RT Journal Article
T1 A Contribution on the Elucidation of the Electrooxidation Mechanism of Gentisaldehyde on a Glassy Carbon Electrode
A1 Estévez Brito, Rafael
A1 Rodríguez Mellado, José Miguel
A1 Palma López, Alberto
A1 Ruiz Montoya, Mercedes
A1 Rodríguez Amaro, Rafael
A1 Mayén, Manuel
AB The electrochemical behavior of gentisaldehyde (2,5-dihydroxibenzaldehyde) on a glassy carbon electrode is studied by linear-sweep cyclic voltammetry finding one to three oxidation peaks, depending on both the number of cycles recorded and the pH, and one reduction peak. The oxidation product was the formyl-p-benzoquinone, generated by the oxidation of the biphenolic ring, and not the 2,5-dihydroxybenzoic acid (gentisic acid) that could be formed by oxidation of the aldehyde group. The mechanism proposed at pH < pK1 (8.42) from the analysis of cyclic and convoluted voltammograms involves the loss of an H+ ion from one hydroxyl group, a first quasi-reversible electron transfer to give a radical, and the release of a proton in a third step (the r.d.s.) followed by the second electron transfer to give the product. At pK1 < pH < pK2, the electroactive species is the anion that losses an ion H+ to give the dianion, the process being of the CEE type (chemical-electrochemical-electrochemical steps). At pH > pK2 (10.93) the process becomes of the EE type (electrochemical-electrochemical steps), no H+ ions being involved. Radicals species found justify the antioxidant capacity of gentisaldehyde.
PB The Electrochemical Society
SN 0013-4651
SN 1945-7111 (electrónico)
YR 2016
FD 2016-10-28
LK https://hdl.handle.net/10272/23351
UL https://hdl.handle.net/10272/23351
LA eng
NO Brito, R. E., Mellado, J. M. R., Palma, A., Montoya, M. R., Rodríguez-Amaro, R., & Mayén, M. (2016). A Contribution on the Elucidation of the Electrooxidation Mechanism of Gentisaldehyde on a Glassy Carbon Electrode. In Journal of The Electrochemical Society (Vol. 163, Issue 14, pp. H1127–H1131). The Electrochemical Society. https://doi.org/10.1149/2.0491614jes
NO Funding from Córdoba University through “Ayudas puente para el desarrollo de proyectos de I+D precompetitivos XX Programa Propio 2016” is gratefully acknowledged.
DS Repositorio Institucional de la Universidad de Huelva
RD 1 jun 2026