Method for producing a catalyst support and compositions thereof
This invention relates generally to a method for producing fullerene nanotube catalyst supports and compositions thereof. In one embodiment, fullerene nanotubes or fullerene nanotube structures can be employed as the support material. A transition metal catalyst is added to the fullerene nanotubes. In a preferred embodiment, the catalyst metal cluster is deposited on the open nanotube end by a docking process that insures optimum location for the subsequent growth reaction. The metal atoms may be subjected to reductive conditions.
1. A method for producing a catalyst support comprising:
(a) providing a plurality of fullerene nanotubes;
(b) contacting an end of at least some of the fullerene nanotubes of the plurality with at least one catalytic metal; and
(c) activating the catalytic metal.
2. The method of claim 1 wherein the catalyst metal is selected from the group consisting of transition metals, Group VIII metals, metals of the lanthanide series, metals of the actinide series, Iron (Fe), Nickel (Ni), Cobalt (Co), ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), platinum (Pt) and mixtures thereof.
3. The method of claim 1 further comprising removing an end cap from the end of at least some of the fullerene nanotubes.
4. The method of claim 3 wherein the end caps are removed by an oxidative treatment.
5. The method of claim 4 wherein the oxidative treatment comprises a technique selected from the group consisting of oxidative etching, electrochemical oxidative etching and combinations thereof.
6. The method of claim 4 wherein the oxidative treatment comprises the use of a chemical selected from the group consisting of nitric acid, oxygen, carbon dioxide and combinations thereof.
7. The method of claim 4 wherein the oxidative treatment is conducted at a temperature at most about 500° C.
8. The method of claim 1 further comprising cutting the fullerene nanotubes.
9. The method of claim 1 wherein the catalytic metal is deposited on the fullerene nanotubes.
10. The method of claim 9 wherein the catalytic metal is deposited by a deposition method selected from the group consisting of deposition of a metal vapor in a vacuum, deposition of pre-formed catalyst particles, deposition of a catalyst precursor and combinations thereof.
11. The method of claim 10 wherein the deposition of the metal vapor is done by heating at least one wire comprising the catalytic metal.
12. The method of claim 10 wherein the catalyst precursor is a substance selected from the group consisting of an oxide, salt, metal complex and combinations thereof.
13. The method of claim 1 wherein the activating of the catalytic metal is by heating.
14. The method of claim 13 wherein the heating is localized at the ends of the fullerene nanotubes of the plurality.
15. The method of claim 13 wherein the heating is at a temperature in a range between about 500° C. and about 1300° C.
16. The method of claim 1 wherein the activating of the catalytic metal produces metal atom clusters comprising from about 10 to about 200 metal atoms.
17. The method of claim 16 wherein the metal atom clusters are located at the ends of the fullerene nanotubes.
18. The method of claim 1 wherein the plurality of fullerene nanotubes is a cross section of a previously-grown fiber.