Activation of glassy carbon electrodes by photocatalytic pretreatment

Dumanli O., Onar A. N.

ELECTROCHIMICA ACTA, vol.54, no.26, pp.6438-6444, 2009 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 54 Issue: 26
  • Publication Date: 2009
  • Doi Number: 10.1016/j.electacta.2009.05.096
  • Journal Name: ELECTROCHIMICA ACTA
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.6438-6444
  • Keywords: Photocatalytic pretreatment, Glassy carbon, Electrode reactivity, Electrode cleaning, Electron transfer kinetics, HETEROGENEOUS PHOTOCATALYSIS, CYCLIC VOLTAMMETRY, TRANSFER KINETICS, LASER ACTIVATION
  • Ondokuz Mayıs University Affiliated: Yes

Abstract

This paper describes a simple and rapid photocatalytic pretreatment procedure that removes contaminants from glassy carbon (CC) surfaces. The effectiveness of TiO2 mediated photocatalytic pretreatment procedure was compared to commonly used alumina polishing procedure. Cyclic voltammetric and chronocoulometric measurements were carried out to assess the changes in electrode reactivity by using four redox systems. Electrochemical measurements obtained on photocatalytically treated GC electrodes showed a more active surface relative to polished CC. In cyclic voltammograms of epinephrine, Fe(CN)(6)(3-/4-) and ferrocene redox systems, higher oxidation and reduction currents were observed. The heterogeneous electron transfer rate constants (k(o)) were calculated for Fe(CN)(6)(3-/4-) and ferrocene which were greater for photocatailytic pretreatment. Chronocoulometry was performed in order to find the amount of adsorbed methylene blue onto the electrode and was calculated as 0.34 pmol cm(-2) for photocatalytically pretreated GC. The proposed photocatalytic GC electrode cleansing and activating pretreatment procedure was more effective than classical alumina polishing. Crown Copyright (c) 2009 Published by Elsevier Ltd. All rights reserved.