Doping properties of PEDOT films electrosynthesized under high frequency ultrasound irradiation

Abstract

The present study presents the use of high frequency ultrasound (500 kHz, 25 W) for 3,4-ethylenedioxythiophene (EDOT) electropolymerization in aqueous medium in order to investigate its effects on conducting polymer properties. It was shown that mass transfer increases under ultrasound irradiation which improved electropolymerization and the comparison with experiments carried out at the same mass transfer level (4.6 × 10(-5) ms(-1)) puts in evidence that stirring effect is not the only phenomenon induced by ultrasound during electrodeposition. PEDOT films elaborated under ultrasonication present increased doping levels revealed by X-ray Photoelectron Spectroscopy (XPS) analysis, especially in the case of thick films (measured by mechanical probe), thanks to better incorporation of counter ions within polymer matrix as another consequence of mass transport improvement under ultrasound and probably film heating by wave absorption for the highest thicknesses. A dilation of the film under sonication leading to an increase in film thickness was also highlighted. Finally, a refining of the surface structure was also observed via SEM imaging.

Electrochemical Systems for Renewable Energy Conversion from Salinity and Proton Gradients

“…PEDOT conductivity remains optimum due to continuous, uninterrupted π-conjugation. 75,76 3,4-Ethylenedioxythiophene (EDOT) is the monomer unit of PEDOT. EDOT polymerization is one of the most common methods to obtain PEDOT films.…”

“…Some aspects, like solvent, supporting electrolyte, electrode, polymerization potential, and applied electropolymerization method might have important effects on the film consisting of electropolymerized PEDOT; nevertheless, all these experimental conditions can be perfectly controlled. [75][76][77] PEDOT stands out among conducting polymers because it has high conductivity, approximately 500 S cm -1 ; it also presents good environmental stability, provides broad potential window, has a fast charge/ discharge process, and charge storage properties, which together increase the interest in supercapacitor materials. 78 During the charge/discharge process, the PEDOT charge compensation mechanism occurs predominantly with the help of anions (ClO 4 -, NO 3 -, SO 4 2-, and BF 4 -).…”

Morphological and adhesive properties of polypyrrole films synthesized by sonoelectrochemical technique

“…Moreover close to an interface, the collapse of cavitation bubbles becomes asymmetric and the generated micro-jets enhance mass transfer to the electrode surface, allowing its activation by impingement. The monomers are thus brought to the electrode interface more efficiently and a higher current density and better electropolymerization are obtained [65].…”

New Developments in Electrochemical Sensors Based on Poly(3,4-ethylenedioxythiophene)-Modified Electrodes

“…This new preparation procedure resulted in homogeneous size distribution within the range 5-17 nm. The use of ultrasounds in the electropolymerisation of conducting polymers on various substrates and the preparation of sonogel-based electrochemical sensors has been also reported [86][87][88][89][90][91][92]. Recently, a great deal of interest has been also devoted to the in situ preparation of Pt nanoparticles [93][94][95][96][97][98].…”