Active sites formed on InVO4/Co3O4 S‐scheme heterostructure for photocatalytic hydrogen production

The reasonable design of S-scheme heterojunction to avoid unwanted charge transfer paths in hybrid semiconductors is considered to be an attractive method to obtain efficient photocatalytic hydrogen evolution activity. The photocatalytic hydrogen evolution performance of the system was improved by loading ultra-thin InVO4 nanosheets on the surface of hollow cube Co3O4 to form an S-scheme heterojunction. Benefiting from the unique nano-cage structure derived from the zeolitic imidazolate frameworks (ZIF) series, it not only provides a good carrier for activating and stabilizing InVO4 nanosheets but also effectively avoids the masking of active sites caused by self-agglomeration, which is more conducive to the exposure of more active sites. The optimized InVO4/Co3O4 has a more competitive H2 production, which is undoubtedly due to the construction of S-scheme heterojunctions and unique spatial structure that facilitates the spatial separation of photoexcited charges. It is further confirmed that the photogenerated carrier transfer follows the S-scheme mechanism by in-situ irradiation XPS test.