Resumo

PROENCA, L. et al. Electrochemical Oxidation of D-Sorbitol and D-Manitol on Platinum Monocrystalline Surfaces. Port. Electrochim. Acta [online]. 2003, vol.21, n.4, pp.327-343. ISSN 0872-1904.

The electrochemical oxidation of D-sorbitol and D-mannitol was studied on two sets of stepped platinum single-crystal surfaces vicinal to the basal plane (111), as well as on a set of surfaces with monoatomic steps vicinal to the surface Pt(100). The aim of this study, conducted by cyclic voltammetry, was to check the influence of the crystalline surface structure (regarding terrace and step orientations) on the electrochemical oxidation process of the two polyols in platinum. The electrochemical oxidation reactions of D-sorbitol and D-mannitol were shown to be markedly influenced by the symmetry of the bidimensional domains as well as by the distribution of the orientated defects (monoatomic steps) on the platinum surfaces. The introduction of orientated defects leads to a reduction on peak current densities along with an increase in activity at lower potentials. The terrace width is clearly decisive to the oxidation process on the set of surfaces belonging to the series Pt(S) [(n-1) (111) × (110)].

Palavras-chave : Electrochemical oxidation; D-sorbitol; D-manitol; platinum; single-crystal surfaces; monoatomic steps.

        · resumo em Português     · texto em Português     · Português ( pdf )