Electrochemical polymerization of thiophene under ultrasonic field

Abstract

Films of polythiophene were prepared by electrochemical oxidation under ultrasonic field. The ultrasonic irradiation had an influence on the conditions and the properties of the as-polymerized films. In the absence of ultrasonic irradiation, the as-polymerized films became brittle gradually when the electrolytic current density exceeded the value of 5 mA/cm 2. Whereas flexible and tough films with the tensile modulus of 3.2 GPa and strength of 90 MPa were obtained even at a high current density of 10 mA/cm 2 with ultrasonic irradiation. The doping level increased with increasing electrolytic current density, further, at a given current density, the levels for the irradiated series were higher than those for unirradiated series, which lead to a high electrical conductivity (130–150 S/cm) for the irradiated series. Cyclic voltammetry implied a higher diffusion rate for the films prepared under ultrasonic field compared with that for prepared without irradiation.