Multifunctional Electrodes Based on MWNTs Sheets and Yarns
J. Carretero-González, M.E. dela Cruz, S. Fang, J.P. Ferraris, R.H. Baughman
The University of Texas at Dallas, US
Keywords: MWCNT, supercapacitors, muscles, electrodes, polymer
Abstract:Solid-state fabricated carbon MWNTs sheets and yarns exhibit very high electrochemically accessible surface area, which combine with their high electronic conductivity and useful mechanical properties to make these materials attractive candidates for supercapacitor and artificial muscle applications. In this study we demonstrate the capacity of MWNT nanotube yarns and sheets to store and release energy. MWNT sheet electrodes were fabricated and assembled into solid-state devices, by employing a phosphoric acid/polyvinyl alcohol mixture as the polyelectrolyte. Using various device configurations, various sheet densities and polyelectrolyte/polymer/water concentration ratios were tested to determine the principal parameters affecting the formation of the electrochemical double-layer between the surface of the MWNTs and the polyelectrolyte. Electrode capacitances of between 50 and 150 F/g were obtained for these solid-state supercapacitors.