Electrodeposition and electrocatalytic study of Ni-W alloy coating

Abstract

Electrocatalytically active Ni-W alloy coatings have been developed through compositionally versatile electrodeposition method on copper substrate from tri-sodium citrate bath, using glycerol as the additive. The deposition conditions have been optimized for peak performance of their electrocatalytic behavior, like hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in 1M KOH. Corrosion behaviors of the coatings have also been tested under study conditions of electrocatalysis. Electrocatalytic behaviors were tested by cyclic voltammetry (CV) and chronopotentiometry techniques. Experimental results demonstrated that Ni-W alloy coatings, deposited at low and high current densities (c. d.) were showing superior performance for OER and HER, respectively. Better electrocatalytic activity for HER with increase of deposition c. d. was attributed by the unique phase structure, surface morphology and chemical composition of the coatings, confirmed by XRD, SEM and EDX analysis. The dependency of coating thickness and hardness on HER and OER were analyzed, and results are discussed. � (2015) Trans Tech Publications, Switzerland.