Interfacial engineering of Ti3C2 MXene/CdIn2S4 Schottky heterojunctions for boosting visible-light H2 evolution and Cr(VI) reduction

Chao Liu; Wen Xiao; Guiyun Yu; Qiang Wang; Jiawei Hu; Chenghao Xu; Xinyi Du; Jianguang Xu; Qinfang Zhang; Zhigang Zou

doi:10.1016/j.jcis.2023.02.137

Interfacial engineering of Ti₃C₂ MXene/CdIn₂S₄ Schottky heterojunctions for boosting visible-light H₂ evolution and Cr(VI) reduction

J Colloid Interface Sci. 2023 Jun 15:640:851-863. doi: 10.1016/j.jcis.2023.02.137. Epub 2023 Feb 28.

Authors

Chao Liu¹, Wen Xiao², Guiyun Yu³, Qiang Wang², Jiawei Hu², Chenghao Xu², Xinyi Du², Jianguang Xu⁴, Qinfang Zhang⁵, Zhigang Zou⁶

Affiliations

¹ School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China. Electronic address: cliu@ycit.edu.cn.
² School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China.
³ School of Chemistry & Chemical Engineering, Yancheng Institute of Technology, Yancheng, 224051, PR China.
⁴ School of Energy and Materials, Shanghai Polytechnic University, Shanghai 201209, PR China. Electronic address: xujg@sspu.edu.cn.
⁵ School of Materials Science and Engineering, Yancheng Institute of Technology, Yancheng 224051, PR China. Electronic address: qfangzhang@ycit.edu.cn.
⁶ Eco-Materials and Renewable Energy Research Centre (ERERC), School of Physics, Nanjing University, Nanjing 210093, PR China.

PMID: 36905894
DOI: 10.1016/j.jcis.2023.02.137

Abstract

Developing efficient heterojunction photocatalysts that have a high charge carrier separation rate and improved light-harvesting capacity is a crucial step in solving energy crisis and reducing environmental pollution. Herein, we synthesized few-layered Ti₃C₂ MXene sheets (MXs) by a manual shaking process, and combined with CdIn₂S₄ (CIS) to construct novel Ti₃C₂ MXene/CdIn₂S₄ (MXCIS) Schottky heterojunction through a solvothermal method. The strong interface between two-dimensional (2D) Ti₃C₂ MXene and 2D CIS nanoplates led to enhanced light-harvesting capacity and promoted charge separation rate. Additionally, the presence of S vacancies on the MXCIS surface helped to trap free electrons. The optimal sample, 5-MXCIS (with 5 wt% MXs loading), exhibited outstanding performance for photocatalytic hydrogen (H₂) evolution and Cr(VI) reduction under visible light due to the synergistic effect of enhanced light-harvesting capacity and charge separation rate. The charge transfer kinetics was thoroughly studied using multiple techniques. The reactive species of ^•O₂^-, ^•OH and h⁺ were generated in 5-MXCIS system, and e^- and ^•O₂^- radicals were found to be the main contributors to Cr(VI) photoreduction. Based on the characterization results, a possible photocatalytic mechanism for H₂ evolution and Cr(VI) reduction was proposed. On the whole, this work provides new insights into the design of 2D/2D MXene-based Schottky heterojunction photocatalysts for boosting photocatalytic efficiency.

Keywords: CdIn(2)S(4); Cr(VI) photoreduction; Hydrogen evolution; MXene; Photocatalysis.