Gas-phase nucleation and growth of single-wall carbon nanotubes from high pressure CO

• US 6,761,870 B1
• Filed: 07/01/2002
• Issued: 07/13/2004
• Est. Priority Date: 11/03/1998
• Status: Expired due to Term

• Current Assignee: Rice University
• Original Assignee: Rice University
• Inventors: Bronikowski, Michael J., Smith, Ken A., Rohmund, Frank, Bradley, Robert K., Smalley, Richard E., Nikolaev, Pavel, Colbert, Daniel T.
• Primary Examiner(s): Hendrickson, Stuart L.
• Assistant Examiner(s): Lish, Peter J
• Application Number:
  US09/830,642
• Time in Patent Office: 743 Days
• Field of Search: 423/447.3, 423/447.1, 423/445.B, 423/455.R
• 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: B01J 4/002 Nozzle-type elements nozzle-type reactors B01J19/26
• 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 2202/36 Diameter
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: D01F 9/1278 Carbon monoxide
• CPC Class Codes: Y10S 977/75 Single-walled
• CPC Class Codes: Y10S 977/751 with specified chirality and/or electrical conductivity
• CPC Class Codes: Y10S 977/843 Gas phase catalytic growth, i.e. chemical vapor deposition
• CPC Class Codes: Y10S 977/845 Purification or separation of fullerenes or nanotubes
• CPC Class Codes: Y10S 977/951 Laser
• CPC Class Codes: Y10T 428/30 Self-sustaining carbon mass or layer with impregnant or other layer

Abstract

The present invention discloses the process of supplying high pressure (e.g., 30 atmospheres) CO that has been preheated (e.g., to about 1000° C.) and a catalyst precursor gas (e.g., Fe(CO)₅) in CO that is kept below the catalyst precursor decomposition temperature to a mixing zone. In this mixing zone, the catalyst precursor is rapidly heated to a temperature that results in (1) precursor decomposition, (2) formation of active catalyst metal atom clusters of the appropriate size, and (3) favorable growth of SWNTs on the catalyst clusters. Preferably a catalyst cluster nucleation agency is employed to enable rapid reaction of the catalyst precursor gas to form many small, active catalyst particles instead of a few large, inactive ones. Such nucleation agencies can include auxiliary metal precursors that cluster more rapidly than the primary catalyst, or through provision of additional energy inputs (e.g., from a pulsed or CW laser) directed precisely at the region where cluster formation is desired. Under these conditions SWNTs nucleate and grow according to the Boudouard reaction. The SWNTs thus formed may be recovered directly or passed through a growth and annealing zone maintained at an elevated temperature (e.g., 1000° C.) in which tubes may continue to grow and coalesce into ropes.

Claims

1. A method for producing single wall carbon nanotubes comprising the steps of:

(a) providing a CO gas stream comprising CO, wherein said CO gas stream is at a pressure greater than about 10 atmospheres;

(b) providing a gaseous catalyst precursor stream comprising a catalyst precursor;

(c) mixing the CO gas stream and the gaseous catalyst precursor stream to form a reaction mixture, wherein said mixing step occurs under reaction conditions to form single wall carbon nanotubes; and

(d) reacting said reaction mixture to form single wall carbon nanotubes.

2. The method of claim 1, wherein the pressure of the CO gas stream is in a range from about 10 atmospheres to about 100 atmospheres.

3. The method of claim 1, wherein the gaseous catalyst precursor stream comprises atoms of a transition metal selected from the group consisting of Group VI metals, Group VII metals, and mixtures thereof.

4. The method of claim 1, wherein said catalyst precursor is a metal-containing compound of a metal selected from the group consisting of tungsten, molybdenum, chromium, iron, nickel, cobalt, rhodium, ruthenium, palladium, osmium, iridium, platinum and mixtures thereof.

5. The method of claim 4, wherein said metal-containing compound is a metal carbonyl.

6. The method of claim 5, wherein said metal carbonyl is selected from the group consisting of Fe(CO)₅, Co(CO)₆, and mixtures thereof.

7. The method of claim 4, wherein said metal-containing compound is a metallocene.

8. The method of claim 7, wherein the metallocene is selected from the group consisting of ferrocene, cobaltocene, ruthenocene and mixtures thereof.

