Accelerated Alkaline Hydrogen Evolution on M(OH)x/M-MoPOx (M = Ni, Co, Fe, Mn) Electrocatalysts by Coupling Water Dissociation and Hydrogen Ad-Desorption Steps

Efficient and cheap electrocatalysts for alkaline hydrogen evolution reaction is still a big challenge due to the sluggish water dissociation kinetics as well as poor M–Had energetics. Herein, hydroxide modification and elemental incorporation have been demonstrated to realize a synergistic modulation on a new class of M(OH)x/M-MoPOx catalysts for accelerating water dissociation and hydrogen ad-desorption steps in HER. Theoretical and experimental results disclosed that in situ modification of hydroxide endowed the M(OH)x/M-MoPOx with a strong ability of water dissociation, and meanwhile, oxygen incorporation effectively optimized the M–Had energetics of NiMoP catalyst. Moreover, the interaction between M(OH)x and M-MoPOx components in the M(OH)x/M-MoPOx further enhances their professional skills for catalyzing the two elementary steps in alkaline hydrogen evolution, proving a broad road to efficiently catalyzing hydrogen evolution. In general, the optimized Ni(OH)2/NiMoPOx catalyst exhibits excellent alkaline HER activity and durability, superior to the state-of-the-art Pt/C catalyst when overpotential exceeds 65 mV.