| 摘要 |
Continuous nanotube synthesis by vortex deposition occurs in an axially-fed shear reactor comprising coaxial counter-rotating disk impeller/electrodes charged as anodes. Nanotube evolving ends, charged as cathodes, point toward the anode axis of rotation and protrude into the space between the anodes. Radial vortices in a shear layer of the space, between the boundary layers on the impeller/electrodes, spin cations to be deposited on evolving nanotube ends approximately at the vortex axis, so deposition is by swirling cathode fall. The evolved nanotubes are extracted mechanically, and they conduct electrons from charging means to charge the evolving ends as cathodes. The preferential synthesis of metallic carbon nanotubes is due to the greater resistance of non-metallic structures such as graphite or semiconductive structures. Ozone serves to oxidize non-metallic structures and to functionalize the loose ends of nanotube fragments. Dopants can be added to the evolving nanotubes by introduction of dopants at the periphery because the evolving ends are maintained in stable locations. Or dopants can be added by the simultaneous decomposition of gases (for example, carbon dioxide and nitrogen gas) within the reactor or in an external reactor.
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