Boosted Electrochemical Hydrogen Evolution Activity via the Core–Shell Heterostructure of Nickel Sulfide Nanoframe-Supported Layered Rhenium Disulfide

The strategic design of a heterostructure catalyst with a core-shell nanoarchitecture is imperative for enhancing the efficiency of the electrocatalytic hydrogen evolution reaction (HER). Herein, the core-shell catalyst comprising the rhenium disulfide nanosheets was vertically integrated onto a hollow nickel sulfide (NiS@ReS₂) via coprecipitation and hydrothermal treatment. The morphology involves the sulfurization of a nickel-based Prussian blue analogue, effectively mitigating the aggregation of ReS₂ nanosheets and maximizing the exposed active sites. By the synergistic effect of morphological design and heterostructure formation, the overpotential of NiS@ReS₂ is 136 mV at 10 mA cm^-2 in an alkaline electrolyte, and the rapid kinetics is confirmed by the small Tafel slope and low charge transfer resistance during the HER process. Moreover, the electrocatalytic durability of NiS@ReS₂ is elucidated, and the boosted catalytic activity of NiS@ReS₂ is confirmed by density functional theory. This study unveils a promising method for advancing ReS₂-based electrocatalysts with potential implications for producing hydrogen.