The morphology of different metals electrodeposited onto polyaniline films

Abstract

The process of electrochemical deposition/dissolution and the morphology of obtained deposits of cadmium and copper onto polyaniline films of different thickness have been investigated by linear sweep voltammetry, the potentiostatic pulse technique and in situ microscopic monitoring. It was shown that both metals can be deposited onto polyaniline films, although cadmium deposits at the potentials where the polymer is non-conductive while copper deposits at the potentials where the polyaniline is partially oxidized (conductive). Cadmium was found to deposit only into the open pores of the polymer onto glassy carbon substrate at particular places of the polyaniline surface, so that a compact layer of cadmium cannot be obtained. It was also shown that the whole amount of deposited cadmium cannot be dissolved at the potential of “normal” dissolution of cadmium, and the rest of the deposit dissolves at potentials of polyaniline oxidation. In contrast, a compact layer of copper of a desired thickness can readily be deposited onto a polyaniline film surface. It was suggested that in situ microscopic monitoring of the morphology of deposits of metals depositing onto reduced (non-conductive) polymer films can be used as a method for determination of the porosity of polymer films.