Biomass-derived porous carbon electrodes for high-performance supercapacitors

Biomass-derived porous carbon materials have been receiving considerable attention in energy-storage devices by virtue of the abundant and renewable sources. In this work, we developed a facile, yet scalable fabrication of nitrogen doping porous carbon (QPC-3) with high specific surface area (SSA) of 2597 m2 g−1 derived from quinoa. The QPC-3 electrode exhibits a special capacitance of 330 F g−1 in 6 M KOH at a density of 1 A g−1 and a good rate capability. Additionally, symmetrical supercapacitors assembled by QPC-3 can deliver capacitances of 254 F g−1 and 99.2 F g−1 at 0.5 A g−1, and the energy densities approach 9.5 Wh kg−1 and 22 Wh kg−1 in aqueous and organic electrolyte, respectively. The results suggest that this quinoa-derived porous carbon could be a promising biomass-derived electrode material applied in high-capacitance supercapacitors.