Oriented facet heterojunctions on CdS nanowires with high photoactivity and photostability for water splitting

The construction of a heterojunction structure with close contact and good light absorption capability is crucial to achieve the good photocatalytic H-2 evolution performance. The heterostructure of photocatalyst with different orientations has proved to be an efficient strategy for photocatalytic water splitting. Herein, an oriented facet heterojunction (OFH) photocatalyst is reasonably designed with ZnIn2S4 nanosheets (ZIS NSs) and CdS nanowire (NW), in which strained interface between the two materials leads to high separation efficiency of electron-cavity. This heterostructure achieves photocatalytic H2 activity of 3072 mu mot h(-1) g(-1) with excellent long-term stability ( > 30 h) under simulated solar light. By considering the interactions between atoms and electrons in the interface region, our density functional theory (DFT) calculation reveals the strong interfacial coupling between the ZnIn2S4 tip and the CdS stem. These findings open up a new platform of OFH-engineered nano-catalysts for more powerful and more efficient solar energy utilization and environmental applications.