Tuning electronic structure via CoS clusters for visual photocatalytic H2 production and mechanism insight

Clusters with this unique atomic arrangement and configuration are highly potential cocatalysts, but designing efficient clusters and clarifying the mechanism of action remains a challenge. Herein, CoS clusters are in-situ grown on CdS nanorods, which leads to the existence of Cd-S-Co bonds. It is found that the Cd-S-Co bonds could induce interfacial charge rearrangements. Theoretical calculations reveal that the charge redistribution of heterostructures at interfaces is conducive to modulating d-band center, reducing thermodynamic energy barriers, and improving carrier separation. The optimized CdS/CoS composite shows a great photocatalytic H2 production rate (65.7 mmol h−1 g−1), such a H2 evolution rate exceeded most reported CdS nanorods photocatalyst. This study provides an experimental and theoretical foundation for the preparation of cluster-semiconductors photocatalytic materials and explores the transfer pathway between clusters and catalysts at the atomic level, and deeply discusses the mechanism of their catalytic performance.