Electrical property and stability of electrochemically synthesized polypyrrole films

Polypyrrole (PPy) films doped with arylsulfonate dopants were prepared by electrochemical polymerization, to investigate the effects of various dopants on conductivities, thermal stabilities, and morphologies of PPy films. Also, HCl was added to those dopants as a cooperating dopant, to improve conductivity of PPy films. Conductivity of PPy film doped with the mixture of each dopant and HCl was improved. Temperature dependency on conductivity for PPy films doped with various dopants was investigated by heating them from 30 to 300degreesC. For the film doped with TSA, DBSA, and AQSA, conductivity increased up to 150degreesC and then rapidly decreased, whereas the conductivity of other films decreased after 200degreesC as temperature increased up to 300degreesC. Moreover, the film doped with small size dopant such as TSA and HCl/TSA had an interconnected porous fibrillar-like morphology. (C) 2004 Wiley Periodicals, Inc.