Preparation and Characterization of PEDOT/PSS Hybrid with Graphene Derivative Wrapped by Water-soluble Polymer

Post-Treatment of Tannic Acid for Thermally Stable PEDOT:PSS Film

As a poly (3,4-ethylenedioxythiophene) doped with poly (styrene sulfonate), PEDOT:PSS is well known for its conductive polymer in a field of organic electronics. PEDOT:PSS can be widely operated as electronics under low temperature conditions; however, the layer can be easily damaged by high temperature conditions, while in fabrication or in the operation of electronics. Therefore, enhancing the thermal stability of PEDOT:PSS can be a novel strategy for both fabrication and operating varieties. Herein, PEDOT:PSS is the surface-treated with tannic acid to increase the thermal stability. A large number of phenols in tannic acid not only provide UV absorption ability, but also thermal stability. Therefore, tannic-treated PEDOT:PSS film sustained 150 °C for 96 h because of its initial conductivity. Moreover, surface properties and its bonding nature was further examined to show that the tannic acid does not damage the electrical and film properties. The method can be widely used in the field of organic electronics, especially because of its high stability and the high performance of the devices.

Novel Approach to Introduce Alkyl Chains into PEDOT:PSS and Its Effect on the Performance as a Flexible Electrode

We here report a synthetic route to introduce alky chains into poly (3,4-ethylenedioxythiophene):poly (4-styrenesulfonate) (PEDOT:PSS) by the reaction with epoxyalkanes. The reaction was analyzed by FT-IR, TGA, and XPS studies, and the conductivities of derivatives were discussed as a function of the length of alkyl chains. PEDOT:PSS-C6, which is the product from a reaction with epoxyhexane, was well dispersed in methanol and transparent films from this dispersion were successfully prepared. PEDOT:PSS-C6 film showed an increase in hydrophobicity, resulting in enhanced water resistance compared to pristine PEDOT:PSS film, and a morphological study of the film exhibited clear phase separation similar to PEDOT:PSS doped by DMSO. We also observed an improvement in the conductivity and flexibility of PEDOT:PSS-C6 film compared to those of pristine PEDOT:PSS film. This study proposes a promising method to introduce alky chains into PEDOT:PSS and to develop a flexible electrode applicable to an environment where contact with water is unavoidable.