Abstract Because of the instability and uncontrollability of the nitrogen-containing precursor upon high-temperature carbonization, it is very hard to obtain nanocarbon with high nitrogen content over 10 atom% and controllable electrochemically-active nitrogen species. Herein, we report a role-divided templating/doping strategy for the fabrication of porous nanocarbon supercapacitor materials with all-electroactive nitrogen species and ultrahigh energy density based on MgO and g-C3N4, in which MgO first acts as a polymerization catalyst to form carbon source and then as template for porous structure, while the g-C3N4 acts as a single nitrogen source. Systematic investigations reveal that the carbonization temperature and the single g-C3N4 nitrogen source are vital to obtaining all-electroactive nitrogen species. The obtained nanocarbon (WNLC973-C1N5) owns a worm-nest-like morphology, high surface area and all-electrochemically-active nitrogen functionalities (21.3 atom%). The symmetric supercapacitor based on WNLC973-C1N5 achieves an energy density of 53.2 Wh/kg at a power density of 1000 W/kg, about four times bigger than that of normal carbon-based material. This work highlights the importance of the special nitrogen source to form the all-electrochemically-active nitrogen functionalities for high-performance energy materials and presents facile strategy to fabricate carbon-based materials for extensive applications, such as catalyst, adsorbent, catalyst support, energy material and so on.

中文翻译：

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用于高能量密度超级电容器的全电活性氮物种掺杂的虫巢状纳米碳的可控合成

摘要 由于含氮前驱体在高温碳化过程中的不稳定性和不可控性，很难获得含氮量超过10原子％和可控电化学活性氮物种的纳米碳。在此，我们报告了一种基于 MgO 和 g-C3N4 的具有全电活性氮物种和超高能量密度的多孔纳米碳超级电容器材料的分角色模板/掺杂策略，其中 MgO 首先充当聚合催化剂以形成碳源，然后作为多孔结构的模板，而 g-C3N4 作为单一的氮源。系统研究表明，碳化温度和单一 g-C3N4 氮源对于获得全电活性氮物种至关重要。获得的纳米碳（WNLC973-C1N5）具有虫巢状形态、高表面积和全电化学活性氮官能度（21.3原子％）。基于 WNLC973-C1N5 的对称超级电容器在 1000 W/kg 的功率密度下实现了 53.2 Wh/kg 的能量密度，大约是普通碳基材料的四倍。这项工作强调了特殊氮源对形成高性能能源材料的全电化学活性氮官能团的重要性，并提出了制造碳基材料的简便策略，用于广泛应用，如催化剂、吸附剂、催化剂载体、能源材料等。基于 WNLC973-C1N5 的对称超级电容器在 1000 W/kg 的功率密度下实现了 53.2 Wh/kg 的能量密度，大约是普通碳基材料的四倍。这项工作强调了特殊氮源对形成高性能能源材料的全电化学活性氮官能团的重要性，并提出了制造碳基材料的简便策略，用于广泛应用，如催化剂、吸附剂、催化剂载体、能源材料等。基于 WNLC973-C1N5 的对称超级电容器在 1000 W/kg 的功率密度下实现了 53.2 Wh/kg 的能量密度，大约是普通碳基材料的四倍。这项工作强调了特殊氮源对形成高性能能源材料的全电化学活性氮官能团的重要性，并提出了制造碳基材料的简便策略，用于广泛应用，如催化剂、吸附剂、催化剂载体、能源材料等。