Oxygen vacancies enhanced photocatalytic activity towards VOCs oxidation over Pt deposited Bi2WO6 under visible light

Shuoshuo Zhang; Wenhong Pu; Ayan Chen; Yake Xu; Yunyang Wang; Changzhu Yang; Jianyu Gong

doi:10.1016/j.jhazmat.2019.121478

Oxygen vacancies enhanced photocatalytic activity towards VOCs oxidation over Pt deposited Bi₂WO₆ under visible light

J Hazard Mater. 2020 Feb 15:384:121478. doi: 10.1016/j.jhazmat.2019.121478. Epub 2019 Oct 14.

Authors

Shuoshuo Zhang¹, Wenhong Pu¹, Ayan Chen¹, Yake Xu¹, Yunyang Wang¹, Changzhu Yang¹, Jianyu Gong²

Affiliations

¹ School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China.
² School of Environmental Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, China. Electronic address: jygong@hust.edu.cn.

PMID: 31653408
DOI: 10.1016/j.jhazmat.2019.121478

Abstract

A novel Pt assisted self-modified Bi₂WO₆ composites (Pt/Bi-BWO) with high oxygen vacancies concentration was successfully fabricated via a simple in-situ NaBH₄ reduction method in presence of H₂PtCl₆•6H₂O. The Pt/Bi-BWO performed excellent photocatalytic activity on the degradation of gaseous toluene under visible light illumination. The photocatalytic reaction rate of 0.15% Pt/Bi-BWO was 2.88 times higher than that of Bi₂WO₆. Over 90% gas phase toluene was removed by 0.15% Pt/Bi-BWO in one hour and over 80% of which was degraded into CO₂ and H₂O. The Pt/Bi-BWO also performed great stability confirmed by circulating runs test. The mechanism of the promotion was explored by electron paramagnetic resonance (EPR) and DFT calculations. The produced oxygen vacancies were below conduction band (CB) of Bi₂WO₆, leading to a narrowed band gap. Meantime, the generated oxygen vacancies could activate O₂ to enhance the production of reactive oxygen species (ROS), such as O₂^- and OH. In addition, the added Pt could act as electron trap to suppress the recombination of electrons-holes pairs. In a word, this work produced a novel simply made photocatalyst to remove volatile organic compounds.

Keywords: Bi(2)WO(6); Oxygen vacancies; Photocatalytic oxidation; Pt; VOCs.

Publication types

Research Support, Non-U.S. Gov't