Electroactive counter anions in conducting polypyrrole: hexacyanoferrate and heteropolytungstate ions

Conducting polypyrrole films containing hexacyanoferrate ions and heteropolytungstate ions were studied for their electrochemical properties. The polymers exhibited reversible redox properties to the anions in addition to those of the polypyrrole moiety. The heteropolytungstate ions were retained in the polymer matrix without being ion-exchanged after repeated potential cycles in aqueous or nonaqueous electrolyte solutions containing no heteropoly anions. The charge compensation is affected by the transport of cations.