SPECTROELECTROCHEMISTRY OF POLYANILINE AT LOW CONCENTRATIONS OF DOPING ANIONS

Spectroelectrochemical techniques combined with cyclic voltammetry wer e applied to the investigations of polyaniline synthesized electrochem ically in acid solutions. Voltammetric current response of the polymer films was measured in solutions containing tungstosilicic acid (i.e. supporting electrolyte with anions too large to dope the polymer) and various amounts of HClO4. Simultaneously UV-VIS spectra were recorded. The concentration of small anions capable of doping the polymer was g radually increased. The nature of ionic species and their concentratio n significantly affect electrochemical and spectroelectrochemical prop erties of polyaniline.