Avoiding the use of corrosive activator to produce nitrogen-doped hierarchical porous carbon materials for high-performance supercapacitor electrode

Abstract The development of an effective route to high-performance nanoporous carbon electrode materials derived from cost-effective biomass is critical but remains a great challenging for supercapacitors. Nitrogen-doped hierarchical porous carbons (HPCs) were synthesized via two steps by using (CH 3 COOK) chemical activation method. To this end, beancurd was applied as the carbon source, and CH 3 COOK was used as the activator due to its non-toxic and mildness features, avoiding the use of corrosive activator (KOH, ZnCl 2 , etc.). The optimized carbon possesses a high BET specific surface area and nitrogen content are 1735 m 2  g −1 and 1.33 at.%, respectively. The electrochemical test was carried out in H 2 SO 4 and KOH aqueous electrolytes, the sample possesses ultrahigh specific capacitance of 315 and 245 F g −1 at 0.1 A g −1 , respectively. Furthermore, the hierarchical carbon-derived supercapacitor displayed excellent cycling stability at a current density of 1 A g −1 (about 93.5% retention after 10,000 cycles), compared favorably with the literature. This new strategy would open an exciting route to explore the micro- meso -macro hierarchical porous carbon, specially made from beancurd, as promising electrode material for electric double layer capacitors.