PROPERTIES OF POLY(O-PHENYLENEDIAMINE)-FI LM COATED ELECTRODE AND ITSEFFECT ON KINETICS OF BENZOQUINONE REDUCTION

The electrochemical behaviour of poly-o-phenylenediamine (PPD) film co ated electrode in pH 7.0 phosphate buffer solution was studied by volt ammetry and in-situ IR reflectance spectroscopy, The results showed th at PPD exhibits redox activity at the potentials more negative than 0. 0 V(SCE), and the redox process is accompanied by doping and undoping of H2PO4- ions, showing that the polymer is positively charged, The re duction of benzoquinone at the PPD electrode occurs in the electroacti ve potential range of PPD, RDE experiments indicated that benzoquinone is able to penetrate into the polymer matrix and exchange electron wi th the polymer, According to the model of PPD as a conducting polymer, the kinetics of benzoquinone reduction was analyzed and the influenci ng factors were discussed.