The Electrochemical Behaviour of PEDOT Film Electrosynthesized in Presence of Some Dopants

Electropolymerization and characterization of poly(3,4-ethylene dioxythiophene) (PEDOT) doped with functionalized single-walled carbon nanotubes (SWANTs) polyaminobenzene sulfonic acid (PABS) and different dopants were studied. It was fabricated by a simple oxidative electropolymerization method. The nanocomposite coatings have been prepared by using electrochemical methods from aqueous solutions, such that the components were deposited onto platinum electrode substrate. The morphology of composite films was analyzed by scanning electron microscopy (SEM). The electrochemical and physical properties of the resulting composites were evaluated by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and Fourier transform infrared spectroscopy (FT-IR) techniques in 0.1 M LiClO4 aqueous solutions. The value of specific electrochemical capacitance of the composite films is considerably higher than that of the pure polymers films. The improved properties of the electrodes were obtained by using these composite films. The dopant substances used were sodium dodecyl sulfate (SDS) and 1,2-Dihydroxy- benzene-3,5-disulfonic acid disodium salt hydrate (tiron).

Nanocomposites Based on Conducting Polymers and Functionalized Carbon Nanotubes with Different Dopants Obtained by Electropolymerization

Nanocomposite films based on poly (3,4-ethylenedioxy thiophene) (PEDOT), functionalized single-walled carbon nanotubes and different dopants were studied. It was fabricated by a simple oxidative electropolymerization method. The dopant substances used were SDS (Sodium dodecyl sulfate) and tiron (1,2-Dihydroxybenzene-3,5-disulfonic acid disodium salt hydrate). These nano-composite films were grown electrochemically from aqueous solutions such that constituents were deposited simultaneously onto substrate electrode. The synthetic, morphological and electrical properties of the nanocomposite films obtained were compared. Scanning electron microscopy (SEM) revealed that the composite films consisted of nanoporous networks of SWCNTS (single-walled carbon nanotubes) coated with polymeric film. Cyclic voltammetry (CV), electro-chemical impedance spectroscopy (EIS) and FT-IR spectroscopy demonstrated that these composite films had similar electrochemical response rates to pure polymeric films but a lower resistance and much improved mechanical integrity. The negatively charged functionalized carbon nano-tubes (CNTSF) served as anionic dopant during the electropolymerization to synthesize polymer/CNTSF composite films. The specific electrochemical capacitance of the composite films is a significantly higher value than that for pure polymer films prepared similarly. Using these composite films, the modified electrodes with improved properties were obtained. (In this paper, for simplicity, the SWANTs-COOH group will be noted CNTsF which means functionalized carbon nanotubes.)