UV/ozone pretreatment of glassy carbon electrodes

A commercial UV/ozone cleaning device is investigated for use in pretreating 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 passivating effect of sonicating GC electrodes in protic solvents and minimizes adsorption of dopamine and 4-methyl catechol. UV/ozone treatment also cleans electrodes fouled by electrolysis by-products. Fifteen minutes of UV/ozone treatment produced near complete restoration of activity at a GC electrode passivated by a phenolic polymer film. UV/ozone treatment increases activity by oxidative removal of organic adsorbates and a polishing-produced carbon-powder overlayer. In addition, XPS and cyclic voltammetry indicate that carbon-oxide concentration increases on the surface of the UV/ozone treated carbon electrode as compared to an alumina-polished electrode.