9. The method of claim 1, wherein said gaseous catalyst precursor stream comprises CO.

10. The method of claim 9, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is from about 0.25 Torr to about 100 Torr.

11. The method of claim 9, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is up to about 100 Torr.

12. The method of claim 9, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is at least about 0.01 Torr.

13. The method of claim 9, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is from about 1 Torr to about 10 Torr.

14. The method of claim 1, wherein the concentration of catalyst precursor in the reaction mixture is in the range from about 1 ppm to about 100 ppm.

15. The method of claim 1, wherein the concentration of catalyst precursor in the reaction mixture is in the range from about 10 ppm to about 30 ppm.

16. The method of claim 1, wherein said gaseous catalyst precursor stream is provided at a temperature in the range of from about 70°

C. to about 200°

C.

17. The method of claim 1, wherein said CO gas stream is provided at a temperature in the range of from about 850°

C. to about 1500°

C.

18. The method of claim 1, wherein said CO gas stream is provided at a temperature in the range of from about 900°

C. to about 1100°

C.

19. The method of claim 1, wherein said mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in less than about 100 μ

sec.

20. The method of claim 1, wherein said mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in up to about 10 msec.

21. The method of claim 1, wherein said mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in between about 1 μ

sec and about 1 msec.

22. The method of claim 1, wherein the reaction conditions of said mixing step comprises a reaction temperature greater than the decomposition temperature of the catalyst precursor.

23. The method of claim 1, wherein the reaction conditions of said mixing step comprises a reaction temperature in the range of from about 850°

C. to about 1250°

C.

24. The method of claim 1, wherein a catalyst promoter is added to the reaction mixture.

25. The method of claim 24, wherein the catalyst promoter is selected from the group consisting of thiophene, H₂S, volatile lead, bismuth compounds and combinations thereof.

26. The method of claim 1, wherein the CO gas stream further comprises CO₂.

27. The method of claim 1, wherein a plurality of the single wall carbon nanotubes have a tube diameter in the range of from about 0.6 nm to about 2 nm.

28. The method of claim 1, wherein a plurality of the single wall carbon nanotubes have a tube diameter in the range of from about 0.6 nm to about 0.8 nm.

29. The method of claim 1, wherein at least 50% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

30. The method of claim 1, wherein at least 75% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

31. The method of claim 1, wherein at least 95% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

32. The method of claim 1, wherein a plurality of said single wall carbon nanotubes have diameters in the range from about the diameter of a (5,5) nanotube to about the diameter of a (10,10) nanotube.

33. The method of claim 1, wherein said formed single wall carbon nanotubes are at least 25% (5,5) nanotubes.

34. The method of claim 1, wherein said formed single wall carbon nanotubes are at least 50% (5,5) nanotubes.

35. The method of claim 1, wherein at least some of the single wall carbon nanotubes are in the form of ropes.

36. A method for producing single wall carbon nanotubes comprising the steps of:

(a) providing a CO gas stream comprising CO, wherein said CO is at a superatmospheric pressure;

(b) providing a gaseous catalyst precursor stream comprising a catalyst precursor, wherein

(i) said catalyst precursor comprises atoms of a transition metal selected from the group consisting of Group VI metals, Group VIII metals and mixtures thereof, and

(ii) said gaseous catalyst precursor stream is provided at a temperature below the decomposition temperature of said catalyst precursor;

(c) heating said CO gas stream comprising CO to a temperature

(i) that is at least above the decomposition temperature of said catalyst precursor and

(ii) that is sufficient to form single wall carbon nanotubes;

(d) mixing said CO gas stream and said gaseous catalyst precursor stream to form a reaction mixture, wherein said mixing step occurs in a mixing zone and wherein said mixing step rapidly heats said catalyst precursor to a temperature that is

(i) above the decomposition temperature of said catalyst precursor,

(ii) sufficient to promote the formation of catalyst metal atom clusters, and

(iii) sufficient to promote the initiation and growth of single wall carbon nanotubes; and

(c) forming solid products comprising the single wall nanotubes that are in a resulting gaseous stream, wherein at least 75% of atoms of the solid products are atoms of the single wall carbon nanotubes.

