Emulsion template synthesis of all conducting polymer aerogels with superb adsorption capacity and enhanced electrochemical capacitance

Abstract

4-(2,3-Dihydrothieno[3,4-b][1,4]dioxin-2-yl)-methoxybutane-1-sulfonate (EDOT-S) as a reactive surfactant was used to disperse 3,4-ethylenedioxythiophene (EDOT) to make a PEDOT-S/PEDOT hydrogel by emulsion polymerization. The corresponding all conducting polymer aerogels have been obtained by supercritical drying or freeze drying of the as-synthesized PEDOT-S/PEDOT hydrogels. The stability of the EDOT-S stabilized EDOT emulsion has been investigated by zeta potential and size tests. The mechanical property and gelation mechanism of the resulting PEDOT-S/PEDOT hydrogels have been studied by rheological experiments, X-ray powder diffraction and X-ray photoelectron spectroscopy. The molecular structure of the resulting PEDOT-S/PEDOT aerogels has been revealed by infra-red and Raman spectroscopy, and the porous attribute of the as-synthesized PEDOT-S/PEDOT aerogels has been investigated by scanning electron microscopy, transmission electron microscopy and nitrogen sorption tests. It has been found that molar ratios of EDOT-S to EDOT have played a significant role in determining the stability of the resulting emulsion, the mechanical properties of the resulting hydrogel, and the porous properties of the resulting aerogels. The electrical, electrochemical and adsorption properties have also been disclosed in this manuscript. The results show that the as-prepared all conducting polymer aerogels have high conductivity with the level of 10¹ S m⁻¹, enhanced electrochemical capacitance with good rate capability and excellent cycling stability, and superb adsorption capacity to dyestuff and heavy metals ions.