A study of the fractal dimensions of the electrodeposited poly-ortho-aminophenol films in presence of different anions

Fractal dimensions of the electrodeposited poly-ortho-aminophenol (POAP) fi lms formed in the presence of Cl-, SO42-, NO3- and ClO4- anions are investi gated by the methods of electrochemical impedance spectroscopy and cyclic v oltammetry. In the former, the extent of the "squashedness" of the semi-cir cle in the Nyquist plods and in the latter the slope of maxima of the diffu sion current vs. the potential sweep rates in the logarithmic scale are use d. The fractal dimensions in the 2.33-2.46 range are obtained and good agre ement exists between the findings of the two methods. The length scale, the distances between two nearest points that the anions somehow sense (by a y ardstick of the size of their jump-lengths), were also derived and were fou nd to be in the 1.4-11.7 Angstrom range. (C) 2000 Elsevier Science S.A. All rights reserved.