Abstract: A novel crystallite carbon (NCC)was prepared by KOH activation of carbonized petroleumcoke precursors. The porous structure, crystallite structure, and microstructure were characterized by N2 adsorption-desorption, X-ray diffraction (XRD), and high resolution transmission electron microscopy (HRTEM) measurements, respectively. The capacitive behavior of the NCC electrodes was also examined with 1 mol·L-1 tetraethylammonium tetrafluoroborate (Et4NBF4) solution in propylene carbonate (PC). It was found that the NCC was composed of much well-grown graphite-like crystallite with average interlayer spacing (d002) of 0.377 nm. The NCC had lower surface area (130.7 m2·g-1) and more distinct crystal character than activated carbon (AC). The energy storage for the NCC depended on the intercalation of electrolyte ions into graphite-like crystallite layers. The specific capacitance of the NCC was 110.6 F·g-1, showing specific energy of 27.5 Wh·kg-1, specific power of over 1.2 kW·kg-1 and excellent cycle stability. Therefore, the crystallite carbon is a promising candidate for novel electrode material.

Key words: Crystallite carbon, Graphite-like crystallite, Porous structure, Intercalation