Optimizing intrinsic cocatalyst activity and light absorption efficiency for efficient hydrogen evolution of 1D/2D ReS2-CdS photocatalysts via control of ReS2 nanosheet layer growth

Abstract

The visible-light-driven hydrogen evolution is extremely important, but the poor charge transfer capability, a sluggish evolution rate of hydrogen, and severe photo-corrosion make photocatalytic hydrogen evolution impractical. In this study, we present 1D/2D ReS2-CdS hybrid nanorods for photocatalytic hydrogen evolution, comprised of a ReS2 nanosheet layer grown on CdS nanorods. We found that precise control of the contents of the ReS2 nanosheet layer allows for manipulating the electronic structure of Re in the ReS2-CdS hybrid nanorods. The ReS2-CdS hybrid nanorods with optimal ReS2 nanosheet layer content dramatically improve photocatalytic hydrogen evolution activity. Notably, photocatalytic hydrogen evolution activity (64.93 mmol g−1 h−1) of ReS2-CdS hybrid nanorods with ReS2 nanosheet layers (Re/Cd atomic ratio of 0.051) is approximately 136 times higher than that of pure CdS nanorods under visible light irradiation. Furthermore, intimated coupling of the ReS2 nanosheet layer with CdS nanorods reduced the surface trap-site of the CdS nanorods, resulting in enhanced photocatalytic stability. The detailed optical and electrical investigations demonstrate that the optimal ReS2 nanosheet layer contents in the ReS2-CdS hybrid nanorods can provide improved charge transfer capability, catalytic activity, and light absorption efficiency. This study sheds light on the development of photocatalysts for highly efficient photocatalytic hydrogen evolution.