Self-supported Carbon Nanotubes through Constraint Synthesis

1 Self-supported Carbon Nanotubes through Constraint Synthesis 

In the case of constraint synthesis the catalyst consisted of 20wt.%Fe/Al2O3, deposited inside a tubular reactor, where the two ends were closed with a permeable carbon felt allowing the gaseous reactants to pass through the reactor channel 

2 Parallel and Patterned Carbon Nanotubes by Pyrolysis of Organic Compounds 

The synthesis of the patterned macroscopic shape consists in the growth of carbon nanotubes in a parallel direction from a fiat substrate surface. This was achieved using a mixture of toluene containing ferrocene compounds or directly with ethylene and steam etching [46-49]. The carbon nanotubes were formed as a thick layer covering the silica reactor wall. The sample could easily be recovered by scratching the dark deposit with a razor blade. 

In Fig. 7.6 are presented the typical SEM images with different magnifications of the carbon nanotubes forest generated via the pyrolysis of ferrocene in a toluene flow reahzed in the laboratory. 

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