Selective Co-catalysed growth of novel MgO fishbone fractal nanostructures

Novel MgO fishbone- or fern-like nanostructures, and Al2O3 fibre networks, have been generated for the first time from an Al2O3 matrix containing MgO and SiO2. The significance of the selective Co-catalysed growth of the elegant three-dimensional fractal fishbones is discussed. We have adopted the vapour-liquid-solid (V-L-S) and nucleation-aggregation (N-A) mechanisms, which take effect equally during the heating process, to account for the formation of these uniquely stacked fractal structures. (C) 2001 Elsevier Science B.V. All rights reserved.</p

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

Camphor-based carbon nanotubes as an anode in lithium secondary batteries

Camphor vapour is pyrolysed in the presence of Fe, Ni and Co powder under a dinitrogen atmosphere at different temperatures (750-1050 degreesC). While Fe and Ni catalyse the formation of carbon nanotubes (CNs), Co facilitates carbon nanobead growth. The CNs, obtained using a Fe catalyst at 950 degreesC, are utilised as the anode in Li secondary batteries. The capacity of the batteries constructed in this way is as good as those prepared by graphitic carbon formed in the arc process. (C) 2002

New advances in the creation of nanostructured materials

New advances have been made in the creation of nanostructured materials by pyrolytic and electrolytic methods. These experiments have shown that a wide range of nanostructures can be made using imaginative approaches