Chinese Journal of Catalysis ›› 2021, Vol. 42 ›› Issue (1): 37-45.DOI: 10.1016/S1872-2067(20)63633-6

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Sulfur-mediated photodeposition synthesis of NiS cocatalyst for boosting H2-evolution performance of g-C3N4 photocatalyst

Min Wanga, Jingjing Chenga, Xuefei Wanga,*(), Xuekun Hongb, Jiajie Fanc, Huogen Yua,d,#()   

  1. aDepartment of Chemistry, School of Chemistry, Chemical Engineering and Life Sciences, Wuhan University of Technology, Wuhan 430070, Hubei, China
    bCollege of Physics and Electronic Engineering, Changshu Institute of Technology, Changshu 215500, Jiangsu, China
    cSchool of Materials Science and Engineering, Zhengzhou University, Zhengzhou 450001, Henan, China
    dState Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, Hubei, China
  • Received:2020-01-24 Accepted:2020-03-06 Online:2021-01-18 Published:2021-01-18
  • Contact: Xuefei Wang,Huogen Yu
  • About author:#E-mail: yuhuogen@whut.edu.cn
    *Tel: +86-27-87756662, Fax: +86-27-87879468; E-mail: xuefei@whut.edu.cn;
  • Supported by:
    National Natural Science Foundation of China(51672203);Fundamental Research Funds for the Central Universities(WUT2019IB002);Fundamental Research Funds for the Central Universities(185220002)

Abstract:

Modification of nickel sulfide cocatalysts is considered to be a promising approach for efficient enhancement of the photocatalytic hydrogen production performance of g-C3N4. Providing more NiS cocatalyst to function as active sites of g-C3N4 is still highly desirable. To realize this goal, in this work, a facile sulfur-mediated photodeposition approach was developed. Specifically, photogenerated electrons excited by visible light reduce the S molecules absorbed on g-C3N4 surface to S2-, and subsequently NiS cocatalyst is formed in situ on the g-C3N4 surface by a combination of Ni2+ and S2- due to their small solubility product constant (Ksp = 3.2 × 10-19). This approach has several advantages. The NiS cocatalyst is clearly in situ deposited on the photogenerated electron transfer sites of g-C3N4, and thus provides more active sites for H2 production. In addition, this method utilizes solar energy with mild reaction conditions at room temperature. Consequently, the synthesized NiS/g-C3N4 photocatalyst achieves excellent hydrogen generation performance with the performance of the optimal sample (244 μmol h-1 g-1) close to that of 1 wt% Pt/g-C3N4 (316 μmol h-1 g-1, a well-known excellent photocatalyst). More importantly, the present sulfur-mediated photodeposition route is versatile and facile and can be used to deposit various metal sulfides such as CoSx, CuSx and AgSx on the g-C3N4 surface, and all the resulting metal sulfide-modified g-C3N4 photocatalysts exhibit improved H2-production performance. Our study offers a novel insight for the synthesis of high-efficiency photocatalysts.

Key words: g-C3N4, NiS, Co-catalyst, Sulfur-mediated photodeposition, H2, Photocatalysis