Studies On Modified Electrodes Of Planar Binuclear Cobalt Phthalocyanine And Its Doped With Polyaniline Film

The synthesis and electrochemical properties of a planar binuclear cobalt phthalocyanine(bi-CoPc) modified electrode were studied in this paper. Also, after incorporation of bi-CoPcinto polyaniline (PAn), we investigated the effect of the ethanol concentration on propertiesof bi-CoPc-PAn modified electrodes. In the first part of this work, we studied the electrochemical behavior of bi-CoPcadsorbed on glassy carbon (GC) electrodes. The electrochemical growth using cyclicvoltammetry (CV) was carried out. In the second, the effect of the concentration of ethanolwas investigated by CV, UV-vis spectroscopy, FTIR spectroscopy, scanning electronmicroscope (SEM). The following results have been found: (1) The chemically modified electrode shows strong electrocatalytic activity for oxygendissolved in solution and four-electron of two steps reduction of O2 to H2O when pH valuesare greater than 3 seems to be the mechanism. Two peak potentials corresponding toreduction of O2 to H2O2 and H2O2 to H2O are -155 mV and -467 mV respectively in B-Rbuffer solution with pH 4.1. The planar binuclear cobalt phthalocyanine adsorbed on glassy carbon electrode exhibitssubstantial electrocatalytic activity for the oxidation of 2-mercaptoethanol (2-ME). The peakpotential for oxidation of 2-mercaptoethanol was –200mV at pH 12. (2) The concentration of ethanol affects the electropolymerization rate, surfacemorphology and electrocatalytic activities of PAn films grown in the presence of bi-CoPc.The ethanol additions enhance the electropolymerization rate and lead to the net-chainstructure of PAn film. It is found that the electrocatalytic activity of bi-CoPc-PAn modifiedelectrodes towards oxygen reduction is higher in presence of ethanol than that of its absence.