In situ SiO2 etching strategy to prepare rice husk-derived porous carbons for supercapacitor application

Abstract A simple, effective, and scalable mix and pyrolysis process was developed for preparing rice husk-derived porous carbon. The process involves only mixing and pyrolyzing of carbon–silica composites (product of pre-carbonized rice husk) and Polytetrafluoroethylene (PTFE) powders under inert atmosphere to form porous carbon materials without any SiO 2 residue. The fabrication process does not use any toxic or corrosive solution to etch the SiO 2 , which was more suitable for large scale production. The obtained porous carbon was endowed a desirable specific surface area (1550 m 2 /g) and porous structure with high mesoporosity of 52%. Electrochemical investigation measurements showed that the obtained porous carbon represents a good electrode candidate for supercapacitor, which displayed a high specific capacitance of 220 F/g at a current density of 0.5 A/g. In addition, the electrode displayed excellent cycling stability with a capacitance retention of about 98% over 10,000 cycles.