Impedance spectroscopy study of conducting polymer blends of PEDOT:PSS and PVA

Blends of the conducting polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) with polyvinyl alcohol (PVA) have many potential applications including microelectromechanical systems (MEMS) and other electronic devices. Specifically, PEDOT:PSS acts as the electrical conductor, while the PVA provides ductility and other mechanical enhancements. Concentrations of PEDOT:PSS at 20, 30 and 40 weight percentage (wt%) in PEDOT:PSS/PVA mixtures have been found to provide optimal mechanical and electrical properties. PEDOT:PSS/PVA films are prepared using a casting method and electrochemical impedance spectroscopy is used to investigate the electrical properties. The extrapolated DC conductivities are obtained in a dry nitrogen environment at room temperature and determined to be 3.917×10−8, 2.383×10−7 and 8.369×10−6S/cm, respectively, for 20, 30 and 40wt%. In addition, as a means to better explore the conduction as a function of temperature, impedance spectroscopy measurements for the 30wt% PEDOT:PSS are determined over a range of temperatures from 24.5°C to 79.5°C. The corresponding extrapolated DC conductivities are found to increase by a factor of about four with increase in temperature from 4.617×10−8S/cm at 24.5°C to 2.083×10−7S/cm at 79.5°C.