Synergistic enhancement of visible-light-driven hydrogen production on graphitic carbon nitride: dual-active-site engineering with carbon vacancies-anchored Au single stoms and quantum dots.

The synergetic catalysis of metal single atoms and their nanoclusters is one of the innovative strategies to enhance the visible light driven H production of graphitic carbon nitride (g-CN, CN). However, existing methods for co-anchoring metal single atoms and their clusters onto CN remain overly cumbersome. In this study, a carbon vacancies trap strategy is proposed to precisely control the type and location of Au species formation on CN. The resulting novel dual-active-site photocatalyst (Au/CCN) achieves a breakthrough in H production activity, with a rate of 1318.8 μmol h g under visible light irradiation. Various characterization techniques have been used to demonstrate that the catalyst optimizes the absorption of visible light and band structure, and significantly improves the efficiency of charge separation and transport. Complementary density functional theory (DFT) calculations further confirm that Au/CCN optimizes carrier dynamics. Additionally, a synergistic effect between proton transport and electron transfer is observed between Au single atoms and quantum dots, while the H spillover phenomenon is effectively inhibited. Overall, this study provides valuable insights and a critical reference for the design and development of dual-active-site photocatalytic materials for H production.