Graphitized carbon from wastepaper as electrodes for high-performance electric double-layer capacitors

Graphitized carbon electrode material was prepared from wastepaper by graphitization in molten sodium metal. X-ray diffraction and Raman spectroscopy were used to investigate the structural change of resulted carbons, both of which well proved the formation of graphite structure. Graphitized carbons have surface area that is nearly 26 times larger than initial carbonized paper and exhibit better electrochemical performances. The electrochemical performances of graphitized carbons were investigated by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic charge–discharge methods. The cyclic voltammetry results show a maximum specific capacitance of 194 F g−1. Therefore, wastepaper can be a promising electrode material for high-performance electric double-layer capacitors (EDLCs).