Chitosan gel synthesis nitrogen-doped porous carbon as electrode materials for supercapacitors

Abstract

Herein, chemical activation of chitosan gel by KNO3 to prepare nitrogen-doped carbon. The sol-gel method enabled the activation agent KNO3 to be evenly dispersed in the carbon precursor, thereby getting a better activation effect, while the carbonized gel could produce more pores, resulting in a larger specific surface area of the material. Meanwhile, biomass chitosan was cheap and comes from a wide range of sources. The synthesized nitrogen-doped carbon (CUFK) material showed a unique graded pore structure, large specific surface area (678.8 m2 g−1) and N, O content (8.6%, 13.5%). Applied in the field of supercapacitors, it exhibited good capacitive performance (329.2 F g−1 in 6 M KOH electrolyte at 0.5 A g−1) and good cycle performance (only loss of 8.4% for 10000 cycles). These results show that the prepared nitrogen-doped porous carbon materials have good capacitive capacity, which provides a strategy for green production of carbon materials.