Modulating the Binding Strength of Multiple Intermediates by Few‐Layer Fullerene Network Electron Buffer for Alkaline Hydrogen Evolution

The reaction kinetics for electrochemical hydrogen evolution reaction (HER) in an alkaline medium is more sluggish than in acid because it involves extraordinary adsorption and desorption of multiple oxygenated intermediates. Herein, by using covalently bonded 2D fullerene C₆₀ network (abbreviated 2D-C₆₀) as a unique support of Ru nanoparticles (NPs), the binding strengths of the key intermediates in the alkaline HER process are successfully modulated owing to the electron buffering effect of 2D-C₆₀, which can dynamically buffer the change of charge density on metal active sites resulted from the adsorption and desorption of intermediates. The as-prepared Ru NPs/2D-C₆₀ catalyst exhibits a low overpotential of 24 mV at 10 mA cm^-1 and eight times higher intrinsic activity than Ru NPs toward the alkaline HER. The kinetics studies and theoretical calculations reveal that, thanks to the reversible charge transfer among 2D-C₆₀, metal, and intermediates during the HER process, the binding strengths of both H and OH species on the Ru surface are weakened, affording an accelerated HER kinetics process and improved HER activity.