37. The method of claim 36, further comprising the step of passing said single wall carbon nanotubes in said resulting gaseous stream through a growth and annealing zone.

38. The method of claim 37, wherein the temperature of the growth and annealing zone is in the range from about 850°

C. to about 1250°

C.

39. The method of claim 37, wherein the pressure of the growth and annealing zone is in the range from about 3 to about 1000 atm.

40. The method of claim 37, wherein the pressure of the growth and annealing zone is in the range from about 5 to about 500 atm.

41. The method of claim 37, wherein the pressure of the growth and annealing zone is in the range from about 10 to about 100 atm.

42. The method of claim 36, further comprising the step of separating and recovering said single wall carbon nanotubes from said resulting gaseous stream.

43. The method of claim 42, wherein the separating and recovering step comprises passing the resulting gaseous stream through a gas permeable filter.

44. The method of claim 37 further comprising the step of separating and recovering said single wall carbon nanotubes from said resulting gaseous stream after passing the single wall carbon nanotubes and resulting gaseous stream through said growth and annealing zone.

45. The method of claim 36 further comprising the step of supplying a nucleating agent to said mixing zone to facilitate the formation of said catalyst metal atom clusters.

46. The method of claim 45, wherein said nucleating agent is a gaseous metal-containing compound.

47. The method of claim 46, wherein said gaseous metal-containing compound is selected from the group consisting of Ni(CO)₄, W(CO)₆, Mo(CO)₆, and mixtures thereof.

48. The method of claim 45, wherein said nucleating agent is laser light photons.

49. The method of claim 36, wherein the CO gas stream is at a pressure range from about 3 atmospheres to about 1000 atmospheres.

50. The method of claim 36, wherein the CO gas stream is at a pressure range from about 10 atmospheres to about 100 atmospheres.

51. The method of claim 36, wherein said catalyst precursor is a metal-containing compound of a metal selected from the group consisting of tungsten, molybdenum, chromium, iron, nickel, cobalt, rhodium, ruthenium, palladium, osmium, iridium, platinum and mixtures thereof.

52. The method of claim 51, wherein said metal-containing compound is a metal carbonyl.

53. The method of claim 52, wherein said metal carbonyl is selected from the group consisting of Fe(CO)₅, Co(CO)₆, and mixtures thereof.

54. The method of claim 51, wherein said metal-containing compound is a metallocene.

55. The method of claim 54, wherein the metallocene is selected from the group consisting of ferrocene, cobaltocene, ruthenocene and mixtures thereof.

56. The method of claim 36, wherein said gaseous catalyst precursor stream comprises CO.

57. The method of claim 56, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is from about 0.25 Torr to about 100 Torr.

58. The method of claim 56, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is up to about 100 Torr.

59. The method of claim 56, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is at least about 0.10 Torr.

60. The method of claim 56, wherein the partial pressure of said catalyst precursor in said gaseous catalyst precursor stream is from about 1 Torr to about 10 Torr.

61. The method of claim 36, wherein the concentration of catalyst precursor in the reaction mixture is in the range from about 1 ppm to about 100 ppm.

62. The method of claim 36, wherein the concentration of catalyst precursor in the reaction mixture is in the range from about 10 ppm to about 30 ppm.

63. The method of claim 36, wherein said gaseous catalyst precursor stream is supplied at a temperature in the range of from about 70°

C. to about 200°

C.

64. The method of claim 36, wherein said CO gas stream is supplied at a temperature in the range of from about 850°

C. to about 1500°

C.

65. The method of claim 36, wherein said CO gas stream is supplied at a temperature in the range of from about 900°

C. to about 1100°

C.

66. The method of claim 36, wherein said mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in less than about 100 μ

sec.

67. The method of claim 36, wherein said mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in up to about 10 msec.

68. The method of claim 36, wherein the mixing step heats said catalyst precursor to a temperature above the decomposition temperature of said catalyst precursor in between about 1 μ

sec and about 1 msec.

69. The method of claim 36, wherein the reaction conditions of said mixing step comprise a reaction temperature in the range of from about 850°

C. to about 1250°

C.

