Construction of S-scheme CdS/g-C3N4 nanocomposite with improved visible-light photocatalytic degradation of methylene blue

Kim Nguyen Van; Ha Tran Huu; Viet Nga Nguyen Thi; Thanh-Lieu Thi Le; Quoc Dat Hoang; Quoc Viet Dinh; Vien Vo; Dai Lam Tran; Yasser Vasseghian

doi:10.1016/j.envres.2021.112556

Construction of S-scheme CdS/g-C₃N₄ nanocomposite with improved visible-light photocatalytic degradation of methylene blue

Environ Res. 2022 Apr 15:206:112556. doi: 10.1016/j.envres.2021.112556. Epub 2021 Dec 22.

Authors

Kim Nguyen Van¹, Ha Tran Huu², Viet Nga Nguyen Thi³, Thanh-Lieu Thi Le², Quoc Dat Hoang⁴, Quoc Viet Dinh², Vien Vo⁵, Dai Lam Tran⁶, Yasser Vasseghian⁷

Affiliations

¹ Faculty of Natural Sciences, Quy Nhon University, Quy Nhon, 55000, Binh Dinh, Viet Nam. Electronic address: nguyenvankim@qnu.edu.vn.
² Faculty of Natural Sciences, Quy Nhon University, Quy Nhon, 55000, Binh Dinh, Viet Nam.
³ Faculty of Education, Quy Nhon University, Quy Nhon, 55000, Binh Dinh, Viet Nam.
⁴ Vietnam Ministry of Science and Technology, 113 Tran Duy Hung, Cau Giay, Hanoi, 10000, Viet Nam.
⁵ Faculty of Natural Sciences, Quy Nhon University, Quy Nhon, 55000, Binh Dinh, Viet Nam. Electronic address: vovien@qnu.edu.vn.
⁶ Institute for Tropical Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Hanoi, Viet Nam.
⁷ Department of Chemical Engineering, Quchan University of Technology, Quchan, Iran.

PMID: 34951992
DOI: 10.1016/j.envres.2021.112556

Abstract

Within moderate band gap, g-C₃N₄ and CdS are both promising visible light driven photocatalysts. However, their intrinsic high recombination rate of photo-induced electron-hole pairs along with the poor susceptibility in photocorrosion of CdS is main limitations hindering their practical application. In this study, the CdS/g-C₃N₄ composites with various weight ratios of CdS to g-C₃N₄ were solvothermal prepared from the dispersion of components, g-C₃N₄ and CdS, in ethanol. The physicochemical characterizations demonstrate the success in the fabrication of well-dispersed CdS nanoparticles in the g-C₃N₄ matrix. The enhanced photocatalytic activity of the g-C₃N₄/CdS composite over the degradation of methylene blue under visible light was ascribed to the effective photo-induced electron-hole separation via the step scheme (S-scheme) pathway in which the main contribution of high oxidative hydroxyl radicals (^•OH) was demonstrated. Furthermore, via S-scheme model, we also clarify the depletion of photo-induced holes on CdS which is ascribed as the reason for improvement in resistance to photocorrosion of composites.

Keywords: CdS/g-C(3)N(4); Photocatalysis; S-scheme; Visible light.

Publication types

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