Electrocapacitive properties of nitrogen-containing porous carbon derived from cellulose

A generalised approach to the preparation of nitrogen-containing porous carbon from cellulose for supercapacitor applications is demonstrated in this paper. A sample prepared at a carbonisation temperature of 600 degrees C with a specific surface area of 781 m(2) g(-1) and a pore volume of 0.68 cm(3) g(-1) displayed the best electrocapacitive performance. The well-developed porous structure coupled with the presence of nitrogen-containing functional groups along with nascent hydrogen enabled this sample to exhibit specific capacitances of 248 and 133 F g(-1) at current densities of 0.1 and 10 A g(-1), respectively, in a symmetric cell with 1 M aqueous H2SO4 solution as the electrolyte. With this electrode, about 89% of the initial capacitance is retained after 2000 cycles at a current density of 1 A g(-1). A symmetric super capacitor fabricated using this carbon in both electrodes exhibits an energy density of 14.6 Wh Kg(-1) at a power density of 63.5 W Kg(-1) and remains at 7.9 Wh Kg(-1) at a power density of 6500 W Kg(-1). (C) 2017 Elsevier B.V. All rights reserved.