Varying carbon structures templated from KIT-6 for optimum electrochemical capacitance

Abstract

Bicontinuous ordered mesoporous carbons (OMCs), fabricated from a KIT-6 template using aluminosilicate as catalyst and furfuryl alcohol as carbon source, were successfully prepared and studied as electrodes in supercapacitors. Their structures were characterized by transmission electron microscopy (TEM), small-angle X-ray diffraction (SAXD) and N2 cryosorption methods. Using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), the capacitive performance of the OMCs was found to be strongly dependent on the mesostructure. Specific capacitance value greater than 130 F g-1 at 20 mV s-1 were obtained from an OMC that featured high surface area with the existence of additional large pores to enhance the specific capacitance at high discharge rate. For the OMC with the best performance, we found that a power density as high as 4.5 kW kg-1 at an energy density of 6.1 Wh kg-1 can be delivered when the discharge current density is 20 A g-1 and can also be continuously charged and discharged with little variation in capacitance after 2500 cycles. These results indicate that this OMC with optimized structure has potential to be used as a power component in electric vehicles. © 2010 Elsevier Ltd. All rights reserved.