氮掺杂石墨烯/碳纳米管/无定形炭复合材料制备及其电化学性能

碳基复合材料被认为是超级电容器广泛应用最有前景的电极材料之一。本文使用氧化石墨烯（GO）、硝酸钴［Co(NO₃)₂］、三聚氰胺为原料，利用钴对高温下热解碳源的催化作用，制备得到了氮掺杂石墨烯/碳纳米管/无定形炭（NC）复合材料，并测试了其电化学性能。探究了金属和三聚氰胺添加量对碳基复合材料结构和性能的影响，研究发现，在添加量分别为0.02mmol和0.3g时，制得的样品具有大比表面积（380.5m²/g）和高掺氮质量分数（6.29%），并在三电极系统中体现出优异的电化学性能，电流密度为0.5A/g时样品的比电容为137.1F/g，5A/g时比电容为113.5F/g，保持率为88.5%，具有优异的倍率性能，在循环5000圈后样品的容量保持率为104%，具有良好的循环稳定性，这归因于三维结构可以加快充放电过程中的离子转移和氮掺杂可提高材料润湿性和贡献部分赝电容，为超级电容器电极材料的制备提供了理论借鉴。

Preparation and electrochemical properties of nitrogen-doped graphene/carbon nanotubes/amorphous carbon composites

Carbon matrix composites are considered to be one of the most promising electrode materials for the wide application of supercapacitors. In this paper, graphene oxide (GO), cobalt nitrate Co(NO₃)₂] and melamine were used to prepared nitrogen-doped graphene/carbon nanotubes/amorphous carbon (NC) composites which by using the catalytic action of cobalt on pyrolytic carbon source at high temperature, and then NC electrochemical properties were tested. The effects of metal and melamine addition levels on the structure and properties of carbon matrix composites were investigated. It was found that when the addition levels were 0.02mmol and 0.3g, respectively, the prepared materials had large specific surface area (380.5m²/g) and nitrogen content (6.29%). When the current density was 0.5A/g, the material specific capacitance was 137.1F/g, respectively with and when the current density is 5A/g, the specific capacitance was 113.5F/g, and the retention rate was 88.5%, showing excellent rate performance. After 5000 cycles, the capacity retention rate of the material was 104%, indicating good cycle stability. It was attributed to the fact that the three-dimensional structure can accelerate the ion transfer and nitrogen doping during charge and discharge processes, which can improve the material wettability and contribute part of pseudo capacitance, providing theoretical reference for the preparation of electrode materials for supercapacitors.