The superior electrochemical performance of oxygen-rich activated carbons prepared from bituminous coal

Oxygen-rich activated carbons (OAC) were prepared from bituminous coal through a quick KOH activation. OAC exhibited a moderately large surface area of 1950 m(2)/g, a relative wide pore size distribution, good conductivity and very high oxygen content (up to 12 wt.%). Compared with high surface area activated carbons prepared by the conventional KOH activation, OAC have superior capacitive behavior, power output and high energy density in electrochemical double layer capacitors (EDLC). OAC presented a high specific capacitance of 370 F/g in 3 M KOH electrolyte at a low current density of 50 mA/g and still remained 270 F/g even at a high current density of 20 A/g. (c) 2008 Published by Elsevier B.V.