Hydrogen Spillover Modulated by Microenvironment Engineering toward Efficient Photo-Redox Catalysis

Abstract

As a fundamental process in heterogeneous catalysis, hydrogen spillover has garnered increasing attention in the field of photocatalysis. However, the influence of local microenvironment on hydrogen spillover remains elusive, and strategies to deliberately regulate this phenomenon in photo-redox reactions are still in their infancy. Herein, we report the design of W-doped α-MoC1–x quantum dots anchored on a multifunctional graphene support, where the degree of graphene crystallization can be precisely modulated. Our findings reveal that hydrogen spillover can be effectively orchestrated by tailoring the local environment particularly in the presence of free H2O and surface hydroxyl groups, resulting in over a 20-fold enhancement in photocatalytic hydrogen evolution compared to bare ZnIn2S4. Furthermore, an ordered graphene arrangement facilitates continuous hydrogen spillover and maintains hydroxyl dynamic equilibrium, significantly boosting the photocatalytic stability. This work highlights the critical role of mass transfer in photocatalysis. These insights open new avenues for advancing photocatalysis research through microenvironment engineering.