Efficient separation of charge carriers in the C–S bonded COF@Co9S8 S-scheme heterostructure for enhancing the photocatalytic H2 and H2O2 production

Constructing S-scheme heterojunction is an effective strategy to overcome the limitation of covalent organic frameworks (COFs) materials caused by the rapid recombination of photogenerated carriers in photocatalytic applications. In this work, an organic-inorganic heterojunction hybrid with a puff-like nanoflower sphere structure was successfully fabricated by growing COF on the surface of Co₉S₈. These two components are linked by C–S bonds, which effectively enhances the transfer and separation of charge carriers. Under visible light irradiation, COF@Co₉S₈ can act as an excellent dual-functional catalyst for both photocatalytic hydrogen (H₂) and hydrogen peroxide (H₂O₂) production. The reasonable charge transfer path of the S-scheme heterojunction has been verified through various experiments and theoretical calculation. This research provides a valuable perception for designing organic-inorganic S-scheme heterojunctions based on 2D porous materials for efficient solar energy conversion.