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Single-walled carbon nanotubes (SWNTs) have been synthesized by the rapid injection of a nickel formate/silica gel catalyst/support into a hot fluidized-bed reactor. The initial rapid heating of the catalyst in the hydrocarbon feedstock was found to be essential for the nucleation of SWNTs since only amorphous or graphitic carbon particles were formed without it. These results suggest that the rapid heating of the catalyst precursor enables the formation of the small metal particles required for SWNT growth, probably due to the accelerated thermal decomposition of the catalyst precursor and enhanced nucleation rate. The growth of the SWNTs was investigated by the adoption of different methods for introducing the catalyst, and by varying the synthesis parameters including the catalyst loading, hydrocarbon gas flow rate, and concentration. The results found that SWNTs formed only under certain reaction conditions. The nanotubes produced were characterized by electron microscopy and Raman spectroscopy.

A novel method is presented to synthesize herringbone-stacked carbon nanofibers in high selectivity using cobaltocene as the catalytic precursor. Thiophene was essential for carbon nanofiber growth while hydrogen was used as the carrier gas. Selectivity close to 100% was achieved using cobaltocene, thiophene, and hydrogen reacted at 1100 °C. The conversion rate of the nanofibers collected in the cold trap was approximately 1.5 wt % of the initial products. The effect of the catalytic precursor temperature, thiophene, and acetylene was investigated, with reference to nanofiber diameter and selectivity.

The morphological and structural features of WS₂ nanotubes, generated from WO_x (x ≅ 2.7) needles, by an in-situ heating process, have been studied by electron microscopy and X-ray diffraction (XRD), in conjunction with computer simulation. The results show that these inorganic fullerene nanotubes exhibit interesting differences when compared with carbon nanotubes (CNTs). In some cases the tube tips or segments are open. Occasionally the tube walls may be uneven. The sulfur distribution within the tubes is uniform, except for the edge layers which appear to contain less sulfur. Defects are often observed, particularly in the outer shells, which may be due to defective encapsulated WO_x phases. Octagonal and square-like defects appear to be associated with the closure of tube caps. Electron diffraction (ED) reveals that nearly half of the non-helical WS₂ nanotubes are of the armchair-type. A mechanism has been proposed to account for the extended inorganic nanotube growth.

We describe the formation of novel, leaf-like Mg2SiO4structures, viaiodine vapour transport of magnesium onto quartz substrates.

We describe the formation of novel, leaf-like Mg₂SiO₄ structures, via iodine vapour transport of magnesium onto quartz substrates.