Boosting Electrocatalytic Activity of Ru for Acidic Hydrogen Evolution through Hydrogen Spillover Strategy

Pristine Ru generally shows unsatisfying activity for the electrocatalytic hydrogen evolution reaction (HER). How to activate its HER activity through facile methodologies is very challenging. Recently, metal-supported electrocatalysts integrating metals with efficient hydrogen adsorption and supports with facile hydrogen desorption delivered a high HER performance through a metal-to-support hydrogen spillover process, where the small metal–support work function difference (ΔΦ) was identified as the criterion for the successful interfacial hydrogen spillover. Herein, we demonstrate that a hydrogen spillover strategy significantly boosts the HER activity of Ru by depositing a Ru1Fe1 alloy on CoP (Ru1Fe1/CoP) with a small ΔΦ of 0.05 eV. Experimentally, Ru1Fe1/CoP (0.7 wt % Ru loading) delivered a high Ru utilization activity of 139.8 A/mgRu and a long-term durability in acid. Mechanism investigations authenticated that the small ΔΦ guaranteed the interfacial hydrogen spillover from Ru1Fe1 with efficient hydrogen adsorption to CoP with facile hydrogen desorption and thereafter boosted the HER activity of Ru.