Harnessing Hydrogen Spillover by Lattice Strain for Enhanced Photocatalytic Hydrogen Evolution of ZnIn2S4

Hydrogen spillover has been believed to play an essential role in the reaction path in photocatalysis, yet its rational regulation remains a considerable challenge for the design of highly efficient photocatalysts. Herein, hydrogen spillover can be well regulated at ZnIn2S4 with surface decorated by cubic α-MoC1–x quantum dots (QDs) with different lattice strain (ZIS/QDs). With the increasing lattice strain of α-MoC1–x, the composite shows first increased and then decreased photocatalytic hydrogen evolution (PHE). Spectroscopic characterizations and calculation analysis indicate that PHE performance of ZIS/QDs is highly corelated with hydrogen spillover rather than charge transfer process. Further systematic investigations suggest that compressive lattice strain uplifts the Fermi level of α-MoC1–x and optimizes the interfacial spillover barrier between α-MoC1–x and ZnIn2S4, achieving well-manipulated hydrogen spillover and enhanced PHE performance. This work demonstrates a general design from the perspective of lattice strain to harness hydrogen spillover effect in heterogeneous interface for hydrogen generation.