One-step synthesis of biomass derived O, N-codoped hierarchical porous carbon with high surface area for supercapacitors

We report a convenient method to synthesize O, N-codoped hierarchical porous carbon by one-step carbonization of the mixture of KHCO3, urea and alginic acid. Benefiting from KHCO3 and urea synergistic effect, the obtained O, N-codoped hierarchical porous carbon (NPC-700) material has a well-developed interconnected porous framework with ultrahigh specific surface area (2846 m(2)/g) and massive heteroatoms functional groups. Consequence, such porous carbon displays high specific capacitance (324 F/g at 1 A/g), excellent rate performance (212 F/g at 30 A/g) and good electrochemical stabilization in 6 mol/L KOH solution. More importantly, the assembled NPC-700//NPC-700 symmetrical supercapacitor can achieve a high energy density of 18.8 Wh/kg and good electrochemical stabilization in 1 mol/L Na2SO4 solution. This process opens up a new way to design heteroatoms-doped hierarchical porous carbon derived from biomass materials for supercapacitors. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.