The present research work studied the polypyrrole electrochemical formation process onto glassycarbon and gold electrodes in the presence of nitrates. During the first cycle of its potentiodynamicgrowth, the oxidation potential was independent of the nature of the electrode used. However, once thepolypyrrole had been deposited, for example onto gold, the subsequent oxidation process potentialoccurs at a slightly smaller value as compared to when deposition took place onto the glassy carbonelectrode, which suggests that different oligomeric pyrrole species Pyn, are undergoing oxidation,implying a strong dependence on the substrate nature. The potentiostatic transients studied for bothsubstrates revealed that polypyrrole formation kinetics is also dependent on the said electrodenature, to the extent that under potentiostatic conditions, the formation kinetics was appreciably slowerin gold as compared to that observed in glassy carbon. It was shown that polypyrrole electrodepositionon gold electrode follows, for the lowest applied potential considered, an oxidation, precipitation andgrowth mechanisms that could also explain the experimental current transients recorded forpolypyrrole formation on glassy carbon electrode.
展开▼
