title: Reduction of hexavalent chromium at solid electrodes in acidic media: reaction mechanism and analytical applications.
abstract: The electrochemical detection of hexavalent chromium species was investigated. It was found that Cr(VI) can undergo chemically irreversible reduction in acidic solutions at gold, glassy carbon and boron-doped diamond electrodes. The process was found to be diffusionally controlled at all three electrodes studied. The response obtained at a gold electrode towards the reduction of chromium(VI) produced an electrochemically reversible wave in contrast to those recorded at glassy carbon and boron-doped diamond electrodes. The analytical response of the hexavalent species was studied at gold electrodes in the presence of common environmental interferences: Ni(2+), Cu(2+), Fe(3+), Cr(3+) and Triton X-100 (surfactant), with an LoD of 4.3muM obtained in the presence of 5mM Cr(III).
authors.affiliation: Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, UK.
authors.forename: Christine M
authors.initials: CM
authors.lastname: Welch
authors.forename: Olga
authors.initials: O
authors.lastname: Nekrassova
authors.forename: Richard G
authors.initials: RG
authors.lastname: Compton