Nitrogen-doped porous carbon materials derived from ionic liquids as electrode for supercapacitor

摘要

Nitrogen-doped porous carbon materials (NPCs) were successfully obtained through one-step carbonization of an ionic liquid, that is, 1-ethyl-3-methylimidazolium dicyanamide (EMIM-dca), adopting eutectic salt (ZnCl2-NaCl) as the porogen agent. The nitrogen content and textural structure of the obtained carbon materials are highly dependent on the dosage of salt. The as-prepared NPCs integrate the superiorities of reasonable pore structure, high nitrogen content as well as homogeneous distribution, and high surface area. When served as electrodes for supercapacitor, a typical NPC-2 electrode exhibits a high specific capacitance of 335.3 and 206 F g(-1) at current densities of 0.5 and 10 A g(-1), respectively, considerable energy density (up to 10.1 Wh kg(-1)), and excellent cycling stability with almost no degradation over 10,000 cycles in KOH aqueous solution.