Studies on nucleation and growth kinetics during electrodeposition of nickel thin films

The control of nucleation and growth processes in the initial stages is imperative for uniform and high-quality coatings for various industrial applications. The Ni thin films were electrodeposited on stainless steel substrate, and the effect of applied deposition potential, pH, and concentration of the bath on nucleation and growth kinetics was studied. The 3-dimensional hemispherical mass transfer electro-crystallization model developed by Scharifker and Hills was used to analyze the nucleation and growth kinetics during the initial stages of electrodeposition. The observed physicochemical properties of Ni thin films were correlated with nucleation and growth kinetics during deposition. The X-ray diffraction study confirmed the cubic crystal structure of Ni thin films. The microscopic study revealed the structural evolution from an uneven, cracked structure to uniform, compact structures after tuning the bath pH and other deposition conditions. The present study suggested a mixed 3D instantaneous and progressive nucleation mechanism for Ni thin films under optimised deposition conditions. The results of this study provides a comprehensive theoretical and experimental basis for the controlled growth of electrodeposited Ni thin films.