AFM imaging of copper stripping/deposition processes in selected electrolytes on boron-doped diamond thin-film electrodes

摘要

Electrochemical atomic force microscopy (EC AFM) studies of copper stripping/deposition processes under potentiostatic control were carried out on boron doped diamond thin-film electrodes in solutions of different ability to form copper complexes. Careful analysis of the electrode surface profiles taken at the potentials switched between oxidative and reductive values reveals the nucleation state and the early stages of complex formation when cations are released from the deposited metal. An unusual increase of the deposit-layer thickness is observed in sulfate- and phosphate-solutions at the positive potentials in contrast to an expected decrease of the surface adlayer thickness accompanying its stripping. The last effect takes place in the case of copper stripping in the presence of nitrates when no complex is formed. Similar behavior is observed on the HOPG electrode used in these studies as a reference surface.