S-scheme Cu3P/TiO2 heterojunction for outstanding photocatalytic water splitting

Kexin Wang; Zhongge Luo; Bin Xiao; Tong Zhou; Jianhong Zhao; Congcong Shen; Dequan Li; Zhishi Qiu; Jin Zhang; Tianwei He; Qingju Liu

doi:10.1016/j.jcis.2023.08.174

S-scheme Cu₃P/TiO₂ heterojunction for outstanding photocatalytic water splitting

J Colloid Interface Sci. 2023 Dec 15;652(Pt B):1908-1916. doi: 10.1016/j.jcis.2023.08.174. Epub 2023 Aug 29.

Authors

Kexin Wang¹, Zhongge Luo¹, Bin Xiao¹, Tong Zhou¹, Jianhong Zhao¹, Congcong Shen¹, Dequan Li¹, Zhishi Qiu¹, Jin Zhang¹, Tianwei He¹, Qingju Liu²

Affiliations

¹ Yunnan Key Laboratory for Micro/Nano Materials & Technology, National Center for International Research on Photoelectric and Energy Materials, School of Materials and Energy, Yunnan University, Kunming 650091, China.
² Yunnan Key Laboratory for Micro/Nano Materials & Technology, National Center for International Research on Photoelectric and Energy Materials, School of Materials and Energy, Yunnan University, Kunming 650091, China. Electronic address: qjliu@ynu.edu.cn.

PMID: 37690298
DOI: 10.1016/j.jcis.2023.08.174

Abstract

TiO₂ photocatalysts are of great interest in the fields of environmental purification, new energy and so on, because of their non-toxicity, high stability, high redox ability and low cost. However, the photogenerated carriers are severely recombined, which limits the application of TiO₂ photocatalysts. Herein, S-scheme Cu₃P/TiO₂ heterojunction composites were successfully synthesized by a simple and efficient microwave hydrothermal method, and the results show that the hydrogen production rate of Cu₃P/TiO₂ is 5.83 mmol∙g^-1∙h^-1 under simulated sunlight irradiation, which is 7.3 and 83.3 times higher than that of pure TiO₂ and Cu₃P, respectively. This excellent performance is derived from the internal electric field (IEF) and energy band bending generated by the S-scheme heterojunction formed between Cu₃P and TiO₂. The density functional theory (DFT) calculation indicates that the Cu₃P possess smaller work function and more negative conduction band (CB) position than that of TiO₂, which is very conducive to greatly improve the H⁺ reduction ability and hydrogen production performance. This work provides a new idea for the reveal of electron transfer paths and active sites in S-scheme heterojunctions and deepens the mechanism understanding.

Keywords: Directional modulation of photogenerated electrons; Photocatalytic hydrogen production; S-scheme heterojunction; Suppression of carrier recombination.