Hierarchical Coralline-like (NiCo)S@MoS Nanowire Arrays to Accelerate H Release for an Efficient Hydrogen Evolution Reaction.

The hydrogen evolution reaction (HER) is significantly influenced by the evolved H bubble diffusion rate on the surface of the electrode, which involves the blocking and release of the active site at the catalytic interface. Rational design of nanostructured catalysts could not only sharply enhance the specific surface area but also provide large amounts of channels for gas release. Herein, NiCo-nanowire-derived multimetal chalcogenides grown on carbon cloth [denoted as (NiCo)S@MoS/CC] are presented by serial hydrothermal methods. The obtained hierarchical nanowire array architecture affords abundant surface-active sites and is conducive to permeate electrolytes. The surface adsorption/desorption behavior of the heterostructure catalyst was optimized through regulating MoS concentration. Owing to the synergistic effect of metal Ni and Co and the interaction of the (NiCo)S@MoS heterostructure, (NiCo)S@MoS/CC-2 delivers a relatively low overpotential of 74 mV at a current density of 10 mA cm and displays a small Tafel slope of 54 mV dec for HER catalysis, surpassing that of the recently reported MoS-based electrocatalysts. Such a strategy through nanostructure optimization and electron interaction of the heterostructure could improve the electrocatalytic HER performance for multimetal chalcogenides in an alkaline medium.