Electrodeposition of Ni/Ni(OH)₂ Catalytic Films for the Hydrogen Evolution Reaction Produced by using Cyclic Voltammetry

Abstract

Effective artificial photosynthesis to produce hydrogen from water requires active, earth‐abundant, and low‐cost electrocatalysts. In this Communication, we present a novel electrodeposition method to produce Ni/Ni(OH)2 catalytic films in situ on conductive surfaces. The new method involves two cycles of cyclic voltammetry, and produces a catalytic film with a surface morphology consisting of a monolayer of firmly packed walnut‐shaped particles. It has superior catalytic activity compared to catalysts produced through traditional electrodeposition methods under constant current density. The method is a simpler and more cost‐effective way to fabricate highly effective hydrogen evolution electrocatalysts, creating large numbers of Ni(OH)2/Ni interfaces that shift the catalyst's performance significantly towards that of platinum.

Understanding the Enhancement of Electrocatalytic Activity toward Hydrogen Evolution in Alkaline Water Splitting by Anodically Formed Oxides on Ni and C‐containing Ni

“…This indicates that VA cycling led to the enhancement of electrocatalytic activity toward HER. The rise of cathodic current after VA cycling was earlier reported for Ni [32–34] and in particular for Ni/rGO [33,34] …”

“…Oxides/hydroxides undergo reduction under conditions of hydrogen evolution, therefore, they may act both by themselves as well as by their reduction products. Species of Ni(II) have been recognised for their electroactivity, [27–32] therefore, the high‐valence oxides might act as a source of these species. If so, then the enhanced efficiency of the oxides might be ascribed to their longer durability.…”

“…The high and sustained electrocatalytic activity was reported for Ni oxides/hydroxides which were deposited on porous substrates, such as Ni foam [27,30] or carbon cloth [28] . The activity of Ni can also be enhanced by voltammetric cycling on smooth samples, [32–35] and additionally by incorporation of carbon, mainly graphene and/or reduced graphene oxide (rGO) [33,34,43,35–42] …”

Electrodeposition of Nickel Nanoparticles for the Alkaline Hydrogen Evolution Reaction: Correlating Electrocatalytic Behavior and Chemical Composition

“…The electrochemical deposition method is considered one of the best choices, because direct formation of Ni metal/oxides mixtures can be realized and controlled easily . It is also an effective method to prepare thin‐film‐ and particle‐type catalysts with high surface areas . However, the catalytic activity and stability of electrodeposited Ni metal/oxides has not yet been investigated in detail by employing X‐ray photoelectron spectroscopy (XPS) to identify the chemical composition and the electronic structure.…”

Layered transition-metal hydroxides for alkaline hydrogen evolution reaction

“…Electrodeposition is a method with simple experimental setup as well as easily-controllable synthesis conditions. To compare two typical eletrodeposition methods of potential controlled and current controlled, Ofoli et al [110] compared CV and constant current (CC) method to deposit Ni films on fluorine-doped tin oxide (FTO)-coated glass. After CV method, the Ni film with a monolayer of firmly packed walnut-shaped particles covered with larger area of Ni(OH)2 exhibited higher HER activity than that of CC method.…”