Nucleation and growth of copper particles on Pt and Pt/poly-3-methylthiophene modified electrode in presence of Cl− complexing agent

The kinetics of electrochemical deposition of copper particles from Cu2+ solution on platinum and poly-3-methylthiophene modified platinum electrode was studied in potentiostatic conditions in presence of Cl− anions. The complex behavior of current transients suggests that the deposition process involves several stages with different kinetics. Results obtained on platinum show that after an initial adsorption process, the copper deposition is accomplished through two different models: a three-dimensional nucleation and growth under diffusive control (3DPD model) and a progressive nucleation and two-dimensional growth (2DP model). The analysis of current transients recorded on platinum poly-3-methylthiophene modified electrode (Pt/PMT) shows a very different behavior. On Pt modified electrode a process of growth related to a semi-infinite diffusion to a planar surface was accompanied by two different mechanisms of nucleation and growth: a three-dimensional nucleation and growth with no diffusive control (3DP model) and an instantaneous nucleation with two-dimensional growth (2DP model).