Anionic Engineering of ReS2-Re2O7-Ni(OH)2/NF Heterostructure for Enhanced Alkaline Hydrogen Evolution

Abstract

Rhenium disulfide (ReS₂) has garnered increasing attention in the field of electrocatalysis as a highly promising catalyst for hydrogen evolution reaction (HER), whereas regulating the in-plane catalytic activity and electrical conductivity of ReS₂ remains a challenge. Herein, self-supported ReS₂-Re₂O₇-Ni(OH)₂ nanoelectrodes with high conductivity were grown on nickel foam through a mild electrodeposition method combined with an anion engineering strategy. Density functional theory (DFT) calculations reveal the moderate adsorption of the reaction intermediate H on the Re site, while current density simulations indicate that the ReS₂-Re₂O₇-Ni(OH)₂/NF material exhibits higher conductivity and a uniform current density distribution. As a consequence, the optimized ReS₂-Re₂O₇-Ni(OH)₂/NF material demonstrates excellent HER activity and long-term stability in alkaline media (1 M KOH), achieving a low overpotential of 83 mV versus RHE at a current density of 10 mA cm⁻², a Tafel slope of 77 mV dec⁻¹, and maintains long-term stability of 72 h. The strategy of anion engineering offers a new perspective in the design and development of highly efficient electrocatalysts for energy conversion and storage applications.