Abstract
Conducting polymers show great promise as supercapacitor materials due to their high theoretical specific capacitance, low cost, toughness, and flexibility. Poor ion mobility, however, can render active material more than a few tens of nanometers from the surface inaccessible for charge storage, limiting performance. Here, we use semi-interpenetrating networks (sIPNs) of a pseudocapacitive polymer in an ionically conductive polymer matrix to decrease ion diffusion length scales and make virtually all of the active material accessible for charge storage. Our freestanding poly(3,4-ethylenedioxythiophene)/poly(ethylene oxide) (PEDOT/PEO) sIPN films yield simultaneous improvements in three crucial elements of supercapacitor performance: specific capacitance (182 F/g, a 70% increase over that of neat PEDOT), cycling stability (97.5% capacitance retention after 3000 cycles), and flexibility (the electrodes bend to a <200 μm radius of curvature without breaking). Our simple and controllable sIPN fabrication process presents a framework to develop a range of polymer-based interpenetrated materials for high-performance energy storage technologies.
Highlights
Supercapacitors present a promising means to meet the demand for improved energy storage technologies, combining the high energy density of batteries and the high power density of conventional capacitors.[1]
Conducting polymers have emerged as competitive materials for this new class of supercapacitors based on their high energy and power densities, low cost, high conductivity, and robust mechanical properties such as flexibility and stretchability.[6,7]
Specific capacitance can be drastically improved by depositing thin layers of conducting polymer onto high surface area supports, such as metal oxide nanowire arrays[11,12] or carbon nanotube networks.[13−15] These structures allow for high mass loadings without burying much of the active material too far from the electrode−electrolyte interface to participate in charge storage reactions
Summary
Improve ion mobility by facilitating electrolyte infiltration into the electrode bulk.[16−18]. Our sIPN films (Figure 1b,c) are fabricated using a simple, two-step synthesis and demonstrate dramatically improved specific capacitance, cycling stability, and mechanical properties relative to electrodes made from conventional neat PEDOT. The ionically conductive PEO matrix acts as an ion reservoir surrounding the PEDOT, greatly reducing ion diffusion distances throughout the electrode relative to conventional structures This enables PEDOT even within the bulk of the electrodes to participate in charge storage, as demonstrated by the fact that the specific capacitance of our sIPNs remains relatively constant when increasing the film thickness from 50 to 130 μm (Figure S6).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
