Facile Constructionof CoSSe/g‑C₃N₄ Schottky Junction forEfficient Photocatalytic H₂ Evolution

Abstract

In this study, the CoSSe cocatalyst was synthesized by using a sequential hydrothermal-calcination strategy, and the g-C₃N₄ (CN) photocatalyst was obtained through high-temperature thermal polycondensation. Subsequently, CoSSe/CN composites with varying amounts of CoSSe were fabricated using a solution-based physical drying method. The study demonstrates that the photocatalytic H₂ evolution rate (r_H2) of 30 wt % CoSSe/CN can reach 9675 μmol g^–1 h^–1, showing a boost of 93 times compared to that of bare CN. This improvement stems largely from the Schottky junction created at the interface between CoSSe and CN, which significantly enhances charge separation efficiency. In this structure, CoSSe demonstrates a charge storage capability by providing temporary storage sites for electrons (e^–). Moreover, the CoSSe cocatalyst introduces more reactive sites and reduces the activation energy required for H₂ production, leading to efficient and stable H₂ production. This study underscores the highly prospective application value of selenosulfides in terms of the photocatalytic H₂ production field.