Active Carbon-Based Electrode Materials from Petroleum Waste for Supercapacitors

A supercapacitor is an energy-storage device able to store and release energy at fast rates with an extended cycle life; thus, it is used in various electrical appliances. Carbon materials prepared above 800 degrees C of activation temperatures are generally employed as an electrode material for supercapacitors. Herein, we report carbon materials prepared from a low-cost petroleum waste carbon precursor that was activated using KOH, MgO, and Ca(OH)(2) only at 400 degrees C. Electrode materials using low-temperature activated carbons were prepared with commercial ink as a binder. The cyclic voltammetry and galvanostatic charge-discharge were employed for the electrochemical performance of the electrodes, and studied in a 3-electrode system in 1 M solutions of potassium nitrate (KNO3) as electrolyte; in addition, the supercapacitive performance was identified in a potential window range of 0.0-1.0 V. The best-performance activated carbon derived from vacuum residue with a specific surface area of 1250.6 m(2)/g exhibited a specific capacitance of 91.91 F/g.