Proton Exchange during the Redox Switching of Polyaniline Film Electrodes

摘要

Proton ejection/injection during the redox switching of polyaniline (PANI) have been qualitatively measured employing the rotating ring-disk electrode in the amperometric mode at the ring. The ring response shows that there is proton ejection during the oxidation of a fully relaxed polymer both from the leucoemeraldine to emeraldine forms and from it to the fully oxidized form. During the reduction of the polymer there is proton injection. However, this process is incomplete for the emeraldine/leucoemeraldine transition, indicating proton equilibration is a slow process. The ring response during the second positive half-potential sweep (nonrelaxed polymer) shows that the ring current is much smaller, indicating the polymer is not in protonic equilibrium with the external electrolytic phase.