Anion and Solvent Exchange as a Function of the Redox States in Polyaniline Films

Polyaniline films are studied by using potentiodynamic experiments simultaneously with the electrochemical quartz crystal microbalance. The influence of the chemical nature of different anions on the electropolymerization of aniline is investigated. Also, the role of ionic transport during redox reactions is emphasized in order to obtain information about all chemical species involved in the process occurring in the conducting polymer film. The contribution of each species depends on the counterion used in the electropolymerization process. When the anion charge/size relationship decreases, the proton contribution to the electroneutralization process increases; there is also a diminution of solvent transport in the polymer/electrolyte interface.