Few-layered ReS₂ nanosheets grown on graphene as electrocatalyst for hydrogen evolution reaction

Few-layered ReS₂ two-dimensional (2D) semiconductor nanosheets directly nucleated and grown on reduced graphene oxide (RGO) were synthesized through a facile hydrothermal method. Compared with bare ReS₂, the ReS₂/RGO hybrid delivers much better electrocatalytic activity for hydrogen evolution reaction (HER) in acidic media. It exhibits a lower Tafel slope of 107.4 mV·dec⁻¹ and a larger current density of − 5.2 mA·cm⁻² at − 250 mV (vs. RHE), compared with ReS₂ (152.7 mV·dec⁻¹, − 3.1 mA·cm⁻²). The ReS₂/RGO hybrid has a unique architecture constructed by highly conductive and porous RGO internetworks, which guarantees easy electrolyte infiltration and efficient charge transfer and provides sufficient active edge sites, resulting in enhanced HER performance. The present synthesis approach can be extended to synthesize other 2D-semiconductor-based composites for energy storage and catalytic devices.