为了拓展石墨烯凝胶在超级电容器方面的应用,采用氨水与水合肼作为掺杂剂和还原剂,通过与氧化石墨烯的水热反应制备了氮掺杂石墨烯凝胶,并进一步运用原位聚合的方法在氮掺杂石墨烯凝胶上负载聚苯胺,得到氮掺杂石墨烯/聚苯胺复合凝胶.利用X射线衍射、扫描电子显微镜对产物的结构和微观形貌进行表征,采用循环伏安、恒电流充放电等方法测试其电化学性能.结果表明,氮掺杂石墨烯/聚苯胺复合凝胶与纯氮掺杂石墨烯凝胶相比,电化学性能有显著的提高.当扫描速率为10 mV/s时,复合凝胶的比电容约为500 F/g;在恒电流充放电实验中,当电流密度增加到10 A/g时,复合凝胶的比电容仍然保持在约400 F/g.当循环伏安扫描1000圈后,比电容的保持率达到80%.这些表明氮掺杂石墨烯/聚苯胺复合凝胶拥有突出的电化学性能,也表明了氮掺杂石墨烯/聚苯胺在超级电容器方面将会有很好的应用前景.%For the development of graphene hydrogel in supercapacitors,nitrogen-doped graphene hydrogels were first prepared by the hydrothermal method using ammonia and hydrazine hydrate as the nitrogen resource and reducing agent,respectively. Then,the nitrogen-doped grapheme/polyaniline composite hydrogels were synthesized by in-situ polymerization of aniline monomer into nitrogen-doped grapheme hydrogel. X-ray diffraction and scanning electron microscopy were used to characterize the structure and microstructure of the products. The electrochemical performances were tested by cyclic voltammetry and galvanostatic charge-discharge. The results show that nitrogen-doped graphene/polyaniline composite hydrogel possesses better electrochemical performance than pure nitrogen-doped graphene gel. The specific capacitance of nitrogen-doped graphene hydrogel is about 500 F/g at the scanning rate of 10 mV/s. It keeps about 400 F/g at current density of 10 A/g in the galvanostatic charge-discharge test. Nitrogen-doped graphene/polyaniline composite hydrogel retains more than 80% of its initial specific capacitance after 1000 cycles of cyclic voltammetry. It indicates that nitrogen-doped graphene/polyaniline composite hydrogel has good electrochemical properties for the application of supercapacitor electrode in the future.
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