The problem of the low-frequency dispersion in the case of polymer film electrodes - an experimental impedance study on Au/poly (o-phenylenediamine) electrodes

Electrochemical impedance spectra are presented for Au\poly( o-phenylenedia mine) electrodes in contact with 1 mol dm(-3) perchloric acid solution. The roughness of the gold substrate and the film thickness, respectively, were systematically varied. The results obtained affirm that the dispersion of the low-frequency capacitance is connected with the inhomogeneity of the su rface film, and the role of the surface roughness of the gold substrate is minor, if any, in the development of the CPE behaviour, which is in contras t to some hypotheses presented recently. (C) 2000 Elsevier Science S.A. All rights reserved.