Designing and fabricating a CdS QDs/Bi2MoO6 monolayer S-scheme heterojunction for highly efficient photocatalytic C2H4 degradation under visible light

Xinyue Xu; Yanghang Su; Yuanpeng Dong; Xiao Luo; Shihao Wang; Wenyu Zhou; Rong Li; Kevin Peter Homewood; Xiaohong Xia; Yun Gao; Xuxing Chen

doi:10.1016/j.jhazmat.2021.127685

Designing and fabricating a CdS QDs/Bi₂MoO₆ monolayer S-scheme heterojunction for highly efficient photocatalytic C₂H₄ degradation under visible light

J Hazard Mater. 2022 Feb 15;424(Pt D):127685. doi: 10.1016/j.jhazmat.2021.127685. Epub 2021 Nov 6.

Authors

Xinyue Xu¹, Yanghang Su¹, Yuanpeng Dong¹, Xiao Luo², Shihao Wang¹, Wenyu Zhou¹, Rong Li³, Kevin Peter Homewood¹, Xiaohong Xia¹, Yun Gao⁴, Xuxing Chen⁵

Affiliations

¹ Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China.
² Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China; School of Sciences, Hubei University of Automotive Technology, Shiyan 442002, China.
³ Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China; State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China. Electronic address: rli@hubu.edu.cn.
⁴ Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China. Electronic address: gaoyun@hubu.edu.cn.
⁵ Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials, School of Materials Science & Engineering, Hubei University, Wuhan 430062, China. Electronic address: cxx0613@hubu.edu.cn.

PMID: 34799172
DOI: 10.1016/j.jhazmat.2021.127685

Abstract

Achieving efficient photocatalytic degradation of atmospheric volatile organic compounds (VOCs) under sun-light is still a significant challenge for environmental protection. The S-scheme heterojunction with its unique charge migration route, high charge separation rate and strong redox ability, has great potential. However, how to regulate interfacial charge transfer of the S-scheme heterojunction is of significant importance. Here, density functional theory (DFT) calculations were first conducted and predicted that an S-scheme heterojunction could be formed in the CdS quantum dots/Bi₂MoO₆ monolayer system. Subsequently, this novel heterojunction is constructed by in-situ hydrothermal synthesis of CdS quantum dots on monolayer Bi₂MoO₆. Under visible-light, this novel S-scheme system gives a high-efficiency photocatalytic degradation rate (6.04 × 10^-2 min^-1) towards C₂H₄, which is 30.3 times higher than that of pure CdS (1.99 × 10^-3 min^-1) and 41.7 times higher than pure Bi₂MoO₆ (1.45 × 10^-3 min^-1). Strong evidence for the S-scheme charge transfer path is provided by in-situ XPS, PL, TRPL and EPR.

Keywords: Bi(2)MoO(6) monolayer; CdS QDs; Photocatalysis; S-scheme; VOCs.