摘要
以苯和甲苯为碳源,二茂铁为催化剂前驱体,含硫化合物为助催化剂,采用竖式炉流动催化法,通过减小载入的氢气量以改变催化剂颗粒的状态及反应条件,获得了碳包铁颗粒以及放射状碳纳米管,运用TEM和HRTEM对其形貌和结构进行了分析,并初步探讨了其生长机理。结果表明,在碳源、催化剂和炉温分布相同的条件下,氢气量为5400mL/min时形成直线型和弯曲型两种不同形态的碳纳米管,后者管径大于前者。氢气量为2000mL/min时,产物90％以上为碳包铁颗粒,其平均直径约为530nm,其中还有少量放射状碳纳米管,其外径为45～50nm,内径为3～5nm,管径较为均匀。
Using benzene and toluene as carbon source, ferrocene as catalyst with a kind of sulphur compound as promoter, carbon-coated-iron particles and radially-grown carbon nanotubes were prepared by the catalytic pyrolysis method,and the effect of the flow rate of H2 on the growth of the products was studied. The morphology and structure of the carbon-coated particles and carbon nanotubes were examined by TEM and HRTEM, and the growth mechanism of these nanomaterials was discussed. The results show that under the same conditions (carbon source, catalyst and temperature), two types of carbon nanotubes, straight and non-straight, are synthesized with the flow rate of H2 being 5 400 mL/min. The inner diameter of the straight nanotubes is larger than that of the non-straight ones. When the flow rate of H2 is 2 000 mL/min, about 90% of the products are the carbon-coated iron particles with an average size of about 530 nm. Other products are some radially-grown carbon nanotubes with outer diameter of 45-50 nm and inner diameter of 3-5 nm.
出处
《炭素技术》
CAS
CSCD
2003年第2期5-9,共5页
Carbon Techniques
基金
九五军工配套项目
关键词
催化热解法
碳包铁颗粒
放射状碳纳米管
生长机理
Catalytic pyrdysis method
carbon-coated iron partide
radially-grown carbon nanotubes
growth mechanism
