Construction of the VOBiOBr/VSZnIn2S4 heterojunction for photocatalytic hydrogen production and dye removal under simulated sunlight

• Published in: International journal of hydrogen energy 2024-07, Vol.74, p.361-371
• Main Authors: Kuang, Xuanyu, Jin, Xuekun, Chen, Fengjuan, Pan, Anqiang, Duan, Haiming, Wu, Zhaofeng, Cao, Biaobing
• Format: Article
• Language: English
• Subjects: BiOBr; Hydrogen; S-scheme; Vacancy; ZnIn2S4
• ISSN: 0360-3199
• DOI: 10.1016/j.ijhydene.2024.06.088

Semiconductor photocatalysis is a promising method for utilizing solar energy to decompose water and degrade pollutants. However, the limited visible light absorption capacity and high carrier complexation rate hinder the utilization of sunlight for photocatalysts. The study prepared VOBiOBr/VSZnIn2S4 S-scheme heterojunction photocatalysts with sulfur and oxygen vacancies using a two-step solvothermal method. The photocatalyst was then used to simulate sunlight decomposition of water for hydrogen production and degradation of dye wastewater. Characterisation tests revealed that the incorporation of sulfur and oxygen vacancies effectively enhanced the visible light absorption of BiOBr and ZnIn2S4. The construction of S-scheme heterojunction resulted in an improvement in visible light absorption capacity, as well as the promotion of separation and migration of photogenerated carriers. The study demonstrates that VOBiOBr/VSZnIn2S4 exhibits superior hydrogen precipitation and degradation properties compared to BiOBr/ZnIn2S4 without S and O vacancies and VSZnIn2S4 without a heterojunction when subjected to simulated sunlight irradiation. The results of the tests and mechanistic analyses suggest that the synergistic effect of S and O vacancies and heterojunction enhances the photocatalytic performance. This study offers novel perspectives on the production of multifunctional photocatalysts that effectively utilize sunlight. [Display omitted] •Novel dual vacancy VOBiOBr/VSZnIn2S4 heterojunctions were successfully constructed.•VOBiOBr/VSZnIn2S4 photocatalysts demonstrate high photocatalytic activity under simulated sunlight.•The synergistic effect of vacancy and heterojunction greatly enhances the photocatalytic performance of ZnIn2S4.•The built-in electric field at the heterojunction interface can effectively promote carrier separation.