Free-standing and aligned carbon nanotubes and synthesis thereof

• US 6,863,942 B2
• Filed: 06/18/1999
• Issued: 03/08/2005
• Est. Priority Date: 06/19/1998
• Status: Expired due to Fees

• Current Assignee: The Research Foundation for The State University of New York (State University of New York)
• Original Assignee: The Research Foundation for The State University of New York (State University of New York)
• Inventors: Ren, Zhifeng, Huang, Zhongping, Wang, Dezhi, Wang, Jui H.
• Primary Examiner(s): Miggins, Michael C.
• Application Number:
  US09/336,126
• Publication Number:
  US 20030203139A1
• Time in Patent Office: 2,090 Days
• Field of Search: 428/36.9, 428/36.91, 428/36.92, 428/34.1, 423/445.R, 423/445.B, 423/447.2, 423/448, 423/449.1, 423/DIG.39, 423/DIG.40, 313/495, 313/309, 313/351, 313/497, 313/311, 313/553, 313/558, 313/496, 345/75.2, 315/169.1, 315/169.3
• US Class Current: 428/36.9
• CPC Class Codes: B82Y 10/00 Nanotechnology for information processing, storage or transmission, e.g. quantum computing or single electron logic
• 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 2202/06 Multi-walled nanotubes
• CPC Class Codes: C01B 2202/08 Aligned nanotubes
• CPC Class Codes: C01B 2202/34 Length
• CPC Class Codes: C01B 2202/36 Diameter
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: C23C 16/26 Deposition of carbon only
• CPC Class Codes: C30B 25/105 by irradiation or electric discharge
• CPC Class Codes: C30B 29/02 Elements
• CPC Class Codes: C30B 29/605 Products containing multiple oriented crystallites, e.g. columnar crystallites
• CPC Class Codes: D01F 9/12 Carbon filaments; Apparatus specially adapted for the manufacture thereof
• 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: H01J 1/304 Field-emissive cathodes
• CPC Class Codes: H01J 2201/30469 Carbon nanotubes (CNTs)
• CPC Class Codes: H01J 2329/00 Electron emission display panels, e.g. field emission display panels
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 4/04 Processes of manufacture in general
• CPC Class Codes: H01M 4/0404 by coating on electrode collectors
• CPC Class Codes: H01M 4/0421 : involving vapour deposition
• CPC Class Codes: H01M 4/0426 : Sputtering
• CPC Class Codes: H01M 4/0428 : Chemical vapour deposition
• CPC Class Codes: H01M 4/045 : Electrochemical coating; Electrochemical impregnation
• CPC Class Codes: H01M 4/0492 : Chemical attack of the support material
• CPC Class Codes: H01M 4/13 : Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
• CPC Class Codes: H01M 4/587 : for inserting or intercalating light metals
• CPC Class Codes: H01M 4/96 : Carbon-based electrodes
• CPC Class Codes: H01M 8/04089 : of gaseous reactants
• CPC Class Codes: H01M 8/04216 : characterised by the choice for a specific material, e.g. carbon, hydride, absorbent
• CPC Class Codes: H10N 60/0828 : Introducing flux pinning centres
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells
• CPC Class Codes: Y10S 423/39 : Fullerene, e.g. c60, c70 derivative and related process
• CPC Class Codes: Y10S 423/40 : Fullerene composition
• CPC Class Codes: Y10S 977/752 : Multi-walled
• CPC Class Codes: Y10S 977/843 : Gas phase catalytic growth, i.e. chemical vapor deposition
• 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: Y10S 977/952 : Display
• CPC Class Codes: Y10T 428/1307 : Bag or tubular film [e.g., pouch, flexible food casing, envelope, etc.]
• CPC Class Codes: Y10T 428/139 : Open-ended, self-supporting conduit, cylinder, or tube-type article

