| abstract |
The present invention relates to a catalytic precursor gas (e.g. Fe (CO)) in preheated (e.g., about 1000 ° C) high pressure (e.g., 30 atmospheres) carbon monoxide and carbon monoxide maintained below the temperature at which the catalyst precursor decomposes. 5 ) to a mixed band. In the mixing zone, the catalyst precursor is rapidly heated to a temperature that (1) decomposes the precursor, (2) forms an active catalyst rapid atom cluster of suitable size, and (3) preferably grows SWNTs on the catalyst cluster. . Catalyst cluster nucleation means can be used to rapidly react the catalyst precursor gas to form a large number of small, active catalyst particles instead of a few large, inert catalyst particles. Such nucleation means may include auxiliary metal precursors that form clusters more rapidly than primary catalysts, and when additional energy is introduced (e.g., from pulse or CW lasers), they form precisely in the zone where cluster formation is needed. do. Under these conditions, SWNTs grow and form nuclei following the Boudard reaction. The SWNTs thus formed can either be recovered directly or pass through growth and annealing zones maintained at high temperatures (eg 1000 ° C.) where the tubes can continue to grow and coalesce in rope form. |