Process for producing single wall nanotubes using unsupported metal catalysts and single wall nanotubes produced according to this method

• US 6,827,919 B1
• Filed: 06/29/2000
• Issued: 12/07/2004
• Est. Priority Date: 08/04/1997
• Status: Expired due to Fees

• Current Assignee: Hyperion Catalysis International Incorporated
• Original Assignee: Hyperion Catalysis International Incorporated
• Inventors: Moy, David, Chishti, Asif
• Primary Examiner(s): HENDRICKSON, STUART L
• Application Number:
  US09/607,126
• Time in Patent Office: 1,622 Days
• Field of Search: 423/447.3
• US Class Current: 423/447.3
• CPC Class Codes: B01J 19/121 Coherent waves, e.g. laser beams lasers per se H01S3/00
• CPC Class Codes: B01J 19/26 Nozzle-type reactors, i.e. the distribution of the initial reactants within the reactor is effected by their introduction or injection through nozzles
• CPC Class Codes: B01J 2219/0875 Gas
• CPC Class Codes: B01J 3/04 Pressure vessels, e.g. autoclaves
• CPC Class Codes: B01J 3/042 in the form of a tube
• 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
• CPC Class Codes: D01F 9/127 by thermal decomposition of hydrocarbon gases or vapours or other carbon-containing compounds in the form of gas or vapour, e.g. carbon monoxide, alcohols
• CPC Class Codes: D01F 9/1278 Carbon monoxide
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/75 Single-walled
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes
• CPC Class Codes: Y10S 977/843 Gas phase catalytic growth, i.e. chemical vapor deposition
• CPC Class Codes: Y10S 977/896 Chemical synthesis, e.g. chemical bonding or breaking

Abstract

A process for producing hollow, single-walled carbon nanotubes by catalytic decomposition of one or more gaseous carbon compounds by first forming a gas phase mixture carbon feed stock gas comprising one or more gaseous carbon compounds, each having one to six carbon atoms and only H, O, N, S or Cl as hetero atoms, optionally admixed with hydrogen, and a gas phase metal containing compound which is unstable under reaction conditions for said decomposition, and which forms a metal containing catalyst which acts as a decomposition catalyst under reaction conditions; and then conducting said decomposition reaction under decomposition reaction conditions, thereby producing said nanotubes.

Claims

1. A method for producing hollow, single-walled carbon nanotubes having diameters less than about 3 nanometers by catalytic decomposition of one or more gaseous carbon compounds comprising the steps of:

(1) forming a gas phase mixture of;

(a) a carbon feed stock gas comprising one or more gaseous carbon compounds, each said compound having one to six carbon atoms and only H, O, N, S or Cl as hetero atoms, optionally admixed with hydrogen, a diluent or mixtures thereof; and

(b) a gas phase metal containing compound which is unstable under reaction conditions for said catalytic decomposition, and which forms metal containing catalysts which act as decomposition catalysts under reaction conditions;

(2) and conducting said catalytic decomposition reaction under decomposition reaction conditions and thereby producing said hollow, single-walled carbon nanotubes having diameters less than about 3 nanometers.

3. The method as defined in claim 1, wherein said carbon feedstock gas comprises carbon monoxide.

4. The method as defined in claim 1, wherein said carbon feedstock gas consists essentially of carbon monoxide.

5. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 400°

C. and approximately 1300°

C.

6. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 400°

C. and approximately 1100°

C.

7. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 400°

C. and approximately 900°

C.

8. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 700°

C. and approximately 1300°

C.

9. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 700°

C. and approximately 1100°

C.

10. The method as defined in claim 1, wherein said decomposition reaction occurs at temperatures between approximately 700°

C. and approximately 900°

C.

11. The method as defined in claim 1, wherein said decomposition reaction occurs at a pressure range of approaching 0 p.s.i.g. through approximately 100 p.s.i.g.

12. The method as defined in claim 1, wherein said gas phase metal containing compound is mixed with said feedstock by direct injection.

13. The method as defined in claim 1, wherein said gas phase metal containing compound is in the form of an aerosol.

14. The method as defined in claim 1, wherein said gas phase metal containing compound is a metal carbonyl.

15. The method as defined in claim 1, wherein said gas phase metal containing compound comprises iron carbonyl.

16. The method as defined in claim 1, wherein said gas phase metal containing compound comprises molybdenum carbonyl.

17. The method as defined in claim 1, wherein said gas phase metal containing compound comprises cobalt carbonyl.

18. The method as defined in claim 1, wherein said gas phase metal containing compound is Mo(CO)₆.

19. The method as defined in claim 1, wherein said gas phase metal containing compound is CO₂(CO)₈.

20. The method as defined in claim 1, wherein said gas phase metal containing compound is a volatile iron compound.

21. The method as defined in claim 20, wherein said volatile iron compound is ferrocene.

22. The method as defined in claim 1, wherein said gas phase metal containing compound is a volatile manganese compound.

23. The method as defined in claim 22, wherein said volatile manganese compound is methylcyclopentadienyl manganese tricarbonyl.

24. The method as defined in claim 1, wherein said gas phase metal containing compound is a volatile cobalt compound.

25. The method as defined in claim 24, wherein said volatile cobalt compound is cyclopentadienyl cobalt dicarbonyl.

26. The method as defined in claim 1, wherein said gas phase mixture consists essentially of said carbon feed stock gas and said gas phase metal containing compound, optionally admixed with hydrogen, a diluent or mixtures thereof.

27. The method as defined in claim 1, wherein said carbon nanotubes have diameters ranging from about 1 to about 3 nanometers.

28. The method as defined in claim 1, wherein said process provides a yield of single-walled carbon nanotubes greater than about 20 wt %.

29. The method as defined in claim 1, wherein said process provides a yield of single-walled carbon nanotubes greater than about 50 wt %.

30. The method as defined in claim 1, wherein said metal containing catalysts have diameters ranging from 1-10 nm.

2. A method for producing hollow, single-walled carbon nanotubes having diameters less than about 3 nanometers comprising the steps of:

(1) forming a gas phase mixture of;

(a) a carbon feed stock gas comprising one or more gaseous carbon compounds, each said compound having one to six carbon atoms and only H, O, N, S or Cl as hetero atoms, optionally admixed with hydrogen, a diluent or mixtures thereof; and

(b) a gas phase metal containing compound which forms metal containing catalysts which act as decomposition catalysts under reaction conditions; and

(2) conducting a reaction under said reaction conditions and thereby producing said hollow, single-walled carbon nanotubes having diameters less than about 3 nanometers.