Competitive doping in heterocyclic conducting polymers

✍ Scribed by D. J. Walton; S. Ryley; I. V. F. Viney; E. Taylor

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 350 KB
• Volume: 6
• Category: Article
• ISSN: 1616-301X
• DOI: 10.1002/(sici)1099-0712(199609)6:5/6<395::aid-amo291>3.0.co;2-o

✦ Synopsis

The preferential incorporation of perchlorate into the polymer, from electrolyte solutions also containing hexafluorphosphate, a phenomenon previously observed during the preparation of polypyrrole, has now been shown to take place in substituted derivatives of polypyrrole, polythiophene and also in polyazulene. In these ring systems the presence of electrondonating side groups enhances the effect. Preferment of perchlorate to various degrees is seen in all systems so far studied, including a number of different solvents, and is strongest in solvents of low nucleophilicity, such as nitromethane. Polypyrrole and polythiophene from acetonitrile solutions that contain only the respective anions show a higher dopant ratio in perchlorate-containing films compared with hexafluorophosphate films, suggesting that the competitive doping effect between these anions results from preferential perchlorate compensation of cationic species produced during the polymerisation.