CuInSe2 nanoplatelets decorated CdS nanosheets as 2D-2D S-scheme photocatalyst for photocatalytic H2 generation coupled with benzyl alcohol oxidation and microplastic degradation

In this work, a novel 2D layered heterojunction for various photocatalytic reactions is constructed by hybridizing CdS nanosheets and CuInSe2 nanoplatelets. By adjusting CuInSe2 content, the CdS-16% CuInSe2 sample displays a visible-light-induced H2 production rate of 4382 μmol g−1 h−1, approximately 7.5 times higher than pristine CdS. Furthermore, CdS-16% CuInSe2 demonstrates exceptional photocatalytic activity in H2 evolution simultaneous benzyl alcohol (BA) oxidation and polyethylene terephthalate (PET) degradation. The superior photocatalytic activity is ascribed to the unique S-scheme heterojunction and 2D-2D CdS–CuInSe2 layered heterostructures that effectively separate photoinduced charge carriers and provide appropriate interfacial band structures. The photocatalytic mechanism is thoroughly examined through experiments and density functional theory calculations. This work offers a valuable platform to develop innovative layered photocatalysts that are highly effective for a wide range of photocatalytic reactions.