Interfacial electron modulation for Ru particles on Cu aerogel as an efficient electrocatalyst for hydrogen evolution reaction

Abstract

Interface design for heterogeneous catalysts is essential to modulate the electronic structure, and therefore improve the intrinsic activity. Metal aerogels with hierarchical porous structure are expected to be promising substrates to support heterogenous noble metals to better facilitate the electrocatalytic property. Herein, the Ru–Cu aerogel with the Cu skeleton as support for the heterogeneous anchoring of the Ru particles was synthesized by spontaneous gelation. Due to the electron redistribution at the interface between Cu and Ru, the intrinsic activity for Ru was remarkably reinforced for the hydrogen evolution reaction (HER). Theoretical analysis also suggested the lower Gibbs free energy for hydrogen adsorption (ΔG_H*) of the Ru sites at the interface to promote the adsorption of H*. As a result, the Ru–Cu aerogel presented excellent electrocatalytic activity for the HER with a low overpotential of 42.6 mV to reach the current density of 10 mA cm⁻² and exhibited excellent stability in acid. Therefore, this Ru–Cu aerogel with a unique Ru–Cu interface and three-dimensional structure is proposed as an efficient and robust electrocatalyst for hydrogen production.