Abstract Submitted to the NANOTUBE'02 Workshop:

Multi-walled carbon nanotubes(MWCNTs) were produced by CVD approach. Propylene was used as carbon source material, and ferrocene as catalyst. The reaction was carried out in a new-style Nano-Agglomerate Reactor. Ferrocene dissolved in benzene was vaporized and fed into reactor by nitrogen. As-prepared CNTs by nickel catalyst were used as substrate to provide initial reaction interface. Ferrocene contacting with CNTs, the nanosized Fe particles from pyrolysis of ferrocene become active sites attaching on CNTs and the CNTs act as support, which results in growth of branch CNTs on CNTs support. The TEM images reveal thinner nanotubes, with diameter of several nanometers and tens of nanometer in length, can grow on CNTs support with diameter of about 10 nm. And the branches tend to grow around some active sites that can be both on CNTs ends and side-walls, to form a “tree-like” structure. A new growing-mode of CNTs was proposed to explain this kind of structure. The TEM and SEM images also reveal that the as-grown CNTs are wrapped and short relatively, with aspect ratio of even less than 10. According to TGA, the purity of as-grown CNTs is high to 90%.