Synthesis and Morphology Evolution of Ultrahigh Content Nitrogen-Doped, Micropore-Dominated Carbon Materials as High-Performance Supercapacitors.

Nitrogen-doped carbon-based materials including nanocarbons, graphene, and conductive polymers are impressive as supercapacitor electrodes. However, ultrahigh nitrogen contents, micropore dominated, and morphology evolving carbonaceous electrodes have not achieved until now which are crucial for supercapacitor. Herein, we prepare a novel fumaronitrile (FUM) derived covalent triazine framework (FUM-CTF) and activated it by using KOH at different temperatures to obtain the corresponding carbon materials, which were used as supercapacitor electrode materials. Specially, the FUM-700 (sample activated at 700 °C) possesses an excellent specific capacitance of 400 F g-1 at a current density of 1 A g-1 and considerable energy density over 18 Wh kg-1 in KOH (6 m) aqueous electrolyte. In addition, this electrode shows 260 F g-1 at a current density of 20 A g-1 for charge/discharge operation. Furthermore, the FUM-700 electrode demonstrates extraordinary electrochemical stability with 97 % retention after 10 000 cycles at 10 A g-1 . Ultrahigh nitrogen contents, the microporous structure, and the inner nanoparticle morphology work in concert to contribute to the superior electrochemical performance of FUM-700. Our work might give some hints to help design other high-performance nitrogen-containing supercapacitor electrode materials.