Kinetic Study of Electrochemical Deposition of Nickel from Chloride Baths in the Presence of Saccharin

Nickel is an essential engineering material and electrodeposited Ni has been widely used in many fields to improve surface finishing, corrosion resistance and wear properties. The kinetics of electrochemical deposition of nickel from chloride baths in the presence and absence of saccharin on the copper substrate was investigated by applying cyclic voltammetry and chronoamperometry measurements. Our results showed that the kinetics of electrochemical deposition of nickel on the copper substrate was under diffusion control. In addition, in the presence of saccharin, the cathodic current peak decreased and the cathodic potential shifted to the more negative potentials. Nucleation and growth mechanisms also changed from instantaneous to progressive. Characteristics of nanocrystalline nickel coatings were studied by X-ray diffractometry (XRD) and field emission scanning electron microscopy (FESEM). XRD patterns showed the decrease of grain size in the presence of saccharin. FESEM images showed that the microstructure is modified and the morphology changes from cauliflower like to spherical in the presence of saccharin.