THEORETICAL AND EXPERIMENTAL STUDIES OF CONDUCTING POLYMER POLYANILINE ELECTROLYTE INTERFACE BY IMPEDANCE SPECTROSCOPY

A fractal model is proposed to explain the origin of ''constant phase angle'' (CPA) elements often observed in interfacial impedance between blocking electrode and electrolyte. Universal relation between CPA ex ponent eta and surface fractal dimension D(s), eta = 3 - D(s), has bee n obtained. Based on our theoretical results, impedance spectroscopy c an be used as a new experimental approach for surface (interface) stud y, especially for conducting polymers. Some interesting information ab out structure and electrochemical polymerization process of polyanilin e have been obtained from impedance spectra of polyaniline / electroly te interface.