A New Modified Electrode with a Copolymer of Aniline/Fe(III)-Tetrakis(Para-Aminophenyl)Porphyrin: Test of Its Electrocatalytic Activity Toward the Reduction of Molecular Oxygen and Oxidation of Ascorbic Acid and Sulfite Ion.

Abstract

The simultaneous electropolymerization of aniline and Fe-porphyrin in HCl by cycling the potential on glassy carbon (GC) and highly ordered pyrolytic graphite (HOPG) electrodes was studied by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and electrochemical techniques. A conducting copolymer thin film was produced, which was stable and contained a low quantity of porphyrin compared to aniline. Its electrocatalytic activity was tested for the reduction of molecular oxygen and also for the oxidation of ascorbic acid and sulfite anion. This activity was higher than that of the poly-porphyrin and the poly-aniline modified electrodes for these reactions. Here we describe in detail the electropolymerization process and the film morphology. The electrocatalytic behavior of the aniline and porphyrin homopolymers is compared to that of the aniline-porphyrin copolymer.