Claims
- 1. A method of making composite particles, comprising, providing a vapor of a first material in a carrier gas flow, providing an aerosol of support particles wherein the support particles are at a lower temperature than the vapor, and contacting the aerosol and the vapor in the carrier gas flow to form particles of the first material on the support particles.
- 2. The method of claim 1 wherein the first material is metallic, and the support particles comprises a different material.
- 3. The method of claim 2 wherein the different material is non-metallic.
- 4. The method of claim 1 wherein the vapor condenses as nanoparticles on the support particles, the nanoparticles having a major dimension of about 10 nanometers or less.
- 5. The method of claim 1 wherein the support particles include at least one of individual particles and agglomerated particles.
- 6. A method of making a supported metallic catalyst, comprising, providing a vapor of a metallic catalyst material in a carrier gas flow, providing an aerosol of support particles wherein the support particles are at a lower temperature than the vapor, and contacting the aerosol and the vapor in the carrier gas flow to form particles of the metallic catalyst material on the support particles.
- 7. The method of claim 6 wherein the vapor condenses as nanoparticles on the individual support particles, the nanoparticles having a major dimension of about 10 nanometers or less.
- 8. The method of claim 6 including evaporating the metallic catalyst material in a first chamber to form the vapor, and introducing the carrier gas flow into the first chamber to carry the vapor into a second chamber where the aerosol is introduced.
- 9. The method of claim 8 including flowing the aerosol and the vapor in the carrier gas through a second orifice into a third chamber.
- 10. The method of claim 6 wherein the vapor has a vapor pressure of 0.01 torr and above in the first chamber.
- 11. The method of claim 10 wherein the vapor pressure is 0.1 torr and above.
- 12. The method of claim 6 wherein the carrier gas flow comprises an inert gas or reducing gas.
- 13. The method of claim 6 wherein the aerosol includes support particles having an individual or agglomerated particle diameter in the range of 0.1 to 50 micrometers.
- 14. The method of claim 6 wherein the support particles comprise a metal oxide.
- 15. The method of claim 14 wherein the metal oxide is selected from the group consisting of alumina, titania, and silica.
- 16. The method of claim 6 wherein the metallic catalyst material comprises a noble metal selected from the group consisting of Au, Ag, Pd, Pt, Rh, and Ru.
- 17. The method of claim 8 including disposing the first chamber within the second chamber with the orifice extending through a wall between the first chamber and the second chamber and with the orifice communicating with a third chamber via a secondary orifice.
- 18. The method of claim 8 including disposing the first chamber with an end wall having the orifice therein communicating with the second chamber and communicating with a secondary orifice in a facing end wall of a third chamber.
- 19. A method of making a supported metallic catalyst, comprising, flowing a carrier gas through a first chamber containing a vapor of a metallic catalyst material, discharging the carrier gas and the vapor from the first chamber through an orifice as a gas jet into a second chamber, flowing an aerosol of support particles in the second chamber in a manner that the aerosol contacts the gas jet in the second chamber, and condensing the vapor in the gas jet as nanoparticles on the support particles.
- 20. Composite particles, comprising a plurality of nanoparticles condensed on one or more support particles, the nanoparticles comprising a material different from that of the support particles and having a major dimension of about 10 nanometers or less.
- 21. Supported metallic catalyst, comprising a plurality of nanoparticles condensed on one or more support particles, the nanoparticles comprising a catalytic metallic material and having a major dimension of about 10 nanometers or less.
- 22. The catalyst of claim 21 wherein individual or agglomerated support particles each has a major dimension in the range of 0.1 to 50 micrometers.
- 23. The catalyst of claim 21 wherein the nanoparticles comprise a noble metal and the support particle comprises a metal oxide.
- 24. The catalyst of claim 21 comprising noble metal nanoparticles condensed on an alumina support particle.
- 25. Apparatus for making composite particles, comprising a first chamber having means for forming a vapor of a first material in said first chamber, means for flowing a carrier gas in said first chamber, and an orifice through which the carrier gas and the vapor are discharged as a gas jet to a second chamber, and means for introducing an aerosol of support particles in the second chamber in a manner that the gas jet and the aerosol come into contact to deposit nanoparticles of the first material on individual support particles.
- 26. The apparatus of claim 25 wherein the first chamber is disposed within the second chamber and the orifice extends through a wall between the first chamber and the second chamber.
- 27. The apparatus of claim 26 further comprising a third chamber communicating with the second chamber via a secondary orifice which is laterally aligned with said orifice.
- 28. The apparatus of claim 27 wherein an aerosol inlet is disposed at a junction between the second chamber and the third chamber.
- 29. The apparatus of claim 25 wherein the first chamber includes an end wall having the orifice therein communicating with the second chamber, the second chamber communicating with a third chamber via a secondary orifice disposed in an end wall of the third chamber and axially aligned with said orifice.
- 30. The apparatus of claim 25 including a crucible for containing molten metallic material in the first chamber and from which crucible the vapor is evaporated.
- 31. The apparatus of claim 25 including a wick from which molten metallic material is evaporated.
Parent Case Info
[0001] This application claims the benefits of provisional application Serial No. 60/408,406 filed Sep. 5, 2002.
CONTRACTUAL ORIGIN OF THE INVENTION
[0002] This invention was made in part using funds obtained from the U.S. Government National Science Foundation Grant No. CHE-9810378/004, and the U.S. Government may therefore have certain rights in the invention.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60408406 |
Sep 2002 |
US |