70. The method of claim 36, wherein a catalyst promoter is added to the reaction mixture.

71. The method of claim 70, wherein the catalyst promoter is selected from the group consisting of thiophene, H₂S, volatile lead, bismuth compounds and combinations thereof.

72. The method of claim 36 further comprising the step of controlling the diameter of the single wall carbon nanotubes by controlling the catalyst cluster size at the time the growth reaction is initiated.

73. The method of claim 72, wherein said catalyst cluster size is controlled by a method selected from the group consisting of:

(a) controlling the partial pressure of CO (P_CO) in the mixing zone;

(b) controlling the temperature in the mixing zone;

(c) controlling the partial pressure of the catalyst precursor (P_CAT) provided to the mixing zone;

(d) controlling the partial pressure of nucleating agents (P_N) provided to the mixing zone; and

(e) combinations of the foregoing.

74. The method of claim 72, wherein said catalyst cluster size is controlled by controlling the ratio of the partial pressure of CO (P_CO) in the mixing zone to the partial pressure of the catalyst precursor (P_CAT).

75. The method of claim 36, further comprising the step of changing the reaction conditions from a first set of reaction conditions to a second set of reaction conditions, wherein,

(a) the first set of reaction conditions promote the formation of said catalyst metal clusters during the mixing of said CO gas stream and said catalyst precursor gaseous stream;

and

(b) the second set of reaction conditions promote the formation of single wall carbon nanotubes.

76. The method of claim 36, wherein the CO gas stream further comprises CO₂.

77. The method of claim 36, wherein said catalyst precursor is contacted with a laser beam.

78. The method of claim 36, wherein said catalyst precursor is contacted with a laser beam upon entering the mixing zone to dissociate said catalyst precursor.

79. The method of claim 78 further comprising the step of adding CO₂ downstream of where the laser beam contacts the catalyst precursor.

80. The method of claim 78 further comprising a step selected from the group consisting of adding CO₂ to the CO gas stream, adding CO₂ downstream of the where the laser beam contacts the catalyst precursor, and adding CO₂ at both locations.

81. The method of claim 36, wherein at least 99% of atoms of the solid products are atoms of the single wall carbon nanotubes.

82. The method of claim 36, wherein a plurality of the single wall carbon nanotubes have a tube diameter in the range of from about 0.6 nm to about 2 nm.

83. The method of claim 36, wherein a plurality of the single wall carbon nanotubes have a tube diameter in the range of from about 0.6 nm to about 0.8 nm.

84. The method of claim 36, wherein at least 50% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

85. The method of claim 36, wherein at least 75% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

86. The method of claim 36, wherein at least 95% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

87. The method of claim 36, wherein a plurality of said single wall carbon nanotubes have diameters in the range from about the diameter of a (5,5) nanotube to about the diameter of a (10,10) nanotube.

88. The method of claim 36, wherein said single wall carbon nanotubes are at least 25% (5,5) nanotubes.

89. The method of claim 36, wherein said single wall carbon nanotubes are at least 50% (5,5) nanotubes.

90. The method of claim 36, wherein the solid products comprise ropes of the single wall carbon nanotubes.

91. A method for producing single wall carbon nanotubes comprising the steps of:

(a) providing a CO gas stream comprising CO, wherein said CO is at a pressure of about at least 3 atmospheres;

(b) providing a gaseous catalyst precursor stream comprising a catalyst precursor, wherein

(i) said catalyst precursor comprises atoms of a transition metal selected from the group consisting of Group VI metals, Group VIII metals and mixtures thereof, and

(ii) said gaseous catalyst precursor stream being provided at a temperature below the decomposition temperature of said catalyst precursor;

(c) heating said CO gas stream to a temperature

(i) that is at least above the decomposition temperature of said catalyst precursor and

(ii) that is sufficient to form single wall carbon nanotubes;

(d) mixing said CO gas stream with said gaseous catalyst precursor stream to form a reaction mixture, wherein said mixing step occurs in a mixing zone and wherein said mixing step rapidly heats said catalyst precursor to a temperature that is

(i) above the decomposition temperature of said catalyst precursor,

(ii) sufficient to promote the formation of catalyst metal atom clusters and

(iii) sufficient to promote the initiation and growth of single wall carbon nanotubes;

(e) supplying a nucleating agent to said mixing zone to facilitate the formation of said catalyst metal atom clusters; and

(f) forming solid products, wherein greater than about 75% of atoms of the solid products are atoms of the single wall carbon nanotubes.

