Abstract

Conducting polymer and self-assembled monolayer (SAM) of iron phthalocyanine complex are formed on glassy carbon electrode (GCE) and gold (Au) electrode, respectively. The polymer is formed via electropolymerization, while SAM is formed via self-assembly technique. Comparative studies of these techniques are carried out. Results of these studies show that the redox processes of the adsorbed species are closely related to those of the solution electrochemistry. Both ligand- and metal-based redox processes are observed on the MPc-polymer-modified surface, while only metal-based redox process is observed on the MPc-SAM-modified surface. Atomic force microscopic (AFM) images show differences in morphologies of the modified surfaces. Electrochemical impedance spectroscopic data suggest better electron transfer kinetics on the MPc-SAM-modified surface than that on the MPc-polymer-modified surface. The MPc-SAM-modified surface shows better electrocatalytic activity towards the oxidation of the herbicide, carbofuran, than the MPc-polymer-modified surface.