Method of making ropes of single-wall carbon nanotubes

• US 6,183,714 B1
• Filed: 07/26/1996
• Issued: 02/06/2001
• Est. Priority Date: 09/08/1995
• Status: Expired due to Term

• Current Assignee: Rice University
• Original Assignee: Rice University
• Inventors: Thess, Andreas, Guo, Ting, Smalley, Richard E., Rinzler, Andrew G., Nikolaev, Pavel, Colbert, Daniel T.
• Primary Examiner(s): Griffin, Steven P.
• Assistant Examiner(s): DI MAURO, PETER T
• Application Number:
  US08/687,665
• Time in Patent Office: 1,656 Days
• Field of Search: 423/445.B, 423/447.2, 423/447.3, 428/367
• US Class Current: 423/447.3
• CPC Class Codes: B82Y 15/00 Nanotechnology for interacting, sensing or actuating, e.g. quantum dots as markers in protein assays or molecular motors
• 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: Y02P 20/133 Renewable energy sources, e.g. sunlight
• CPC Class Codes: Y10S 977/844 Growth by vaporization or dissociation of carbon source using a high-energy heat source, e.g. electric arc, laser, plasma, e-beam
• CPC Class Codes: Y10T 428/2918 including free carbon or carbide or therewith [not as steel]

Abstract

This invention provides a method of making single-wall carbon nanotubes by laser vaporizing a mixture of carbon and one or more Group VIII transition metals. Single-wall carbon nanotubes preferentially form in the vapor and the one or more Group VIII transition metals catalyzed growth of the single-wall carbon nanotubes. In one embodiment of the invention, one or more single-wall carbon nanotubes are fixed in a high temperature zone so that the one or more Group VIII transition metals catalyze further growth of the single-wall carbon nanotube that is maintained in the high temperature zone. In another embodiment, two separate laser pulses are utilized with the second pulse timed to be absorbed by the vapor created by the first pulse.

Claims

1. A method of making single-wall carbon nanotubes which comprises:

(a) making a vapor comprising carbon and one or more Group VIII transition metals by vaporizing a mixture of carbon and one or more Group VIII transition metals with a first laser pulse;

(b) condensing the vapor to form a single-wall carbon nanotube having a live end; and

(c) supplying carbon vapor to the live end of the single-wall carbon nanotube while maintaining the live end of the single-wall carbon nanotube in an annealing zone, wherein ropes of single-wall carbon nanotubes are formed.

2. A method in accordance with claim 1 wherein the one or more Group VIII transition metals are selected from the group consisting of cobalt, ruthenium, nickel and platinum.

3. A method in accordance with claim 1 wherein the step of making a vapor comprising carbon and one or more Group VIII transition metals further comprises a second laser pulse timed to arrive after the finish of the first pulse and before the vapor made by the first laser pulse has dissipated and focused so that the energy from the second laser pulse is absorbed by the vapor.

38. A method in accordance with any one of claims 1, 4, 8, 15, or 22, wherein at least 10% of said single-wall carbon nanotubes are of the armchair (n, n) form.

39. A method in accordance with claim 38 wherein said nanotubes are of the (10, 10) form.

40. A method in accordance with any one of claims 1, 4, 8, 15, or 22, wherein at least 50% of said single-wall carbon nanotubes are of the armchair (n, n) form.

41. A method in accordance with claim 40 wherein said nanotubes are of the (10, 10) form.

42. A method in accordance with any one of claims 1, 4, 8, 15, or 22, wherein at least 75% of said single-wall carbon nanotubes are of the armchair (n, n) form.

43. A method in accordance with claim 42 wherein said nanotubes are of the (10, 10) form.

44. A method in accordance with any one of claims 1, 4, 8, 15, or 22, wherein at least 90% of said single-wall carbon nanotubes are of the armchair (n, n) form.

45. A method in accordance with claim 44 wherein said nanotubes are of the (10, 10) form.

46. A method in accordance with claim 1, wherein the carbon vapor of step (c) is derived from a hydrocarbon.

47. The method of any one of claims 1, 15 or 22, wherein the vapor of step (a) contains at least two Group VIII metals.

48. The method of claim 47, wherein the two Group VIII metals are cobalt and nickel.

4. A method of making single-wall carbon nanotubes which comprises:

vaporizing carbon and one or more Group VIII transition metals with a laser, transporting the vapor so formed through an annealing zone, condensing the vapor, and recovering single-wall carbon nanotubes from the material that condenses from the vapor, wherein at least a portion of said single-wall carbon nanotubes are in the form of ropes.

5. A method in accordance with claim 4 wherein the one or more Group VIII transition metals are selected from the group consisting of iron, cobalt, ruthenium, nickel and platinum.

6. A method in accordance with claim 5 wherein the carbon and one or more Group VIII transition metals are mixed together to form a target that is struck by a laser beam to produce the vapor.

7. A method in accordance with claim 6 wherein the carbon target is maintained in an annealing zone.

8. A method of making carbon nanotubes which comprises:

(a) making a vapor comprising carbon by using a first laser pulse to ablate material from a target comprising carbon and then using a second laser pulse timed to arrive at the target after the end of the first laser pulse and before the material ablated by the first laser pulse has dissipated and focused so that the energy from the second laser pulse is absorbed by the material ablated from the target by the first laser pulse to form a vapor; and

(b) condensing the vapor to form carbon nanotubes, wherein at least a portion of said carbon nanotubes are single-wall carbon nanotubes in the form of ropes.

