Hierarchical Coralline-like (NiCo)S2@MoS2 Nanowire Arrays to Accelerate H2 Release for an Efficient Hydrogen Evolution Reaction

The hydrogen evolution reaction (HER) is significantly influenced by the evolved H2bubble diffusion rate on the surface of the electrode, which involves the blocking and release of the active site at the catalytic interface. Rational design ofnanostructured catalysts could not only sharply enhance thespecific surface area but also provide large amounts of channels forgas release. Herein, NiCo-nanowire-derived multimetal chalcoge-nides grownin situon carbon cloth [denoted as (NiCo)S2@MoS2/CC] are presented by serial hydrothermal methods. The obtainedhierarchical nanowire array architecture affords abundant surface-active sites and is conducive to permeate electrolytes. The surfaceadsorption/desorption behavior of the heterostructure catalyst wasoptimized through regulating MoS2concentration. Owing to the synergistic effect of metal Ni and Co and the interaction of the(NiCo)S2@MoS2heterostructure, (NiCo)S2@MoS2/CC-2 delivers a relatively low overpotential of 74 mV at a current density of 10mA cm-2and displays a small Tafel slope of 54 mV dec-1for HER catalysis, surpassing that of the recently reported MoS2-basedelectrocatalysts. Such a strategy through nanostructure optimization and electron interaction of the heterostructure could improvethe electrocatalytic HER performance for multimetal chalcogenides in an alkaline medium

Automated summary

The authors synthesized a new catalyst material (NiCo)S2@MoS2/CC by serial hydrothermal methods, which exhibits abundant surface-active sites and excellent electrocatalytic performance for the hydrogen evolution reaction in alkaline medium.