110 Triarylamine-Based Conducting Polymer Electrodes for Supercapacitors

Wednesday, November 4, 2009: 3:10 PM
Charolais (Camino Real Hotel)
Mark E. Roberts , Sandia National Laboratories, Albuquerque, NM
David R. Wheeler , Sandia National Laboratories, Albuquerque, NM
Bonnie B. McKenzie , Sandia National Laboratories, Albuquerque, NM
Bruce C. Bunker , Sandia National Laboratories, Albuquerque, NM
Supercapacitors are electrical energy storage devices combining the high power, rapid switching, and exceptional cycle life of a capacitor with the high-energy density of a battery. Power sources based on supercapacitors are emerging as a viable option for applications requiring short power pulses, particularly when combined with conventional batteries. In order to maximize capacitance, switching speed, and power, materials for supercapacitors must incorporate conductive and redox-active materials into high surface area structures engineered to provide intimate contact between the redox sites and the electrolyte. Conducting polymer are well-suited to address these challenges owing to the myriad of synthetic and processing methods which result a in a variety of nanostructures and electrical behaviors.

In this presentation, we will present novel conducting polymers for the electrode material of electrical energy storage devices, specifically, polymers consisting of triphenylamine centers with various thiophene moiety side-groups. The monomers were synthesized using Stille coupling chemistry and used to fabricate porous electrode structures via electrochemical polymerization on conducting substrates. The electrodes were characterized structurally with scanning electron microscopy and electrochemically with cyclic voltammetry, charge-discharge and electrical impedance spectroscopy. Electrodes structures fabricated with these polymers exhibited a remarkably high specific capacitance of up to 950 F/g in 100 mM tetrabutylammonium tetrafluoroborate in acetonitrile with power and energy densities greater than 6 kW/kg and 25 W-hr/kg, respectively. The electrical performance of the electrodes in electrochemical half-cells, reported for highly porous and nanotube electrodes, is used to provide insight into the electrochemical storage mechanism of polymer-based systems.

*Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.