Development of Ni-W alloy coatings and their electrocatalytic activity for water splitting reaction

Abstract

This study reports the electrodeposition of Nickel-Tungsten (Ni-W) alloy coatings and their efficiency as electrode material for water splitting applications. Ni-W alloy coatings were electrodeposited and their electrocatalytic activity towards alkaline water splitting for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in 1 M KOH were studied. Cyclic voltammetry (CV) and chronopotentiometry (CP)techniques were used to quantify their electrocatalytic behaviors. It demonstrated the inverse dependency of electrocatalytic behaviors of coatings towards HER and OER at low and high c.d.'s, respectively. This is attributed to the change in the composition, in terms of Ni and W content of the alloy. The surface features, structural and compositional change of coatings, responsible for improved electrocatalytic activity were examined using Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Energy dispersive X-ray spectroscopy (EDS) techniques. Experiment results revealed that alloy deposit can be used as a potential material for water splitting applications.