Recently, the step-scheme (S-scheme) heterojunction has gained significant attention due to its effective electron-hole separation and strong redox capabilities. However, reports on covalent organic framework (COF)-based S-scheme heterojunctions for photocatalytic RhB degradation remain limited. In this study, an S-scheme ZnIn₂S₄@COF-5 heterojunction photocatalyst was successfully synthesized by growing COF-5 on the surface of ZnIn₂S₄ nanosheets, achieving efficient RhB degradation. Using 30 mg of ZnIn₂S₄@COF-5, we degraded 50 mL of an 80×10^-6 RhB solution, achieving a 97% removal rate within 90 min. The photocatalytic performance of the ZnIn₂S₄@COF-5 S-scheme heterojunction was approximately 1.7 times higher than that of ZnIn₂S₄ and 1.6 times higher than COF-5 alone. Compared to the other reported COF-based S-scheme heterojunctions and commercial photocatalysts, this ZnIn₂S₄@COF-5 photocatalyst exhibited superior photocatalytic performance. The S-scheme charge transfer mechanism of the ZnIn₂S₄@COF-5 heterojunction was elucidated through in situ irradiated XPS. Experimental results demonstrate that this rational design not only facilitates the effective separation of photogenerated electrons and holes, but also provides a large surface area and abundant active sites for efficient RhB degradation.

中文翻译：

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S-Scheme ZnIn2S4@COF-5 光催化剂原位辐照 XPS 研究增强光催化降解 RhB


近年来，阶梯式异质结因其有效的电子-空穴分离和强大的氧化还原能力而受到广泛关注。然而，关于基于共价有机框架 （COF） 的 S 型异质结用于光催化 RhB 降解的报道仍然有限。在本研究中，通过在 ZnIn₂S₄ 纳米片表面生长 COF-5，成功合成了 S 型 ZnIn₂S₄@COF-5 异质结光催化剂，实现了高效的 RhB 降解。使用 30 mg ZnIn₂S₄@COF-5，我们降解了 50 mL 的 80×^10-6 RhB 溶液，在 90 分钟内达到 97% 的去除率。ZnIn₂S₄@COF-5 S 型异质结的光催化性能比 ZnIn₂S₄ 高约 1.7 倍，比单独使用 COF-5 高 1.6 倍。与其他已报道的基于 COF 的 S 型异质结和商用光催化剂相比，这种 ZnIn₂S₄@COF-5 光催化剂表现出优异的光催化性能。通过原位辐照 XPS 阐明了 ZnIn₂S₄@COF-5 异质结的 S 型电荷转移机制。实验结果表明，这种合理的设计不仅有利于光生电子和空穴的有效分离，而且为高效的 RhB 降解提供了较大的表面积和丰富的活性位点。