Resumo

GUAUS, E.  e  TORRENT-BURGUES, J.. Electrochemical Response of a Vitreous Carbon Electrode Modified by a Thiomacrocyclic Compound Film. Port. Electrochim. Acta [online]. 2007, vol.25, n.1, pp.139-152. ISSN 0872-1904.

A Langmuir-Schaefer (LS) film of a thiomacrocyclic (ThM) compound was deposited on the surface of a glassy carbon electrode (GCE) rod, from a subphase containing Cu(II) ions. The voltammetric response of this modified GCE when the ThM was bonded to Cu^2+, showed that the LS film moved the oxidation peaks of copper to more positive values. On the other hand, a LS film of the ThM compound was deposited on the surface of a GCE rod from a subphase of pure water. When the voltammetric response of the GCE-ThM electrode was studied in a Cu²⁺-SO₄^2- solution, it was found that the modified electrode increases its sensitivity respect to Cu²⁺ at low bulk Cu²⁺ concentrations in solution, and a surface-complexation reaction is proposed to explain the effect of the LS film on the GCE surface.

Palavras-chave : modified electrodes; Langmuir-Schaefer films; cyclic voltammetry; surface-complexation reaction.

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