Fishbone-derived N-doped hierarchical porous carbon as an electrode material for supercapacitor

A cost-effective and sustainable approach has been developed to synthesize N-doped carbon material from fishbone waste via a one-step carbonization without an addition of chemical activator as a catalyst. The carbonization temperature can be optimized so that a favorable layered structure is achieved in 3D-flake nitrogen-doped hierarchical porous carbon (NPC). NPC-850 (NPC that was carbonized at 850 degrees C) not only has a high specific surface area of up to 1337 m(2) g(-1), but is also richly doped with heteroatoms (N and O content of 5.8 and 7.99 at.%, respectively). NPC-850 also exhibits an excellent electrochemical supercapacitor (SC) performance, i.e., a maximum specific capacitance of 476 F g(-1) in a three-electrode system and 354 F g(-1) in a symmetrical SC (both in a 1 M H2SO4), and a maximum energy density of 21.2 Wh kg(-1) in a symmetrical SC (in a 1 M TEABF(4)/AN). Moreover, NPC-850 can achieve high cycling stability, with 90.9% retaining of the original capacitance after 10,000 continuous cycles at a 1 A g(-1) current density. Such an outstanding performance suggests that our facile and scalable synthesis technique is effective to prepare porous carbon from biomass for electrochemical energy storage. (c) 2020 Elsevier B.V. All rights reserved.