The electrochemical oxidation of hydroquinone and catechol through polyaniline and poly(aspartic acid) thin films: A comparative study

Abstract

Lately, polymers as electrochemical catalysts have attracted intense interest. As two promising candidates, herein, electrochemically deposited polyaniline and poly(aspartic acid) thin film materials have been fabricated on glassy carbon electrodes. Through multiple characterizations, including attenuated total reflection Fourier transform infrared spectrophotometry, cyclic voltammetry, electrochemical impedance spectroscopy, and proton nuclear magnetic resonance, essential properties of these two electro-synthesized polymers, especially the capacity in electrochemically catalyzing the oxidation of electro-active isomers of hydroquinone and catechol, have been investigated. The polymer-modified electrodes present improved conductivity, and diffusion-dominated redox behaviors of hydroquinone and catechol at both modified glassy carbon electrodes are observed. In addition, quantitative proton nuclear magnetic resonance spectra provide the evident information on the electrochemically induced molecular transformation, which confirms the better electrochemical activity of poly(aspartic acid).