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

Abstract

The hydrogen evolution reaction (HER) is significantly influenced by the evolved H2 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 in situ on carbon cloth [denoted as (NiCo)­S2@MoS2/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 MoS2 concentration. Owing to the synergistic effect of metal Ni and Co and the interaction of the (NiCo)­S2@MoS2 heterostructure, (NiCo)­S2@MoS2/CC-2 delivers a relatively low overpotential of 74 mV at a current density of 10 mA cm–2 and displays a small Tafel slope of 54 mV dec–1 for HER catalysis, surpassing that of the recently reported MoS2-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.

A new synthesis approach of hierarchical MoS2 nanoflakes toward hydrogen evolution in both acidic and alkaline media

“…The ultrasonic cavitation phenomena in liquid at the moment of ultrasonic emission will generate a large number of tiny bubbles (the so-called “bubble effect”), and subsequently the bubbles break up in an instant to produce local high temperature and pressure for the nucleation and growth of the crystal nucleus. 20–23 This process will also generate a mechanical stirring effect, preventing the growth and recombination of the crystal nucleus.…”

Fe Engineering on Ru Nanosheets for Enhanced Hydrogen Evolution in pH-Universal Media

“…Ruthenium (Ru) is the most inexpensive element among noble metals. , Moreover, Ru possesses a comparable binding for hydrogen (65 kcal mol –1 ) as Pt (62 kcal mol –1 ). − Prior investigations suggest that engineering on size, dimension, and composition are effective to optimize the Ru property, for expediting hydrogen generation. − Volmer and Heyrovsky processes are the general rate-determining steps for nonacidic hydrogen production, which typically depend on the ability of water dissociation and hydrogen binding, respectively . Henceforth, ration design is desirable to reach high-performance Ru-based HER catalysts.…”

NiS2-Coated Carbon Fiber Paper Decorated with MoS2 Nanosheets for Hydrogen Evolution

“…Recently, the over consumption of fossil fuels has resulted in global energy crisis and serious environmental pollution. − In order to solve the problems, it is necessary to develop clean and renewable energy. At present, the existing clean energy such as hydrogen and solar energy and so on has been widely concerned. , Hydrogen, as a kind of sustainable and clean energy, has been regarded as an alternative to fossil fuels. , There are many ways to produce hydrogen.…”