Strategies for the Rational Synthesis of Carbon Nanotubes

If the directed preparation of specific single-waUed carbon nanotubes succeeded, a mulhtude of studies would become possible regarding properties which, for the time being, are hardly or insufficiently accessible to examination. Moreover developmental materials for appHcations inevitably requiring a certain geometry of the tube would become available. 

To the present day, however, a rational synthesis of SWNT regrettably has not been realized, yet there are a number of approaches that shall be presented here. As for the first method, it is not a rational synthesis in the true sense of the meaning. Still, the pyrolytic decomposition of the cobaltocarbonyl complex 

The choice of the organic starting component largely influences the kind of carbon species generated. This becomes evident, for example, in the pyrolysis of metal complexes of some dehydro[n]annulenes Apart from the desired nanotubes, a series of other structures like carbon onions, graphite, or amorphous carbon is observed. 

The template-directed synthesis of nanotubes represents another approach. Suitable precursors (hydrocarbons, polyaromatic compounds, fullerenes, or other nanoscale carbon particles) may be subjected to pyrolysis while situated in pores 

SEM-image of a zeolitic template with protmding ends of nanotubes. The matrix has partly 

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