High Power Density Supercapacitors Based on the Carbon Dioxide Activated D-Glucose Derived Carbon Electrodes and Acetonitrile Electrolyte

The electrochemical impedance spectroscopy, the cyclic voltammetry, and the constant power charge/dischaige methods have been applied to establish the electrochemical characteristics for the electrical double-layer capacitor consisting of the 1 M (C2H5)(3)CH3NBF4 electrolyte in acetonitrile. The microporous carbon electrodes prepared from D-(+)-glucose by the hydrothermal carbonization method and subsequent pyrolysis and carbon dioxide activation steps. The total Brunauer-Emmett-Teller specific surface area (S-BET <= 1539 m(2) g(-1)), micropore surface area (S-micro <= 1534 m(2) g(-1)), total pore volume (V-tot <= 0.694 cm(3) g(-1)) and the size distribution of the pores, obtained from the N-2 sorption data and using the non-local density functional theory, have been correlated with the electrochemical characteristics for electrical double-layer capacitors as the region of ideal polarizability (Delta E <= 3.0 V), characteristic time constant (0.34 s) and the high series capacitance (126 F g(-1)), dependent on the carbon activation conditions, have been calculated. (C) 2013 The Electrochemical Society. All rights reserved.