Electrodeposition and Electrocatalytic Study of Ni–Co Alloy Coatings

The present work focusses on the fabrication of new Ni–Co electrolyte for the development of Ni–Co electrocatalysts for water splitting application. All the Ni–Co alloy coatings were deposited from an acid sulphate bath and their electrocatalytic activity was tested in 1 M KOH. The Ni–Co alloys developed at range of current density from 3.0 to 6.0 A dm^–2 were found to be good electrode materials for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), as demonstrated by cyclic voltammetry (CV) and chronopotentiometry (CP) methods. The Ni–Co alloy deposits which are catalytically active for HER are found to be inactive for OER and vice versa. The change in surface appearance, composition, and the phase structure of all developed coatings were analysed using instrumental techniques like scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD), respectively.