A.S. Adekunle, O.A. Arotiba, B.O. Agboola, N.W. Maxakato, B.B. Mamba, E.E. Ebenso
North-West University, ZA
voltammetry, impedance studies, phenols, carbon nanotubes, Prussian blue films
Phenols and the chlorinated and alkylated derivatives are classified as priority pollutants due to the health risk associated with their toxicity. Due to their constant presence in industrial waste and consequently their carcinogenic risk for humans, methods for the detection of phenol and chlorophenols and quantification are important. Electrochemical method is the most efficient since it takes a shorter time with no chemical derivatization and gives very reproducible results compare with common methods of analysis. Recently the oxidation of phenols and chlorophenols on modified electrodes with different kinds of catalysts have been reported and it is usually associated with adsorbed oxidation intermediates which poison the surface due to polymer formation during the oxidation process. Our motivation for this work is to develop and investigate the resistance of platinum electrode modified with multi-walled carbon nanotubes/Prussian blue nanocomposite (Pt-MWCNT-SO3--PB) towards electrode poisoning by polyphenols intermediates during phenol and its derivatives oxidation. The modified electrodes were characterized using microscopic, spectroscopic and electrochemical impedance spectroscopy (EIS) techniques. Pt-MWCNT-SO3--PB electrode gave the highest electro-oxidation current compared to the other electrodes studied. The oxidation of the phenol compounds was not completely diffusion controlled, and the electrode was characterized by some level of adsorption.