Method and apparatus for producing single-wall carbon nanotubes

Abstract

There is provided a method for producing single-wall carbon nanotubes comprising condensing a plasma comprising atoms or molecules of carbon and atoms of a metal suitable for catalyzing the formation of single-wall carbon nanotubes in an oven at a predetermined temperature so as to provide a temperature gradient, thereby forming single-wall carbon nanotubes; and collecting the so-formed single-wall carbon nanotubes by passing them through an electrostatic trap comprising a pair of electrodes generating an electrical current so as to deposit at least a portion of the single-wall carbon nanotubes on one of the electrodes.

1 - 36 . (canceled) 
     
     
         37 : A method for producing single-wall carbon nanotubes comprising,
 condensing a plasma comprising atoms or molecules of carbon and atoms of a metal suitable for catalyzing the formation of single-wall carbon nanotubes in an oven at a predetermined temperature so as to provide a temperature gradient, thereby forming single-wall carbon nanotubes; and   collecting the so-formed single-wall carbon nanotubes by passing them through an electrostatic trap comprising a pair of electrodes generating an electrical current so as to deposit at least a portion of said single-wall carbon nanotubes on one of said electrodes.   
     
     
         38 : The method of  claim 37 , wherein said metal is chosen from Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Y, La, Ce, Mn, Li, Pr, Nd, Tb, Dy, Ho, Er, Lu and Gd. 
     
     
         39 : The method of  claim 37 , wherein said metal is Fe. 
     
     
         40 : The method of  claim 37 , wherein said predetermined temperature is comprised between 500 and 1800° C. 
     
     
         41 : The method of  claim 40 , wherein said metal is Fe. 
     
     
         42 : The method of  claim 37 , wherein said predetermined temperature is comprised between 800 and 950° C. 
     
     
         43 : The method of  claim 42 , wherein said metal is Fe. 
     
     
         44 : In a method for producing single-wall carbon nanotubes with a plasma torch comprising feeding said plasma torch with an inert gas, a carbon-containing substance and a metal catalyst, the improvement wherein the single-wall carbon nanotubes are collected by means of an electrostatic trap disposed downstream of said plasma torch. 
     
     
         45 : The method of  claim 44 , wherein said electrostatic trap comprises a pair of electrodes generating an electrical current and at least a portion of said single-wall carbon nanotubes are deposited on one of said electrodes. 
     
     
         46 : The method of  claim 45 , wherein said single-wall carbon nanotubes are passed through an oven defining a temperature gradient before being deposited. 
     
     
         47 : The method of  claim 45 , wherein said carbon-containing substance is a carbon-containing solid or a carbon-containing gas. 
     
     
         48 : The method of  claim 45 , wherein said carbon-containing substance is a carbon-containing gas chosen from C 1 -C 4  hydrocarbons. 
     
     
         49 : The method of  claim 48 , wherein said metal is Fe. 
     
     
         50 : A method for collecting single-wall carbon nanotubes comprising contacting the single-wall carbon nanotubes with an electrostatic trap comprising a pair of electrodes generating an electrical current so as to deposit at least a portion of said single-wall carbon nanotubes on one of said electrodes. 
     
     
         51 : The method of  claim 50 , wherein said single-wall carbon nanotubes are generated by means of a plasma torch and wherein said electrostatic trap is disposed sufficiently downstream of said plasma torch so as to permit to the single-wall carbon nanotubes to be condensed according to a temperature gradient before being deposited. 
     
     
         52 : The method of  claim 51 , wherein said single-wall carbon nanotubes are produced by:
 feeding an inert gas through a plasma torch to form an inert gas plasma;   injecting a carbon-containing substance and a metal catalyst in said inert gas plasma downstream of said inert gas feed, in order to form a plasma comprising atoms or molecules of carbon and atoms of said metal; and   condensing said atoms or molecules of carbon and said atoms of said metal to form single-wall carbon nanotubes.   
     
     
         53 : The method of  claim 52 , wherein said carbon-containing substance is a carbon-containing solid or a carbon-containing gas. 
     
     
         54 : The method of  claim 52 , wherein said carbon-containing substance is a carbon-containing gas chosen from C 1 -C 4  hydrocarbons. 
     
     
         55 : The method of  claim 54 , wherein said metal is Fe. 
     
     
         56 : The method of  claim 55 , wherein said inert gas is argon.