High Energy Density Supercapacitor Based on a Hybrid Carbon Nanotube - Reduced Graphite Oxide Architecture

E. Bekyarova, P. Ramesh, N. Jha, M.E. Itkis, R.C. Haddon
Carbon Solutions Inc, US

Keywords: single wall carbon nanotubes, reduced graphite oxide, supercapacitor, synergistic effect energy density

Summary:

We report a high energy supercapacitor device that utilizes hybrid carbon electrodes and the ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF¬4) as an electrolyte. The hybrid electrodes were prepared from reduced graphite oxide (rGO) and purified single walled carbon nanotubes (SWNTs). A simple casting technique gives a hybrid structure with optimum porosity and functionality that provides high energy and power density. The combination of SWNT and rGO in a weight ratio of 1:1 was found to afford specific capacitance of 222 F/g and energy density of 94 Wh/kg at room temperature.