92. The method of claim 91, wherein the catalyst precursor is selected from the group consisting of metallocenes, metal carbonyls, and mixtures thereof.

93. The method for producing single wall carbon nanotubes comprising the steps of:

(a) providing a CO gas stream comprising CO, wherein said CO gas stream is at a superatmospheric pressure;

(b) providing a gaseous catalyst precursor stream comprising a catalyst precursor;

(c) mixing the CO gas stream and the gaseous catalyst precursor stream to form a reaction mixture, wherein said mixing step occurs under reaction conditions to form single wall carbon nanotubes; and

(d) reacting said reaction mixture to form carbon products in tubular form, wherein at least 75 atom % of the carbon products in tubular form are single wall carbon nanotubes.

94. The method of claim 93, wherein at least 99 atom % of the solid carbon products in tubular form are single wall carbon nanotubes.

95. The method of claim 93, further comprising the step of passing said single wall carbon nanotubes through a growth and annealing zone.

96. The method of claim 95, wherein the temperature of the growth and annealing zone is in the range from about 850°

C. to about 1250°

C.

97. The method of claim 95, wherein the pressure of the growth and annealing zone is in the range from about 3 to about 1000 atm.

98. The method of claim 95, wherein the pressure of the growth and annealing zone is in the range from about 5 to about 500 atm.

99. The method of claim 95, wherein the pressure of the growth and annealing zone is in the range from about 10 to about 100 atm.

100. The method of claim 93, wherein the reacting step forms the carbon products in a resulting gaseous stream, and said method further comprises the step of separating and recovering said single wall carbon nanotubes from the resulting gaseous stream.

101. The method of claim 93, wherein said mixing step occurs in a mixing zone and said method further comprises the step of supplying a nucleating agent to said mixing zone to facilitate the formation of catalyst metal atom clusters.

102. The method of claim 93, wherein said catalyst precursor is a metal-containing compound comprising a metal selected from the group consisting of tungsten, molybdenum, chromium, iron, nickel, cobalt, rhodium, ruthenium, palladium, osmium, iridium, platinum and mixtures thereof.

103. The method of claim 102, wherein said metal-containing compound is a metal carbonyl.

104. The method of claim 103, wherein said metal carbonyl is selected from the group consisting of Fe(CO)₅, Co(CO)₆, and mixtures thereof.

105. The method of claim 102, wherein said metal-containing compound is a metallocene.

106. The method of claim 105, wherein the metallocene is selected from the group consisting of ferrocene, cobaltocene, ruthenocene and mixtures thereof.

107. The method of claim 93, wherein said gaseous catalyst precursor stream comprises CO.

108. The method of claim 93, wherein at least 50% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

109. The method of claim 93, wherein at least 75% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

110. The method of claim 93, wherein at least 95% of said single wall carbon nanotubes have a diameter in the range of 0.6 nm to 0.8 nm.

111. The method of claim 93, wherein a plurality of said single wall carbon nanotubes have diameters in the range from about the diameter of a (5,5) nanotube to about the diameter of a (10,10) nanotubes.

112. The method of claim 93, wherein said single wall carbon nanotubes are at least 25% (5,5) nanotubes.

113. The method of claim 93, wherein said single wall carbon nanotubes are at least 50% (5,5) nanotubes.

114. The method of claim 93, wherein the carbon products comprise ropes of single wall carbon nanotubes.

115. A method for producing single wall carbon nanotubes comprising the steps of:

(a) providing a CO gas stream comprising CO, wherein said CO gas stream is at a superatmospheric pressure;

(b) providing a gaseous catalyst precursor stream comprising a catalyst precursor;

(c) mixing the CO gas stream and the gaseous catalyst precursor stream to form a reaction mixture, wherein said mixing step occurs under reaction conditions to form single wall carbon nanotubes; and

(d) reacting said reaction mixture stream to form carbon products in tubular form, wherein at least 99 atom % of the carbon products in tubular form are single wall carbon nanotubes.