Methods for coating particles and particles produced thereby
View Patent ↗Methods of coating core materials by providing target materials and core materials; ablating the target materials to form ablated particulate target materials; and coating the core materials with said ablated particulate target materials; wherein the method is performed at a pressure of about 10 Torr or higher. Methods of coating particles with nanometer to multiple nanometer thick coatings in atmospheric pressure, and using pneumatic fluidization, are also provided.
1. A fluidized bed coating apparatus for coating core particles by ablation of a coating material, comprising:
(a) a coating chamber configured to receive core particles as a substrate intended to be coated, comprising at least one wall;
(b) a transparent window located within the wall of the coating chamber;
(c) a matrix target located within the coating chamber, comprising a coating material;
(d) a gas distributor configured to fluidize the core particles within the chamber by passing gas flow through the core particles; and
(e) a laser configured to ablate the coating material by directing energy through the transparent window toward the matrix target,
wherein the apparatus is configured to coat the core particles at a pressure higher than 10 Torr.
2. The coating apparatus according to claim 1 , wherein the laser is a pulsed laser.
3. The coating apparatus according to claim 1 , wherein the coating material is located at a position higher than the laser.
4. The coating apparatus according to claim 1 , wherein the coating material is located at a position lower than the laser.
5. The coating apparatus according to claim 1 , wherein the transparent window comprises a quartz window.
6. The coating apparatus according to claim 1 , further comprising an exhaust port.
7. The coating apparatus according to claim 1 , further comprising a mechanical agitator.
8. The coating apparatus according to claim 7 , wherein the mechanical agitator comprises a rotational agitator.
9. The coating apparatus according to claim 7 , wherein the mechanical agitator comprises a vibrational agitator.
10. The coating apparatus according to claim 1 , further comprising a temperature controller.
11. The coating apparatus according to claim 1 , wherein the coating chamber is configured to accept an inert gas selected from helium, argon, and nitrogen.
12. The coating apparatus according to claim 1 , wherein the coating chamber is configured to accept a reactive gas selected from oxygen, ammonia, and nitrous oxide.
13. The coating apparatus according to claim 1 , further comprising a filter assembly.
14. The coating apparatus according to claim 1 , wherein the coating chamber includes a feeder.
15. The coating apparatus according to claim 1 , wherein the coating chamber includes an exit port.
16. The coating apparatus according to claim 1 , wherein the coating chamber includes a feeder and an exit port.
17. The coating apparatus according to claim 16 , wherein the feeder is for introducing particles to be coated or re-coated, and the exit port is an outlet for coated particles.
18. The coating apparatus of claim 1 , wherein the coating on the fluidized core particles is substantially uniform.
19. The coating apparatus of claim 1 , wherein the coating on the fluidized core particles is substantially non-porous.
20. The coating apparatus of claim 1 , wherein the apparatus is configured to coat fluidized core particles at a pressure between 10 Torr up to or including 760 Torr.
21. The coating apparatus of claim 1 , wherein the apparatus is configured to coat fluidized core particles at about 760 Torr.