ZnInGaS4 heterojunction with sulfide vacancies for efficient solar-light photocatalytic water splitting and Cr(VI) reduction

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2023-01, Vol.452, p.139386, Article 139386
• Main Authors: Peng, Hao, Du, Yaohan, Yong, Jiahuan, Huang, Congying, Zheng, Xiaogang, Wen, Jing
• Format: Article
• Language: English
• Subjects: Cr (VI) reduction; Solar light; Sulfide vacancy; Water splitting; ZnInGaS4
• ISSN: 1385-8947; 1873-3212
• DOI: 10.1016/j.cej.2022.139386

•S-defected ZnInGaS4 was prepared via the microwave hydrothermal route.•ZnInGaS4 exhibits the excellent solar light driven H2 evolution.•ZnInGaS4 presents the superior photocatalytic activity for Cr(VI) reduction.•Tight interface between ZnIn2S4 and ZnGa2S4 favors the rapid charge transfer. ZnInGaS4 heterojunction with S vacancies was prepared via the microwave hydrothermal route to boost the solar-light photocatalytic activity for water splitting and Cr (VI) reduction. The tight interface between ZnIn2S4 and ZnGa2S4 favors the rapid separation and transfer of photo-induced electron-hole pairs, and the narrowed band gap is suitable for visible-light harvesting. In addition, S vacancies serve as the adsorption sites and photons capture, leading to the efficient solar utilization. Compared with ZnIn2S4 (0.94 mmol g-1h−1) and ZnGa2S4 (0.33 mmol g-1h−1), the optimal ZnInGaS4 with a In/Ga molar ratio of 1:1 exhibits the better H2 evolution rate (4.47 mmol g-1h−1) and the apparent quantum yield of 20.16 % at wavelength of 400 nm. The removal efficiency of ZnInGaS4 for solar-light driven Cr (VI) reduction is 99.46 % within 140 min, which is higher than ZnIn2S4 (93.14 %) and ZnGa2S4 (89.31 %). The photo-corrosion induces to the deactivation of ZnGa2S4 for solar-light driven H2 evolution and Cr (VI) reduction after five cycles.