Low-Valent Cation Doping and Leaching to Construct Single-Atom Cu Decorated Cu-Znin2s4 with Multiple Defects for Boosting Photocatalytic H2 Evolution

It is a promising means to enhance photocatalytic activity by ions doping, single-atom decoration, and vacancies introducing, yet a simple approach to realize their simultaneous appearance remains a great challenge hitherto. Herein, an original strategy of low-valent cation doping and leaching is developed to construct a single-atom Cu (Cu10)-decorated and monovalent Cu ion (Cu+)-doped ZnIn2S4 photocatalyst (RCu-ZIS) with multiple defects. Characterizations and theory calculations enclose that the Cu+ dopants and Cu/In/S vacancies clusters induce electron-poor zones, meanwhile, S vacancies and isolated Cu10 result in electron-rich regions, thus forming some local electric field with different states of charge, which can act as electron accepting and donating centers accelerating the transfer and separation of photocarriers. The optimized RCu-ZIS delivers a high visible-light-driven H2 evolution activity of 70.58 mmol·g−1·h−1 with an AQE of 12.24% at 420 nm. This work opens up an all-in-one modification strategy on redounding photocatalytic activity through rational structural fine-tuning.