Process and apparatus for producing single-walled carbon nanotube

• US 20060073275A1
• Filed: 12/26/2003
• Published: 04/06/2006
• Est. Priority Date: 12/27/2002
• Status: Abandoned Application

• Current Assignee: Shigeo Maruyama
• Original Assignee: Shigeo Maruyama
• Inventors: Maruyama, Shigeo, Chiashi, Shohei
• Application Number:
  US10/540,826
• Publication Number:
  US 20060073275A1
• Time in Patent Office: Days
• US Class Current: 427/248.100
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: C01B 2202/02 Single-walled nanotubes
• CPC Class Codes: C01B 32/162 characterised by catalysts

Abstract

A solution prepared by dissolving an organic metal compound in an organic solvent is sprayed from a pore nozzle into a pre-heating furnace of 50 to 600° C. in a reaction furnace in a rare gas atmosphere of 500 Torr or less by pressurizing with an inert gas; a mixed gas of the organic metal compound and the organic solvent which are pre-heated and vaporized is fed into a main heating furnace which is adjacent to the above pre-heating furnace and heated to 550 to 1000° C. in a rare gas atmosphere of 500 Torr or less; the organic metal compound is thermally decomposed to produce metal fine particles; the organic solvent is thermally decomposed with the above particles being used as a catalyst to produce carbon atoms; and a graphene sheet is grown in a growing part provided at a downstream side of the main heating furnace, whereby a single-walled carbon nanotube is prepared. Ferrocene and iron carbonyl can be used as the organic metal compound, and alcohols and ethers can be used as the organic solvent.

Claims

1. A process for producing a single-walled carbon nanotube by a vapor deposition technique, comprising:

a step of spraying a solution prepared by dissolving an organic metal compound in an organic solvent into a furnace of a rare gas atmosphere,

a step of vaporizing the organic metal compound and the organic solvent each described above by heating the sprayed solution,

a step of heating and decomposing the vaporized organic metal compound to obtain metal and heating and decomposing the vaporized organic solvent with the metal described above being used as a decomposition catalyst to obtain carbon atoms and

a step of growing a graphene sheet using the carbon atoms obtained.

2. The process for producing a single-walled carbon nanotube as described in claim 1, wherein a pressure in the furnace is controlled to 760 Torr or less.

3. The process for producing a single-walled carbon nanotube as described in claim 2, wherein a pressure in the furnace is controlled to 500 Torr or less.

4. The process for producing a single-walled carbon nanotube as described in claim 1, wherein the organic solvent is alcohol.

5. The process for producing a single-walled carbon nanotube as described in claim 4, wherein the alcohol is ethanol.

6. The process for producing a single-walled carbon nanotube as described in claim 1, wherein the organic metal compound is metallocene.

7. The process for producing a single-walled carbon nanotube as described in claim 6, wherein the metallocene is ferrocene.

8. The process for producing a single-walled carbon nanotube as described in claim 1, wherein the organic metal compound contained in the solution prepared by dissolving the organic metal compound in the organic solvent has a concentration of 0.01 to 1 mass %.

9. The process for producing a single-walled carbon nanotube as described in claim 1, wherein the solution described above which is pressurized by an inert gas having a back pressure of 100 to 1000 Torr is sprayed through a nozzle having an aperture diameter of 0.01 to 1 mm.

10. The process for producing a single-walled carbon nanotube as described in claim 1, wherein a heating temperature for vaporizing the organic solvent and the organic metal compound is 50 to 600°

C.

11. The process for producing a single-walled carbon nanotube as described in claim 10, wherein a heating temperature for vaporizing the organic solvent and the organic metal compound is 100 to 400°

C.

12. The process for producing a single-walled carbon nanotube as described in claim 10, wherein a heating temperature for heating and decomposing the organic solvent and the organic metal compound is 550 to 1000°

C.

13. The process for producing a single-walled carbon nanotube as described in claim 11, wherein a heating temperature for heating and decomposing the organic solvent and the organic metal compound is 700 to 1000°

C.

14. The process for producing a single-walled carbon nanotube as described in claim 12, wherein a temperature for growing the graphene sheet is lower than a temperature of heating the organic solvent.

15. The process for producing a single-walled carbon nanotube as described in claim 13, wherein a temperature for growing the grapheme sheet is lower than a temperature of heating the organic solvent.

16. The process for producing a single-walled carbon nanotube as described in claim 9, wherein the inert gas is argon or helium.

17. The process for producing a single-walled carbon nanotube as described in claim 9, wherein 5 mass % or less of hydrogen gas is mixed with the inert gas.

18. The process for producing a single-walled carbon nanotube as described in claim 1, wherein the single-walled carbon nanotube comprising the grown graphene sheet is collected by a membrane filter.

19. Equipment for producing a single-walled carbon nanotube by a vapor deposit technique, comprising:

a nozzle for spraying a solution prepared by dissolving an organic metal compound in an organic solvent by pressurizing with an inert gas having a prescribed back pressure,

a pre-heating part for vaporizing the organic metal compound and the organic solvent each described above by heating the sprayed solution,

a main heating and decomposing the organic metal compound vaporized in the pre-heating part and heating and decomposing the organic solvent vaporized in the pre-heating part with the metal obtained by heating and decomposing the organic metal compound being used as a catalyst,

a growing part for growing a graphene sheet using carbon atoms obtained by heating and decomposing the solvent described above in the main heating part,

a first controlling means for heating and maintaining a temperature of the furnace in the pre-heating part described above at 50 to 600°

C.,

a second controlling means for heating and maintaining a temperature of the furnace in the main heating part described above at 550 to 1000°

C. and

a third controlling means for maintaining the pre-heating part, the main heating part and the growing part in a rare gas atmosphere.