We treated carbon nanotubes (CNTs) with hydrazine hydrate and diethylenetriamine separately and characterized them using scanning electron spectroscopy (SEM) and X-ray photoelectron spectroscopy (XPS).SEM indicated that the treated CNTs retained the length/diameter ratio of the pure CNTs and XPS showed that nitrogen was doped in the CNTs.XPS analysis also indicated that the carbon/nitrogen atomic ratio of the CNTs treated by hydrazine hydrate was 95/2, which was much higher than the 96/0.5 for the CNTs treated by diethylenetriamine.The hydrophilicity of the CNTs was found to be much higher after N-doping and it increased with an increase in the N content.Therefore, the water dispersibility of the N-doped CNTs treated by hydrazine hydrate was better than that of the N-doped CNTs treated by diethylenetriamine.As electrode materials for electrochemical capacitors, nitrogen functional groups contribute to the pseudo-Faradic capacitance but their cyclic performance still needs to be improved.Because of the good hydrophilicity of the N-doping CNTs, which improves the wettability of the CNTs for the electrolyte, the specific capacitance of the N-doping CNT electrode is still slightly higher than that of the pure CNT electrode after cycling.%采用弱反应性含氮有机物水合肼、二乙烯三胺对碳纳米管进行氮掺杂处理.结合X射线光电子谱(XPS)分析和扫描电镜(SEM)观察,发现两种含氮有机物处理均可使碳纳米管表面成功连接上含氮基团,并保持了碳纳米管的本征形貌和结构.水合肼处理的碳纳米管的氮含量(碳/氮原子比为95/2)明显高于二乙烯三胺处理的碳纳米管(碳/氮原子比为96,0.5).氮掺杂后碳纳米管在水溶液中分散性明显改善,且分散性随着氮含量增加进一步增强,因此水合肼处理的碳纳米管分散性明显优于二乙烯三胺处理的碳纳米管.作为电化学电容器电极材料,碳纳米管含氮官能团贡献了赝电容,但其循环性仍需进一步改进,氮掺杂碳纳米管较好的亲水性,改善了电解液的浸润,循环后氮掺杂碳纳米管电极的比容量仍略高于纯碳纳米管电极的比容量.
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