Physical, electrochemical and supercapacitive properties of activated carbon pellets from pre-carbonized rubber wood sawdust by CO2 activation

The physical and electrochemical properties of the activated carbon pellet electrodes have been investigated. Activated carbon pellets were prepared from single step carbonization process of pre-carbonized rubber wood sawdust at a temperature of 800 degrees C that followed with a CO2 activation process at temperature in the range of 700-1000 degrees C. The BET characterization on the sample found that the surface area of the carbon pellet increased with the increasing of the activation temperature. The optimum value was as high as 683.63 m(2) g(-1). The electrical conductivity was also found to increase linearly with the increasing of the activation temperature, namely from 0.0075 S cm(-1) to 0.0687 S cm(-1) for the activation temperature in the range of 700-1000 degrees C. The cyclic voltammetry characterization of the samples in aqueous solution of 1 M H2SO4 also found that the specific capacitance increased with the increasing of the activation temperature. Typical optimum value was shown by the sample activated at 900 degrees C with the specific capacitance was as high as 33.74 F g(-1) (scan rate 1 mV s(-1)). The retained ratio was as high as 32.72%. The activated carbon pellet prepared from the rubber wood sawdust may found used in supercapacitor applications. (C) 2010 Elsevier B.V. All rights reserved.