In Situ Cascade Growth-Induced Strong Coupling Effect Toward Efficient Photocatalytic Hydrogen Evolution of Res2/Znin2s4

Abstract

Optimizing electron structure of H2-evolution active sites to improve their catalytic efficiency is of great significance to develop efficient photocatalysts. Herein, an in situ cascade growth-induced strong coupling interface between ReS2 and ZnIn2S4 nanolayers was developed to realize the electron structure optimization of S-active sites in ReS2 cocatalyst, which can greatly improve the H2-evolution efficiency of ZnIn2S4 photocatalyst. The in situ cascade growth of ReS2/ZnIn2S4 includes initial formation of ZnIn2S4 nanolayers (ca. 200 oC) and their subsequent surface-induced production of ReS2 (ca. 300-380 oC) in molten system. The resulting ReS2/ZnIn2S4(3wt%) shows a superior H2-production rate, which is ca. 20.6 and 2.0 times higher than that of ZnIn2S4 and ReS2-ZnIn2S4 (physical mixing), respectively. Besides the promoting transfer of photogenerated carriers, the cascade growth-induced strong coupling effect in the ReS2/ZnIn2S4 can induce the construction of electron-deficient Sδ+ site of ReS2, causing the optimized binding strength of S-H bond and excellent H2-evolution activity.

Keywords: Photocatalysis, Hydrogen evolution, Cocatalyst, ReS2, ZnIn2S4