Chinese Journal of Catalysis ›› 2021, Vol. 42 ›› Issue (1): 25-36.DOI: 10.1016/S1872-2067(20)63600-2

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Constructing low-cost Ni3C/twin-crystal Zn0.5Cd0.5S heterojunction/homojunction nanohybrids for efficient photocatalytic H2 evolution

Rongchen Shena, Yingna Dingb, Shibang Lib, Peng Zhangc, Quanjun Xiangd, Yun Hau Nge,#(), Xin Lia,b,*()   

  1. aCollege of Forestry and Landscape Architecture, Key Laboratory of Energy Plants Resource and Utilization, Ministry of Agriculture, South China Agricultural University, Guangzhou 510642, Guangdong, China
    bCollege of Materials and Energy, South China Agricultural University, Guangzhou 510642, Guangdong, China
    cState Center for International Cooperation on Designer Low-Carbon & Environmental Materials (CDLCEM), School of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, Henan, China
    dState Key Laboratory of Electronic Thin Film and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, Sichuan, China
    eSchool of Energy and Environment, City University of Hong Kong, Hong Kong SAR
  • Received:2020-03-02 Accepted:2020-04-21 Online:2021-01-18 Published:2021-01-18
  • Contact: Yun Hau Ng,Xin Li
  • About author:#E-mail: yunhau.ng@cityu.edu.hk
    *Tel: +86-20-85282633; Fax: +86-20-85285596; E-mail: Xinliscau@yahoo.com;
  • Supported by:
    National Natural Science Foundation of China(21975084);National Natural Science Foundation of China(51672089);Specical Funding on Applied Science and Technology in Guangdong(2017B020238005);State Key Laboratory of Advanced Technology for Material Synthesis and Processing (Wuhan University of Technology)(2015-KF-7);Hong Kong Research Grant Council (RGC) General Research Fund(GRF13054)

Abstract:

The development of low-cost semiconductor photocatalysts for highly efficient and durable photocatalytic H2 evolution under visible light is very challenging. In this study, we combine low-cost metallic Ni3C cocatalysts with twin nanocrystal Zn0.5Cd0.5S (ZCS) solid solution homojunctions for an efficient visible-light-driven H2 production by a simple approach. As-synthesized Zn0.5Cd0.5S-1% Ni3C (ZCS-1) heterojunction/homojunction nanohybrid exhibited the highest photocatalytic H2-evolution rate of 783 μmol h-1 under visible light, which is 2.88 times higher than that of pristine twin nanocrystal ZCS solid solution. The apparent quantum efficiencies of ZCS and ZCS-1 are measured to be 6.13% and 19.25% at 420 nm, respectively. Specifically, the homojunctions between the zinc blende and wurtzite segments in twin nanocrystal ZCS solid solution can significantly improve the light absorption and separation of photogenerated electron-hole pairs. Furthermore, the heterojunction between ZCS and metallic Ni3C NP cocatalysts can efficiently trap excited electrons from ZCS solid solution and enhance the H2-evolution kinetics at the surface for improving catalytic activity. This study demonstrates a unique one-step strategy for constructing heterojunction/homojunction hybrid nanostructures for a more efficient photocatalytic H2 evolution compared to other noble metal photocatalytic systems.

Key words: Photocatalytic H2 evolution, Zn0.5Cd0.5S solid solution, Twin nanocrystal, Heterojunction/homojunction, Earth-abundant Ni3C cocatalysts