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 (CH3COOK) chemical activation method. To this end, beancurd was applied as the carbon source, and CH3COOK was used as the activator due to its non-toxic and mildness features, avoiding the use of corrosive activator (KOH, ZnCl2, etc.). The optimized carbon possesses a high BET specific surface area and nitrogen content are 1735m2g−1 and 1.33at.%, respectively. The electrochemical test was carried out in H2SO4 and KOH aqueous electrolytes, the sample possesses ultrahigh specific capacitance of 315 and 245Fg−1 at 0.1Ag−1, respectively. Furthermore, the hierarchical carbon-derived supercapacitor displayed excellent cycling stability at a current density of 1Ag−1 (about 93.5% retention after 10,000cycles), 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.