Method of encapsulating a material in a carbon nanotube

• US 5,916,642 A
• Filed: 11/21/1996
• Issued: 06/29/1999
• Est. Priority Date: 11/22/1995
• Status: Expired due to Fees

• Current Assignee: Northwestern University
• Original Assignee: Northwestern University
• Inventors: Chang, Robert P. H.
• Primary Examiner(s): Lewis, Michael
• Assistant Examiner(s): DI MAURO, PETER T
• Application Number:
  US08/754,545
• Time in Patent Office: 950 Days
• Field of Search: 423/445 B, 423/DIG. 39, 423/DIG. 40, 423/447.3, 204/157.47, 427/562, 427/580, 427/590, 427/249, 164/46
• US Class Current: 29/509
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C23C 14/0605 Carbon
• CPC Class Codes: C23C 14/14 Metallic material, boron or silicon
• CPC Class Codes: C23C 14/325 Electric arc evaporation
• CPC Class Codes: D01F 9/12 Carbon filaments; Apparatus specially adapted for the manufacture thereof
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/788 Of specified organic or carbon-based composition
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes
• CPC Class Codes: Y10T 29/49915 Overedge assembling of seated part
• CPC Class Codes: Y10T 29/49936 Surface interlocking
• CPC Class Codes: Y10T 29/53791 Edge binding

Abstract

A method of encapsulating a material in a carbon nanotube comprising generating a vapor of the material to be encapsulated, generating a hydrogen arc discharge that discharges encapsulating products, and contacting the vapor of the material and the products discharged from the hydrogen arc discharge proximate a surface to encapsulate the material in a carbon nanotube. A carbon nanotube encapsulating a metallic material (e.g. copper), a semi-conductor material (e.g. germanium) and other materials can be produced.

Claims

1. A method of encapsulating a material in a nanotube comprising vaporizing the material to be encapsulated, vaporizing a material comprising carbon in the presence of at least 50 Torr of molecular hydrogen to provide encapsulating material having hydrogen terminated carbon bonds, and contacting the vaporized material and said encapsulating material so that said encapsulating material forms a nanotube in-situ about said material.

2. The method of claim 1 wherein said molecular hydrogen is at a pressure below about 760 Torr.

3. The method of claim 1 wherein said vaporized material to be encapsulated and said vaporized material comprising carbon are vaporized in said molecular hydrogen by an electrical discharge between a cathode and anode.

4. The method of claim 3 wherein said anode comprises a first region comprising graphite and a second region comprising said material to be encapsulated.

5. The method of claim 4 wherein said anode second region includes an insert of said material to be encapsulated.

6. The method of claim 1 including the further step of removing the nanotube, leaving a nanowire comprising said material.

13. A method of claim 1 wherein said nanotube includes open ends.

7. A method of forming a nanotube, comprising vaporizing a first material, vaporizing a material comprising carbon in the presence of at least 50 Torr of molecular hydrogen to provide encapsulating material having hydrogen terminated carbon bonds, and contacting the vaporized material and said encapsulating material so that said encapsulating material forms a nanotube in-situ about said material.

8. The method of claim 7 wherein said molecular hydrogen is at a pressure below about 760 Torr.

9. The method of claim 7 wherein said vaporized first material and said vaporized material comprising carbon are vaporized in said molecular hydrogen by an electrical discharge between a cathode and an anode.

10. The method of claim 9 wherein said anode comprises a first region comprising graphite and a second region comprising said material to be encapsulated.

11. The method of claim 10 wherein said anode includes an insert of said material to be encapsulated.

12. The method of claim 7 including the further step of removing the nanotube, leaving a nanowire comprising said material.

14. A method of making a nanowire, comprising vaporizing a material to be encapsulated, vaporizing a second material for encapsulating said material, contacting the vaporized material and the vaporized second material to form a nanotube in-situ about said material, and removing the nanotube, leaving a nanowire comprising said material.

15. A method of making a nanowire, comprising vaporizing a first material to be encapsulated, vaporizing a second material for encapsulating said first material, contacting the vaporized first material and the vaporized second material to form a nanotube in-situ about said first material, and removing the nanotube, leaving a nanowire comprising said first material.

16. A method of encapsulating a material in a nanotube comprising vaporizing a material to be encapsulated selected from the group consisting of metals and semiconductor materials, providing encapsulating material having hydrogen terminated carbon bonds by vaporizing a material comprising a source of polycyclic aromatic hydrocarbons, and contacting the vaporized material to be encapsulated and said encapsulating material so that said encapsulating material forms a nanotube in-situ about said vaporized material to be encapsulated.