Defect coupled MoSx sites over ZnIn2S4 nanosheets towards efficient H2 evolution

Abstract

The inefficient separation of photoexcited electrons and holes as well as the lack of sufficient reactive sites are considered as the major factors hindering the catalytic activity of the semiconductors. Herein, we report an environmentally friendly and energy-saving method to realize the co-deposition of amorphous MoSx onto ZnIn2S4 (ZIS) nanosheets, through which effectively enhanced performance of H2 generation from water reduction can be achieved. Furtherly, defect-poor ZIS and defect-rich O-doped ZIS (O-ZIS) were taken as the fabrication matrixes respectively, and larger enhancement resulting from MoSx loading over O-ZIS than that over ZIS was achieved, suggesting the synergistic effect that one plus one is greater than two, primarily due to the remarkably enhanced charge carriers separation and more abundant reaction sites for H2 production resulting from the defect engineering coupled surface active sites constructing. Notably, the optimal MoSx/O-ZIS achieved the H2 evolution rate of 15.32 mmol g−1 h−1, which is 17.8 and 8.5 times as that achieved over blank ZIS and O-ZIS, respectively. This work furnishes a facile paradigm that efficient composite materials can be facilely controlled towards boosted solar energy conversion, which significantly simplifies the activity majorization of the component-designed MoSx/ZIS photocatalysts.

Keywords

• Defect engineering
• Surface active sites
• Co-deposition
• Photocatalytic H2 evolution