Modulating the Electronic Structure by Ruthenium Doping Endows Cobalt Phosphide Nanowires with Enhanced Alkaline Hydrogen Evolution Activity

Searching for a low-cost and effective transition metal electrocatalyst to substitute for the Pt-based catalysts used in the hydrogen evolution reaction (HER) is a significant but challenging undertaking. Here, electronic structure engineering is adopted to develop high-efficiency HER electrocatalysts over a self-supported ruthenium-doped cobalt phosphide nanowire array on carbon cloth (RuCoP/CC) as a flexible cathode. The obtained catalyst exhibits remarkable HER performance, which demands an overpotential of 58 mV to afford 10 mA cm(-2) in 1.0 M KOH and maintains the performance over 100 h with a slight decay at the current density of 50 mA cm(-2) and 100 mA cm(-2). Density functional theory calculations and various characterization analyses demonstrate that strong electron interaction among different components, optimal hydrogen adsorption free energy, and high electrical conductivity due to the doping of Ru are the vital factors for enormously improving the HER activity. This work opens a facile and scalable path for designing HER electrocatalysts with high performance and long-term stability.