Method for low temperature synthesis of single wall carbon nanotubes

• US 7,338,648 B2
• Filed: 12/23/2002
• Issued: 03/04/2008
• Est. Priority Date: 12/28/2001
• Status: Expired due to Fees

• Current Assignee: Penn State Research Foundation
• Original Assignee: Penn State Research Foundation
• Inventors: Harutyunyan, Avetik, Pradhan, Bhabendra K., Eklund, Peter C.
• Primary Examiner(s): HENDRICKSON, STUART L
• Application Number:
  US10/326,276
• Publication Number:
  US 20040091416A1
• Time in Patent Office: 1,898 Days
• Field of Search: 423/447.3, 977/843
• US Class Current: 423/447.3
• 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 9/1272 Methane
• CPC Class Codes: Y10S 977/843 Gas phase catalytic growth, i.e. chemical vapor deposition

Abstract

The present invention is directed towards a method of producing single wall carbon nanotubes which comprises providing a catalyst comprising an alumina support and a component selected from the group consisting of reduced Fe, reduced Fe/Mo, Fe oxide, and Fe/Mo oxide, and growing, in an inert atmosphere, single wall carbon nanotubes by passing a gas comprising methane over the catalyst at a temperature and for a time sufficient to grow single wall carbon nanotubes. The invention is also directed towards a single wall carbon nanotube produced by such a method. The invention is also directed towards a catalyst for producing SWNTs, wherein the catalyst comprises an alumina support and a component selected from the group consisting of reduced Fe, reduced Fe/Mo, Fe oxide, and Fe/Mo oxide.

Claims

1. A method of producing single wall carbon nanotubes at temperatures below 800°

C., wherein said method comprises;

(a) providing a catalyst comprising an alumina support and Fe/Mo oxide; and

(b) growing in an inert atmosphere, single wall carbon nanotubes by passing a gas comprising methane over the catalyst at a temperature that is more than 600°

C. and less than 800°

C. and for a time sufficient to grow single wall carbon nanotubes.

2. The method of claim 1, wherein the ratio of Fe:

Mo;

alumina in the catalyst is about 1;

0.2;

16 by weight percent.

3. The method of claim 1, wherein the ratio of Fe:

Mo;

alumina in the catalyst is about 1-8;

0;

01-0.5;

1-24 by weight percent.

4. The method of claim 1, wherein the ratio of Fe:

Mo;

alumina in the catalyst is about 1-5;

0.01-0.5;

1-24 by weight percent when the component is Fe/Mo oxide.

5. The method of claim 1, wherein the time is in a range of 15-120 minutes.

6. The method of claim 5, wherein the time is about 90 minutes.

7. The method of claim 1, wherein the methane gas is diluted in an inert gas.

8. The method of claim 7, wherein the methane is applied at 40-100 cc/mm and the inert gas is applied at 300-400 cc/mm.

9. The method of claim 7, wherein the inert gas is argon.

10. A method of producing single wall carbon nanotubes, the method comprising applying a hydrocarbon gas to a catalyst comprising Fe/Mo oxide at a temperature in the range of 600°

C. to about 680°

C. to form the single wall carbon nanotubes.

11. A method of producing single wall carbon nanotubes at temperatures below 800°

C., wherein said method comprises;

(a) providing a catalyst comprising Fe/Mo oxide, and (b) growing in an inert atmosphere, single wall carbon nanotubes by passing a hydrocarbon gas over the catalyst at a temperature below 800°

C. and for a time sufficient to grow single wall carbon nanotubes.

12. The method of claim 11, wherein the yield of single wall carbon nanotubes is at least 16 weight percent.

13. The method of claim 11, wherein the ratio of Fe:

Mo;

alumina in the catalyst is about 1-8;

0;

01-0.5;

1-24.

14. The method of claim 11, wherein the ratio of Fe:

Mo;

alumina in the catalyst is about 1;

0.2;

16 by weight.