Electrochemical preparation of poly(vinylferrocenium)perchlorate-polyaniline composite-modified platinium electrode in methylene chloride

Abstract

A new surface based on poly(vinylferrocenium)perchlorate-polyaniline (PVF+ClO4–-PANI) composite-modified platinum electrode was prepared electrochemically to combine the electrocatalytic properties of an intrinsically conducting polymer and a redox polymer. The composite film was synthesized as a bilayer from individual polymerization solutions. Furthermore, PVF+ClO4– and PANI polymers were simultaneously deposited as a mixture from a methylene chloride solution containing PVF polymer and aniline monomer on Pt electrode. When PVF+ClO4– and PANI were codeposited by cycling the potential between 0.20 and 1.80 V vs Ag|AgCl, these polymers were encapsulated within each other. The encapsulation of PVF+ClO4– inside the growing PANI polymer provided the retainment of PVF+ClO4– on the electrode surface even if it was in dedoped form (PVF). This composite film was characterized by cyclic voltammetry, FTIR, SEM and conductivity measurements. The response of the composite film to catechol and hydroquinone was investigated by chronocoulometry in aqueous medium. It was found that the increase in charge consumption for catechol and hydroquinone was observed up to 7.5 and 5.0 times, respectively, when compared to that of PANI film. This might be due to the presence of PVF+ClO4– in the composite film, which played an important role in accelerating the electron transfer.