基于三元金属催化剂制备碳纳米管/三维石墨烯复合材料及电容性能

通过均匀沉淀法合成Ni-Mg-Al三元金属氧化物（TMO），再通过一步化学气相沉积法（CVD）以CH₄为碳源、Ar为保护性气体，在原位还原的Ni上生长碳纳米管（CNTs），在Mg和Al的金属氧化物上生长石墨烯（GR），利用水热法刻蚀掉TMO，制备CNTs/三维石墨烯（3DGR）复合材料。基于CNTs与GR两种组分生长动力学的差异，通过控制Ni、Mg和Al三种金属离子的摩尔比、生长温度、生长时间，调控和优化CNTs/3DGR复合材料的结构及电容性能。借助TEM、SEM、EDS、Raman和XRD对CNTs/3DGR复合材料的结构、形貌、组分进行表征。结果表明，CNTs与GR协同作用为CNTs/3DGR复合材料提供了更多电子运输通道，可大幅提高导电性能，实现电容性能的提升，CNTs/3DGR复合材料的比电容最高可达20 F/g。 

Preparation and capacitance performance of CNTs/3D graphene composites based on ternary catalysts

The ternary metallic Ni-Mg-Al oxide (TMO) was synthesized by a homogeneous precipitation method. The carbon nanotubes/3D graphene composites (CNTs/3DGR) were synthesized on the TMO by chemical vapor deposition(CVD) method using CH₄ as carbon source and Ar as protective gas. Herein, CNTs were grown on the in-situ reduced Ni nanoparticles, and the 3DGR was grown over the metallic composite oxides of Mg and Al. After etching the metal oxides, the CNTs/3DGR composite was obtained. The structure and performance of CNTs/3DGR were optimized by controlling the parameters during the precipitation of TMO and the CVD reaction of CNTs/3DGR, such as the metal ion molar ratio, growth temperature and growth time. TEM, SEM, EDS, Raman and XRD were employed to demonstrate the structure, morphology and composition of CNTs/3DGR composite. The results support that the synergistic roles of CNTs and GR contribute to give more paves for the electron transport, which promotes the electronic conductivity to improve the capacitance performance significantly with a specific capacitance of 20 F/g.