Optimizing the hydrogen adsorption strength on interfacial Ru sites with WN for high-efficiency hydrogen evolution

Abstract

As a member of the platinum group metals, Ru has been considered as an ideal substitute for Pt in the hydrogen evolution reaction (HER) owing to its superior hydrolytic dissociation ability. However, the excessively strong binding energy of Ru–H leads to a sluggish hydrogen desorption process on Ru sites, which hinders its catalytic activity during the HER process. To address this issue, tungsten nitride (WN) with Pt-like electronic properties was used as a supporting material to optimize the interfacial Ru–H binding energy. Our theoretical and experimental results demonstrated that the interfacial Ru–H binding energy can be greatly optimized by tuning the charge of Ru. As a consequence, we designed WN supported Ru nanoparticles on a carbon cloth (Ru NP-WN/CC), which exhibited a low overpotential of 9 mV at a current density of 10 mA cm⁻² with a small Tafel slope of 29 mV dec⁻¹. This work provides insights into the development of supported Ru-based nanomaterials for highly active electrocatalysts.