Synergistic Interfacial Reconstruction and Surface Polarization in a Compact ZnIn2S4–CdIn2S4 Heterojunction for Enhanced Photocatalytic H2O2 Production

Constructing compact heterostructures proves to be a productive approach to achieving charge separation and photocatalytic efficiency. However, the stochastic nature of the interface orientation and lattice mismatch in an apparently compact heterostructure often misleads carrier migration and molecular activation in the interface. Here, the S defect-enriched ZnIn2S4–CdIn2S4 compact heterojunctions were prepared for photocatalytic H2O2 production. Notably, this study utilized only water and oxygen as raw materials without additional reagents, achieving a H2O2 yield of 843.02 μmol g–1 h–1. A plethora of experimental results substantiate that the existence of internal stress initiates a restructuring of the interwoven interface and surface misfit dislocation networks. On the one hand, interfacial coherency establishes a central carrier transmission channel to significantly mitigate the charge transfer resistance caused by vacancies. Furthermore, interfacial coherency induces a surface structural reconstruction to enhance the polarization and adsorption of O2, as well as reduce the reaction activation energy. Our findings offer valuable insights into the underlying mechanism governing surface activity through heterojunctions and uncover the relationship between the compacted interface and vacancies.