Electrocataltyic oxidation of hydrazine at polymeric iron-tetraaminophthalocyanine modified electrodes

Electrocatalytic hydrazine oxidation was studied by using a glassy carbon e lectrode coated with monomeric and polymeric Fe-tetraaminophthalocyanine. T he polymeric complex-modified electrode is a better catalyst than the monom er-modified electrode. It presents higher activity at lower potentials and a very good reproducibility. A linear correlation between I,, and hydrazine concentration in a wide range, from 1 x 10(-6) to 1 x 10(-2) M at pH 13 fo r the polymer-modified electrode was obtained. The open circuit measurement s for the polymer-modified electrode in aqueous solution in both presence a nd absence of hydrazine show that an electronic transfer occurs without an applied potential, from the hydrazine to the Fe (II) metal center. The kine tic electro-oxidation parameters for the polymer-modified electrode were in vestigated and a probable mechanism operating at pH 13 is proposed. (C) 200 1 Elsevier Science B.V. All rights reserved.