Nitrogen-doped multi-walled carbon nanotubes (CNTs) containing 2.2 at.% of nitrogen were produced by hydrothermal treatment of oxygen-doped CNTs with urea and tested as electrode material for the supercapacitor with ionic liquid electrolyte. Cyclic voltammetry measurements showed a beneficial effect of nitrogen doping on the capacitance behavior of CNTs resulted from both the changes in their electronic structure and improved interaction between the electrode surface and electrolyte ions. The specific capacitance of nitrogen-doped CNTs was 2.6 times higher than that of pristine ones.

中文翻译：

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氮氧掺杂多壁碳纳米管用于具有离子液体电解质的超级电容器

氮掺杂多壁碳纳米管 (CNTs) 含有 2.2 at.% 的氮，是通过用尿素水热处理氧掺杂的 CNT 来制备的，并作为具有离子液体电解质的超级电容器的电极材料进行了测试。循环伏安法测量表明，氮掺杂对 CNT 的电容行为产生了有益的影响，这是由于其电子结构的变化和电极表面与电解质离子之间的相互作用的改善所致。氮掺杂碳纳米管的比电容是原始碳纳米管的 2.6 倍。