Zhao Zhenyu, Xiao Zuoyi, Xi Yaru, Wang Guoxiang, Zhang Youchen, Li Jiajun, Wei Li
Liaoning Key Laboratory of Lignocellulosic Chemistry and Biomaterials, College of Light Industry and Chemical Engineering, Dalian Polytechnic University, Dalian 116034, China.
Inorg Chem. 2021 Sep 6;60(17):13252-13261. doi: 10.1021/acs.inorgchem.1c01617. Epub 2021 Aug 5.
Manufacturing heteroatom-doped porous C with controllable N species is an important issue for supercapacitors. Herein, we report a low-cost and simplified strategy for synthesizing B,N-codoped porous C (BNPC) by a freeze-drying chitosan-boric acid aerogel beads and subsequent carbonization treatment. The BNPC samples were studied using various characterization technologies. The introduction of boric acid to chitosan successfully induced the formation of B,N-codoped C with a well-developed 3D interconnected porous structure. The B doping had a significant impact on the distribution of N species in the samples. Moreover, the good wettability of the sample resulting from B doping is favorable for electrolyte diffusion and ion transport. As a consequence, the optimal BNPC sample showed an excellent specific capacitance of 240 F g at 0.5 A g and an outstanding capacitance retention of 95.1% after 10000 cycles at 5 A g. An assembled symmetrical supercapacitor displayed an energy density of 11.4 Wh kg at a power density of 250 W kg. The proposed work provides a simple and effective method to obtain B,N-codoped C-based materials with high electrochemical performance.
制造具有可控氮物种的杂原子掺杂多孔碳是超级电容器领域的一个重要问题。在此，我们报道了一种低成本且简化的策略，通过冷冻干燥壳聚糖 - 硼酸气凝胶珠并随后进行碳化处理来合成硼、氮共掺杂多孔碳（BNPC）。使用各种表征技术对BNPC样品进行了研究。将硼酸引入壳聚糖成功诱导形成了具有发达三维互连多孔结构的硼、氮共掺杂碳。硼掺杂对样品中氮物种的分布有显著影响。此外，硼掺杂导致样品具有良好的润湿性，有利于电解质扩散和离子传输。因此，最优的BNPC样品在0.5 A g时表现出240 F g的优异比电容，在5 A g下循环10000次后电容保持率高达95.1%。组装的对称超级电容器在功率密度为250 W kg时能量密度为11.4 Wh kg。本工作提供了一种简单有效的方法来获得具有高电化学性能的硼、氮共掺杂碳基材料。
