title: New aspects of the electroadsorption of ethyl xanthate on copper electrodes.
abstract: The interaction of the ethyl xanthate (EX) anion with a copper electrode in a borate buffer solution, pH 9.2, has been investigated by cyclic voltammetry (CV), electrochemical quartz crystal microbalance (EQCM), electrochemical impedance spectroscopy (EIS), and measurements of contact angle (CA) under controlled potential. The results obtained allow establishing that, in the potential range from -0.80 and -0.60 V, two parallel reactions were characterized. These reactions were the ethyl xanthate electroadsorption and the hydrogen evolution reaction (HER). This last reaction has not been described by previous authors. Besides, the EIS measurements show that the mechanism of the HER on copper electrodes is not affected by the presence of a ethyl xanthate species. The EQCM study shows that in the electrodesorption process the departure of each ethyl xanthate species from the copper electrode is accompanied with the simultaneous entry of four to five water molecules. This fact is in accordance with the number of copper atoms involved in the adsorption of one ethyl xanthate species.
authors.affiliation: Instituto de Química, Pontificia Universidad Católica de Valparaíso, Avda. Brasil 2950, Casilla 4059, Valparaíso, Chile.
authors.forename: Paula
authors.initials: P
authors.lastname: Grez
authors.forename: Carlos
authors.initials: C
authors.lastname: Celedón
authors.forename: Aurora
authors.initials: A
authors.lastname: Molinari
authors.forename: Alfonso
authors.initials: A
authors.lastname: Oliva
authors.forename: Marco
authors.initials: M
authors.lastname: Orellana
authors.forename: Ricardo
authors.initials: R
authors.lastname: Schrebler
authors.forename: Rodrigo
authors.initials: R
authors.lastname: del Río
authors.forename: Ricardo
authors.initials: R
authors.lastname: Córdova