Electrochemistry of Ion-Selective Conducting Poly(3-methylthiophene): The Polymer, the Charge, and the Interface
By Ahmed, Galal
2003
Abstract
Conducting poly(3-methylthiophene) films were electrochemically deposited onto a platinum substrate. The resulting polymer film electrode was tested in different electrolytes and solvents using electrochemical impedance spectroscopy (EIS). The effect of exposure of the polymer film to iodine was also studied. From the impedance measurements, the values of parameters such as double layer capacitance, charge transfer resistance and diffusion coefficients were obtained. For the capacitance associated with the polymer, relatively large values have been found which vary as a function of the film potential and the electrolyte/solvent used. The capacitive component of the current was separated from the faradaic one during the charging/discharging process for films exposed to iodine. The results were used to interpret the selective nature of the polymer film towards ion recognition.