UV/ozone pretreatment of glassy carbon electrodes

A commercial UV/ozone cleaning device is investigated for use in pretreatin g glassy-carbon (GC) electrodes. In combination with alumina polishing, UV/ ozone pretreatment produces electrodes with high activity for oxidation of catecholamines and ascorbic acid. UV/ozone treatment also reverses the pass ivating effect of sonicating GC electrodes in protic solvents and minimizes adsorption of dopamine and 4-methyl catechol. UV/ozone treatment also clea ns electrodes fouled by electrolysis by-products. Fifteen minutes of UV/ozo ne treatment produced near complete restoration of activity at a GC electro de passivated by a phenolic polymer film. UV/ozone treatment increases acti vity by oxidative removal of organic adsorbates and a polishing-produced ca rbon-powder overlayer. In addition, XPS and cyclic voltammetry indicate tha t carbon-oxide concentration increases on the surface of the UV/ozone treat ed carbon electrode as compared to an alumina-polished electrode. (C) 2001 Elsevier Science B.V. All rights reserved.