Electro-oxidation of phenol on polyethylenedioxythiophene conductive-polymer-deposited stainless steel substrate

Studies on the electrochemical oxidation of phenol are interesting because of the importance of removing phenol from contaminated water or industrial effluents. Deactivation of the anode due to the formation and adsorption of polyoxyphenylene on its surface is a common problem for a variety of electrode materials during phenol oxidation. Investigations on suitable anode materials, which can undergo no or moderate poisoning by polyoxyphenylene, are interesting. In this study, polyethylenedioxythiophene (PEDOT), which is coated on a stainless steel (SS) substrate, is investigated. The electro-oxidation rate of phenol is greater on the PEDOT/SS electrode than on Pt. Deactivation of the PEDOT/SS electrode is slower in relation to Pt. The oxidation of phenol on PEDOT/SS electrode occurs to form both polyoxyphenylene and benzoquinone in parallel. Cyclic voltammetry of phenol oxidation is studied by varying the concentration of phenol, sweep rate, and thickness of PEDOT. AC impedance studies indicate a gradual increase in polymer resistance due to adsorption of polyoxyphenylene during multisweep cyclic voltammetry. (C) 2008 The Electrochemical Society.