Abstract

One or more highly-oriented, multi-walled carbon nanotubes are grown on an outer surface of a substrate initially disposed with a catalyst film or catalyst nano-dot by plasma enhanced hot filament chemical vapor deposition of a carbon source gas and a catalyst gas at temperatures between 300° C. and 3000° C. The carbon nanotubes range from 4 to 500 nm in diameter and 0.1 to 50 μm in length depending on growth conditions. Carbon nanotube density can exceed 10⁴ nanotubes/mm². Acetylene is used as the carbon source gas, and ammonia is used as the catalyst gas. Plasma intensity, carbon source gas to catalyst gas ratio and their flow rates, catalyst film thickness, and temperature of chemical vapor deposition affect the lengths, diameters, density, and uniformity of the carbon nanotubes. The carbon nanotubes of the present invention are useful in electrochemical applications as well as in electron emission, structural composite, material storage, and microelectrode applications.

Claims

1. A product comprising:

a substrate having an outer surface and a strain point or a melting point temperature between about 300°

C. and 700°

C. and

one or more plasma enhanced chemical vapor deposited graphitized carbon nanotubes formed on and extending outwardly from the outer surface of the substrate.

2. The product according to claim 1 wherein the one or more carbon nanotubes are present at a density greater than 10⁴ nanotubes per square millimeter of substrate.

3. The product according to claim 1, wherein the one or more carbon nanotubes extend outwardly from and substantially perpendicular to the substrate.

4. The product according to claim 1, wherein the one or more carbon nanotubes extend outwardly from and at a non-perpendicular angle with respect to the substrate.

5. The product according to claim 1, wherein the one or more carbon nanotubes are substantially parallel to the substrate.

6. The product according to claim 1, wherein the one or more carbon nanotubes have a diameter between 4 to 500 nanometers.

7. The product according to claim 1, wherein the one or more carbon nanotubes have a diameter of at least 50 nanometers.

8. The product according to claim 1, wherein the substrate comprises glass, silica, quartz, silicon, iron, cobalt, nickel, an alloy of iron, cobalt, or nickel, platinum, a ceramic, or a combination thereof.

9. The product according to claim 1, wherein the substrate is a glass plate.

10. The product according to claim 1, wherein substantially all of the one or more carbon nanotubes have an open end.

11. The product according to claim 1, wherein the one or more carbon nanotubes are present at a density no greater than 10² nanotubes per square millimeter of substrate.

12. The product according to claim 1, wherein the one or more carbon nanotubes are graphitized carbon nanotubes.

13. The product according to claim 1, wherein the substrate comprises a catalyst.

14. The product according to claim 13, wherein the substrate is formed of the catalyst.

15. The product according to claim 13, wherein the catalyst is a metal or metal alloy and wherein substantially all carbon nanotubes have a cap distal from the substrate, the cap comprising the metal or metal alloy.

16. The product according to claim 15, wherein the metal or metal alloy is iron, cobalt, nickel, or an alloy of iron, cobalt, or nickel.

17. The product according to claim 16, wherein the metal or metal alloy is nickel.

18. The product according to claim 1, further comprising a filling within the one or more carbon nanotubes.

19. The product according to claim 18, wherein the filling is hydrogen, lithium ions, bismuth, lead telluride, or bismuth tritelluride.

20. The product according to claim 18, wherein the filling is a pharmacological agent.

21. The product according to claim 18, wherein the filling is enclosed within the carbon nanotubes.

22. The product according to claim 18, wherein substantially all of the one or more carbon nanotubes have an open end.

24. The product according to claim 13, wherein the substrate includes a substrate layer and a continuous or non-continuous catalyst layer between the substrate layer and the plurality of substantially aligned carbon nanotubes.

23. A field emission display comprising:

a baseplate having an electron emitting array positioned thereon, the baseplate comprising a substrate and one or more free-standing plasma-enhanced chemical vapor deposited graphitized carbon nanotubes originating and extending outwardly from an outer surface of the substrate; and

a phosphor coated plate spaced apart from the baseplate so that electrons emitted from the array impinge on the phosphor coating wherein the substrate has a strain or a melting point temperature between about 300 and 700°

C.