: 10.1016/j.jhazmat.2017.08.077. Epub 2017 Sep 19.

Authors

Juan-Juan Li¹, Bo Weng², Song-Cai Cai³, Jing Chen⁴, Hong-Peng Jia⁵, Yi-Jun Xu⁶

Affiliations

¹ CAS Center for Excellence in Regional Atmospheric Environment, and Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China.
² State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, New Campus, Fuzhou University, Fuzhou 350116, PR China; College of Chemistry, New Campus, Fuzhou University, Fuzhou 350116, PR China.
³ CAS Center for Excellence in Regional Atmospheric Environment, and Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China.
⁴ Xiamen Institute of Rare-earth Materials, Haixi Institutes, Chinese Academy of Sciences, Xiamen, Fujian 361021, PR China.
⁵ CAS Center for Excellence in Regional Atmospheric Environment, and Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China. Electronic address: hpjia@iue.ac.cn.
⁶ State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, New Campus, Fuzhou University, Fuzhou 350116, PR China; College of Chemistry, New Campus, Fuzhou University, Fuzhou 350116, PR China. Electronic address: yjxu@fzu.edu.cn.

PMID: 28898863
DOI: 10.1016/j.jhazmat.2017.08.077

Abstract

Oxygen-deficient TiO₂/WO₃ constructed via the controllable temperature of hydrogen annealing is designed in view of combining the broad visible spectrum absorption with the prominent coupled semiconductor properties. Surface lattice disorder of TiO₂/WO₃ arises at hydrogen annealing temperature of 200 and 300°C, while critical phase transition from TiO₂/WO₃ to TiO₂/WO_2.9 occurs at 400°C, both of which can introduce oxygen vacancies. The hydrogenated TiO₂/WO₃ with rich surface-oxygen-vacancies exhibits much higher photocatalytic activity for decomposition of gaseous toluene than pristine TiO₂/WO₃ under visible-light illumination (λ>420nm). The photoelectrochemical analysis shows that the improved electronic properties of oxygen-deficient TiO₂/WO₃ enable dramatically efficient promotion of photoinduced charge transfer and separation, which is the key factor for the improved photocatalytic activity. It is hoped that the present work could boost ongoing interest for preparing various hydrogenated coupled semiconductors with enhanced activity for diverse photocatalytic applications.

Keywords: Charge transfer and separation; Hydrogenated TiO(2)/WO(3); Photodecomposition of toluene; Surface-oxygen-vacancies; Visible-light.