Heterojunction photocatalysts have shown their immense capability in enhancing photogenerated charge carrier separation. Yet, the intrinsic scarcity of active sites in semiconductor components of heterojunction photocatalysts limits their potential for photocatalysis being used in practical applications. Herein, we employ a non-noble metal cocatalyst (i.e., NiS) for modulating a S-scheme heterojunction photocatalyst consisting of Cd₃(C₃N₃S₃)₂ (CdCNS) and CdS. It is revealed that the formation of the CdCNS/CdS S-scheme heterojunction can enable optimal photogenerated charge carrier utilization efficiency and optimized redox capability. More importantly, the meticulous loading of NiS can play multiple roles in enhancing the photocatalytic performance of the CdCNS/CdS photocatalyst, including endowing it with abundant surface-active sites and acting as a photogenerated electron acceptor. As a result, the optimized NiS-loaded CdCNS/CdS attains an excellent hydrogen production rate of 38.17 mmol g⁻¹ h⁻¹, to reach a quantum efficiency of 29.02% at 420 nm. The results reported in this work provide an interesting insight into the important roles of surface-active site modulation in optimizing photocatalytic performances.

中文翻译：

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S 型异质结的表面活性位点调制以实现卓越的光催化性能

异质结光催化剂已显示出其在增强光生载流子分离方面的巨大能力。然而，异质结光催化剂的半导体组件中活性位点的固有稀缺性限制了它们在实际应用中使用光催化的潜力。在此，我们采用非贵金属助催化剂（即NiS）调制由 Cd ₃ (C ₃ N ₃ S ₃ ) _{2组成的 S 型异质结光催化剂}(CdCNS) 和 CdS。结果表明，CdCNS/CdS S 型异质结的形成可以实现最佳的光生载流子利用效率和优化的氧化还原能力。更重要的是，NiS 的精细负载可以在提高 CdCNS/CdS 光催化剂的光催化性能方面发挥多种作用，包括赋予其丰富的表面活性位点和充当光生电子受体。结果，优化的载有 NiS 的 CdCNS/CdS 实现了 38.17 mmol g ⁻¹ h ⁻¹的优异产氢率，在 420 nm 处达到 29.02% 的量子效率。这项工作中报告的结果提供了对表面活性位点调制在优化光催化性能中的重要作用的有趣见解。