Abstract Submitted to the NANOTUBE'02 Workshop:

Carbon nanotubes have been produced by a mechano-thermal process, consisting of mechanical milling of graphite powder at room temperature and subsequent thermal annealing at 1400 oC. The mechanical treatment of graphite powder produces a microporous and amorphous structure, corresponding to nucleation sites and an available source of free carbon atoms respectively. The subsequent low-temperature annealing activates growth of the (002) basal planes. We will show that the mechanical milling and thermal annealing actually correspond to separate nucleation and growth processes respectively. Metal catalysts play an important role on the formation of various nanostructures, but multi-walled nanotube can be produced without metal catalysts in the mechano-thermal process.