Pyrolytic production of aligned carbon nanotubes from homogeneously dispersed benzene-based aerosols

Aligned multi-walled carbon nanotubes (30–130 μm long, 10–200 nm outer diameter) have been prepared in high yield by pyrolysing homogeneously dispersed aerosols generated from benzene/ferrocene solutions, at 800°C or 950°C, using a compressed gas (Ar) driven atomiser. Scanning electron microscopy (SEM) and TEM studies reveal the presence of carpet-like flakes containing high yields of partly filled carbon nanotubes. X-ray diffraction confirms the presence of graphite-like structures, α-Fe and Fe3C (cementite). Nanotube and filling yields were found to be temperature and ferrocene concentration dependent. The preparative method opens up new avenues for nanotube synthesis based upon hydrocarbon/catalyst solutions.