Time Dependence of Current during Potentiostatic Growth of Clusters in Diffusion Mode of Electrodeposition

Abstract

The fundamentally new model describes the initial current transients during the growth of clusters in the diffusion mode after instantaneous nucleation. The specific feature of the model is that it is based on the initial hemispherical diffusion of ions from bulk solution to the surface of growing clusters rather than on the period of Cottrell current decay. The subsequent overlapping of diffusion zones is taken into account by multiplying the current by a factor smaller than unity. The factor is equal to the ratio of true diffusion volume to the “extended” volume, which is equal to the overall volume of all diffusion hemispheres ignoring their overlapping. The results calculated by the model appeared to be rather close to those obtained using the conventional Scharifker–Hills–Mostany model, and, thus, confirm the correctness of this model. In this connection, the reasons for its inconsistency with the experimental data on the number of growing clusters remain unclear.