The mediatory activity of meso-tetraphenylporphyrin iron(III) compleximmobilized in Na on lm on a Pt electrode in the oxidation of 1,2- and1,4-hydroquinones

Abstract

This paper presents the results of an investigation of the properties of a modi ed platinum electrode withmeso-tetraphenylporphyrin iron(III) complex immobilized in Na on lm and its catalytic activity in the electrochemicaloxidation of selected hydroquinone and catechol derivatives.The redox activity of iron complexes of porphyrins wascharacterized in aqueous solutions of perchloric acid by means of cyclic voltammetry and differential pulse voltammetry.Both the increase in the anodic peak currents of the investigated compounds during oxidation on the platinum electrodemodi ed withmeso-tetraphenylporphyrin iron(III) complex immobilized in Na on lm (FeTPhP/Na on/Pt) and theconsiderable decrease in the cathodic peak currents related to the porphyrine complexes reduction point to mediatoryactivity. The increase in the oxidation currents observed during the preparative electrolyses indicates that the modi edplatinum electrode, FeTPhP/Na on/Pt, exhibits catalytic properties. The preparative electrooxidation of the investi-gated 1,2- and 1,4-hydroquinone derivatives showed that over 90% conversion of the substrate occurs in the shortest timeon platinum modi ed with iron complex of porphyrin immobilized in Na on film.