The influence of the monomer and the ionic liquid on the electrochemical preparation of polythiophene

Thiophene, bithiophene and terthiophene have been electropolymerised using ionic liquids as the growth medium and the supporting electrolyte. Both imidazolium and pyrrolidinium-based ionic liquids were used to assess the influence of the nature of the ionic liquid on the morphology and electrochemical activity of the conducting polymers. The pyrrolidinium-based ionic liquid produced slightly smoother films for all the thiophene species studied. A number of the polymers displayed multiple redox peaks, the possible origins of which are discussed. Both the ionic liquid and the choice of monomer had a significant influence on the polymer produced.