ANALYSIS OF THE CURRENT RESPONSE ON THE REVERSE SCAN OF POTENTIAL SWEEP IN ELECTRODEPOSITION

The cathodic current response on the reverse scan in potential sweep (the reverse scan technique) for new-phase formation, especially for the deposition of metals, is analyzed. The technique is a simple and effective method for measuring the kinetic parameters of deposition processes which have reasonably simple diffusion/interfacial electron transfer control kinetics, such as the deposition of cobalt and nickel from the noncomplexing solutions. The effectiveness of the reverse scan technique is based on sweeping to a region where the kinetics is under limiting diffusion control in the predeposition before the measurements. This eliminates the influence of the other processes in electrodeposition, such as nucleation, surface diffusion of adatoms, and the change in surface area, on the current response in the measurement.