Electrooxidation of phenol in alcohols and establishment of the permeability of the electrodeposited films

In this work, electrooxidation of phenol was studied in different alcohols (methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol, 2-methyl-1-propanol and benzyl alcohol) at platinum electrode. The electrode fouled in all alcohols during the subsequent cyclic voltammetric scans and poly(phenylene oxide) formed on the electrode surface which was then characterized by Raman spectroscopic studies. The spectra of films deposited from the different alcohols were very similar indicating the uniform composition of the electrodeposited polymer films. Electrolysis of alcoholic phenol solutions at the corresponding constant potential and the subsequent fluorescence studies showed that no soluble polymer formed during the anodic oxidation and each polymer adsorbed on the electrode surface. Permeability studies of the electrodeposited polyphenols using 1,4-dihydroxybenzene as a redox probe showed high diffusion hindrance in case of all alcohols except for benzyl alcohol where phenol electrodeposited mainly in separated islands. Heat treatment at 150 °C enhanced the decrease in permeability.