Hollow Nickel Nanochains Coated with Nickel-Iron Hydroxide for Oxygen Evolution

Abstract

The growth of layered double hydroxide (LDH) structures on transition-metal substrates shows great potential for generating highly effective and low-cost water electrolysis catalysts. Herein, nanochains of hollow nickel mesospheres (hNi) synthesized using a template-free reflux method were utilized to develop NiFe-OH. Subsequently, the acid-treated hNi (hNiH) induced the formation of a three-dimensional hierarchical hNiH@NiFe-OH structure possessing an LDH framework. Its growth was regulated by the Fe(II) ions and an optimum chloride ion concentration as determined via the corrosion mechanism. The electrocatalytic activity of the hNiH@NiFe-OH catalyst for the oxygen evolution reaction (OER) was superior to those of references such as hNi, Fe nanowires, hNi@NiFe, and commercial Ir/C catalysts as confirmed by its lowest overpotential value (288 mV at 10 mA cm −2 ) and efficient catalytic kinetics indicated by a Tafel slope of 37 mV dec −1 . Furthermore, this catalyst demonstrated remarkable stability during the OER process, with the overpotential at 10 mA cm −2 showing a marginal increase (16 mV) over 10,000 cycles, whereas a 38 mV increase was observed for Ir/C. These findings successfully demonstrate that the depassivation-assisted in situ NiFe-OH formation using hNiH nanochains is a promising approach for developing highly efficient OER catalysts.

Cobalt–Copper-Embedded Nitrogen-Doped Carbon Nanostructures Derived from Zeolite Imidazolate Frameworks as Electrocatalysts for the Oxygen Reduction Reaction

“…All electrochemical experiments were conducted using a three-electrode system, as in previous studies. 41 A rotating disk electrode (RDE) with an area of 0.071 cm 2 and a rotating-ring disk electrode (RRDE) with a disk area of 0.1256 cm 2 (disk) were used as the working electrode. A Hg/HgO electrode served as the reference electrode, and a Pt wire was used as the counter electrode.…”

Electrospinning construction of a Fe–Ni-based multicomponent hybrid as synergistic electrocatalyst for water electrolysis

“…Nowadays, with the increasing energy crisis and environmental pollution, the innovations for green techniques to reduce the dependence on fossil fuels is an extremely urgent mission. 1–4 Water electrolysis is a green technology to produce hydrogen energy with high calorific value. 5–7 To date, Pt/C and RuO 2 /IrO 2 are state-of-the-art electrocatalysts for water splitting.…”

Co- and V2O3-Modified Ni-Based Nanocatalyst for 5-Hydroxymethylfurfural Electrooxidation

“…With the increasing demand for bulk chemicals and energy in modern society, unrenewable fossil fuels have been exploited and refined on a large scale, accompanied by resource scarcity and environmental pollution. − It is exciting that renewable and eco-friendly biomass can be applied to produce fine chemicals and liquid fuels. , 5-Hydroxymethylfurfural (HMF) is one of the representative platform molecules derived from biomass . 2,5-Furandicarboxylic acid (FDCA), as the oxidation product of HMF, is a significant monomer for synthesizing pharmaceuticals and polyesters. , …”