Construction of Hollow Co3O4@ZnIn2S4 p-n Heterojunctions for Highly Efficient Photocatalytic Hydrogen Production

Photocatalysts derived from semiconductor heterojunctions for water splitting have bright prospects in solar energy conversion. Here, a Co3O4@ZIS p-n heterojunction was successfully created by developing two-dimensional ZnIn2S4 on ZIF-67-derived hollow Co3O4 nanocages, realizing efficient spatial separation of the electron-hole pair. Moreover, the black hollow structure of Co3O4 considerably increases the range of light absorption and the light utilization efficiency of the heterojunction avoids the agglomeration of ZnIn2S4 nanosheets and further improves the hydrogen generation rate of the material. The obtained Co3O4(20) @ZIS showed excellent photocatalytic H-2 activity of 5.38 mmol g(-1)center dot h(-1) under simulated solar light, which was seven times more than that of pure ZnIn2S4. Therefore, these kinds of constructions of hollow p-n heterojunctions have a positive prospect in solar energy conversion fields.

Automated summary

Photocatalysts derived from semiconductor heterojunctions, such as the Co3O4@ZIS p-n heterojunction created in this study, show great potential in solar energy conversion. The Co3O4 hollow structure enhances light absorption and utilization efficiency, while also preventing agglomeration of ZnIn2S4 nanosheets and improving hydrogen generation rate. The Co3O4(20) @ZIS heterojunction exhibits excellent photocatalytic activity, producing hydrogen at a rate seven times higher than pure ZnIn2S4 under simulated solar light. These hollow p-n heterojunctions have promising applications in solar energy conversion.