Abstract We report a novel, facile method for the synthesis of nitrogen doped porous carbon with three-dimensional interconnected porous framework by one-step pyrolysis of the mixture of agar, potassium citrate and urea. The optimized material possesses large specific surface area, interconnected porous framework and massive heteroatom functional groups. As an electrode material, it delivers a high specific capacity of 357 F g−1 at 1 A g−1, good rate performance (267 F g−1 at 50 A g−1) and good electrochemical stabilization (95.6% initial capacitance retained after 10,000 cycles) in 6 M KOH solution. Moreover, the as-prepared symmetric supercapacitor based on the NPC electrodes shows an energy density of 24.1 Wh Kg−1 between the voltage ranges of 0–1.8 V in 1 M Na2SO4 solution, comparable with most of reported carbon-based symmetric supercapacitors. More immortally, even at a high power density of 12.5 kW kg−1, it still remains an energy density of 12.5 Wh kg−1. Therefore, this paper provides a facile, sustainable method for the synthesis of heteroatom doped three-dimensional interconnected porous carbon materials for high performance supercapacitors.

中文翻译：

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一种合成具有高倍率性能和能量密度的用于超级电容器的氮掺杂多孔碳材料的新方法

摘要 我们报道了一种新型、简便的方法，通过琼脂、柠檬酸钾和尿素的混合物一步热解合成具有三维互连多孔骨架的氮掺杂多孔碳。优化后的材料具有大比表面积、相互连接的多孔骨架和大量杂原子官能团。作为电极材料，它在 1 A g-1 时具有 357 F g-1 的高比容量、良好的倍率性能（在 50 A g-1 时为 267 F g-1）和良好的电化学稳定性（保留了 95.6% 的初始电容10,000 次循环后）在 6 M KOH 溶液中。此外，所制备的基于 NPC 电极的对称超级电容器在 1 M Na2SO4 溶液中的 0-1.8 V 电压范围内显示出 24.1 Wh Kg-1 的能量密度，与大多数报道的碳基对称超级电容器相当。更不朽的是，即使在 12.5 kW kg-1 的高功率密度下，它仍然保持 12.5 Wh kg-1 的能量密度。因此，本文为用于高性能超级电容器的杂原子掺杂三维互连多孔碳材料的合成提供了一种简便、可持续的方法。