减压化学气相沉积法制备规则螺旋状纳米碳管

以硅胶负载的Co纳米颗粒为催化剂,在低流量的减压体系中通过化学气相沉积法制备了规则螺旋状的纳米碳管.通过TEM和HRTEM研究了螺旋碳管的形貌、尺度分布以及管身、曲面和节点处的晶型;讨论了催化剂制备中pH值对催化剂的尺寸、规则程度和存在形态以致对螺旋碳管产量、管径厚度以及螺旋管的相对比例的影响;此外,还分析了反应压力对碳管生长的影响.

Preparation of Regular Coiled Carbon Nanotubes by Reduced-pressure Catalytic Chemical Vapor Deposition

Regular coiled carbon nanotubes were prepared by catalytic chemical vapor deposition(CCVD) on finely divided Co nano-particles supported on silica gel at reduced pressure and lower gas flow rates. The morphology and the distribution of the geometrical parameters of the coiled carbon nanotubes were examined by TEM,while the graphitization of coil tube,coil bend and coil node were analyzed by HRTEM. The influences of the pH values and the reaction pressure on the growth of the coiled carbon nanotubes were also discussed. With this modified CCVD approach,the amorphous carbon generally coated on the carbon nanotubes was greatly decreased.