Gel-assisted synthesis of CIZS for visible-light photocatalytic reduction reaction

• DOI: 10.1016/j.cej.2021.132364
• Publication Date: 2021-09-09T16:01:41Z
• Authors: Zhengzheng Xie; Wang Xu; Fan Fang; Kai Zhang; Xu Yu; Kun Chang
• Keywords: Visible spectrum; Band bending

Abstract ZnS-CuInS2 (CIZS) solid solution is synthesized via a chitosan gel-assisted method. The bandgap of the obtained CIZS semiconductor is 1.68 eV, and the position of the flat potential is 0.86 eV. When Ru is selected as the cocatalyst, the photocatalytic hydrogen evolution rate of CIZS@Ru reaches 4.86 mmol g−1h−1 under visible-light (λ＞420 nm) radiation, and it presents good stability. Besides, CIZS@Ru also shows good CO2 reducibility, where the product contains hydrogen, methane, and a small amount of formate. The photoelectrochemical tests also suggest that Ru is the optimum cocatalyst compared with Rh, Pt and Ni. Meanwhile, the internal mechanism of photogenerated charge transfer between semiconductors and cocatalyst has been revealed by the band bending concept. This work provides a novel and facile strategy to fabricate p-type CIZS semiconductor with high visible-light photocatalytic reduction performance.