9. A method in accordance with claim 8 wherein the second laser pulse arrives at the target within a delay of from about 20 nanoseconds (ns) to about 60 ns after the end of the first laser beam.

10. A method in accordance with claim 9 wherein the target further comprises one or more Group VIII transition metals.

11. A method in accordance with claim 10 wherein the one or more Group VIII transition metals are selected from the group consisting of iron, cobalt, ruthenium, nickel, and platinum.

12. A method in accordance with claim 11 wherein the vapor is condensed to form single-wall carbon nanotubes having a live end.

13. A method in accordance with claim 12 which further comprises maintaining the live end of the single-wall carbon nanotube in an annealing zone and supplying carbon vapor to the live end of the single-wall carbon nanotube.

14. A method in accordance with claim 13 wherein the delay is from about 40 ns to about 50 ns.

32. A method in accordance with any one of claims 2, 7, 13, 15, 22, or 30 wherein the annealing zone is maintained at a temperature of from about 1000°

C. to about 1400°

C.; and

the pressure in the annealing zone is maintained at about 100 to about 800 Torr.

33. A method in accordance with any one of claims 2, 7, 13, 15, 22, or 30 wherein the annealing zone is maintained in an atmosphere comprising carbon, and a gas selected from the group consisting of argon, neon, helium, carbon monoxide and mixtures thereof.

35. A method in accordance with any one of claims 13 or 22 wherein the target comprises about 0.1 atom percent to about 10 atom percent of one or more Group VIII transition metals selected from the group consisting of iron, cobalt, ruthenium, nickel and platinum.

15. A method of making ropes of metallic single-wall carbon nanotubes comprising:

(a) vaporizing carbon and one or more Group VIII transition metals with a vaporization means,

(b) transporting the vapor so formed through an annealing zone,

(c) condensing the vapor; and

(d) recovering said ropes of metallic single-wall carbon nanotubes from the material that condenses from the vapor.

16. A method in accordance with claim 15 wherein the one or more Group VIII transition metal are selected from the group of iron, cobalt, ruthenium, nickel and platinum.

17. A method in accordance with claim 15 wherein the carbon and one or more Group VIII transition metals are mixed together to form a target that is vaporized by said vaporization means to produce the vapor.

18. A method in accordance with claim 17 wherein the carbon target is maintained in an annealing zone.

19. A method in accordance with claim 15 wherein the average diameter of all single-wall carbon nanotubes in the rope is 13.8 Å

±

0.3 Å

.

20. A method in accordance with claim 15 wherein the average diameter of all single-wall carbon nanotubes in the rope is 13.8 Å

±

0.2 Å

.

21. A method in accordance with claim 15 wherein the ropes are in the form of a 2-D triangular with lattice constant of 17 Å

.

34. A method in accordance with any one of claims 2, 7, 15, or 30 wherein the annealing zone atmosphere consists essentially of carbon, and one or more transition metals selected from the group consisting of iron, cobalt, ruthenium, nickel, and platinum.

36. A method in accordance with claim 15 wherein said rope conducts electricity.

37. A method in accordance with claim 15 wherein said single-wall nanotube rope has resistivity of about 0.34 to about 1.0 micro ohms per meter at 27°

C.

22. A method of making single-wall carbon nanotubes which comprises:

(a) making a first vapor comprising carbon and one or more Group VIII transition metals by vaporizing a mixture of carbon and one or more Group VIII transition metals with a first vaporization means;

(b) condensing the vapor to form a single-wall carbon nanotube having a live end;

(c) supplying carbon vapor to the live end of the single-wall carbon nanotube while maintaining the live end of the single-wall carbon nanotube in an annealing zone, wherein ropes of single-wall carbon nanotubes are formed.

23. A method in accordance with claim 22 wherein the one or more Group VIII transition metals are selected from the group consisting of cobalt, ruthenium, nickel and platinum.

24. A method in accordance with claim 22 wherein the step of making a vapor comprising carbon and one or more Group VIII transition metals further comprises a second vaporization step timed after the making of said first vapor and before said first vapor has dissipated, resulting in the energy from the second vaporization step being absorbed by said first vapor.

25. A method of making carbon nanotubes which comprises:

(a) making a vapor comprising carbon by using a first vaporization means to perform a first vaporization to ablate material from a target comprising carbon and a Group VIII transition metal and then using a second vaporization means to perform a second vaporization, said second vaporization timed to ablate the target after the end of the first vaporization and before the material ablated by the first vaporization has dissipated and said second vaporization means focused so that the energy from the second vaporization is absorbed by the material ablated from the target by the first vaporization to form a vapor; and

(b) condensing the vapor to form carbon nanotubes, wherein at least a portion of said carbon nanotubes are single-wall carbon nanotubes in the form of ropes.

26. A method in accordance with claim 25 wherein the second vaporization arrives at the target within a delay of from about 20 nanoseconds (ns) to about 60 ns after the end of the first vaporization.

27. A method in accordance with claim 25 wherein the delay between said first vaporization and second vaporization is about 40 nanoseconds to about 50 nanoseconds.

28. A method in accordance with claim 25 wherein the target further comprises one or more Group VIII transition metals.

29. A method in accordance with claim 25 wherein the vapor is condensed to form single-wall carbon nanotubes having a live end.

30. A method in accordance with claim 29 which further comprises maintaining the live end of the single-wall carbon nanotube in an annealing zone and supplying a carbon source vapor to the live end of the single-wall carbon nanotube.

31. A method in accordance with claim 29 wherein said carbon source is selected from the group consisting of graphite particles, fullerene particles, carbon vapor, carbon monoxide, and hydrocarbons.