Light-emitting nanoparticles and methods of making same
View Patent ↗A method for the production of a robust, chemically stable, crystalline, passivated nanoparticle and composition containing the same, that emit light with high efficiencies and size-tunable and excitation energy tunable color. The methods include the thermal degradation of a precursor molecule in the presence of a capping agent at high temperature and elevated pressure. A particular composition prepared by the methods is a passivated silicon nanoparticle composition displaying discrete optical transitions.
1. A method for making nanoparticles, comprising: providing an organometallic material selected from the group consisting of silicon, germanium and tin, disposed in a fluidic medium comprising a material selected from the group consisting of alcohols, amines and thiols, and thermally decomposing the organometallic material to form nanoparticles.
2. The method of claim 1 , wherein the organometallic material is an organosilane.
3. The method of claim 2 , wherein the organosilane is diphenylsilane.
4. The method of claim 1 , wherein the organometallic material is dissolved in the fluidic medium.
5. The method of claim 1 , wherein the fluidic medium further comprises a hydrocarbon.
6. The method of claim 1 , wherein thermally decomposing the organometallic material occurs at a temperature within the range of 300° C. to 800° C.
7. The method of claim 1 , wherein thermally decomposing the organometallic material occurs at a temperature above 500° C.
8. The method of claim 1 , wherein thermally decomposing the organometallic material occurs at a pressure within the range of 140 to 345 bars.
9. The method of claim 1 , wherein the nanoparticles comprise a material selected from the group consisting of silicon and germanium.
10. The method of claim 9 , wherein the nanoparticles have an average particle diameter of 20 to about 100 Å.
11. The method of claim 9 , wherein the nanoparticles exhibit photoluminescence.
12. The method of claim 1 , further comprising:
extracting the nanoparticles with a suitable solvent; and
drying the nanoparticles.
13. The method of claim 1 , wherein the nanoparticles have a core-and-shell construction, and wherein the shell comprises an inorganic oxide.
14. The method of claim 1 , wherein the fluidic medium is a supercritical fluid.
15. The method of claim 1 , wherein the fluidic medium is a liquid medium.
16. The method of claim 1 , wherein thermally decomposing the organometallic material forms a suspension of the nanoparticles in the fluidic medium.
17. The method of claim 1 , wherein the material is an alcohol.
18. The method of claim 17 , wherein the alcohol is an n-alcohol having between 1 to 20 carbon atoms.
19. The method of claim 17 , wherein the alcohol is octanol.
20. The method of claim 1 , wherein the material is a thiol.
21. The method of claim 20 , wherein the thiol is a 1-thiol having between 1 to 20 carbon atoms.
22. The method of claim 1 , wherein the material is an amine.
23. A method for making nanoparticles, comprising:
providing an organometallic material disposed in a fluidic medium, wherein the organometallic material comprises a first composition selected from the group consisting of organosilanes and organogermanes, and wherein the fluidic medium comprises a second composition selected from the group consisting of alcohols, amines and thiols; and
thermally decomposing the organometallic material at a temperature within the range of 300° C. to 800° C. to form nanoparticles.
24. The method of claim 23 , wherein the organometallic material is an organosilane.
25. The method of claim 23 , wherein thermally decomposing the organometallic material occurs at a temperature above 500° C.
26. The method of claim 23 , wherein thermally decomposing the organometallic material occurs at a pressure within the range of 140 to 345 bars.
27. The method of claim 23 , wherein the nanoparticles have an average particle diameter of 20 to about 100 Å.
28. The method of claim 23 , wherein the nanoparticles have a core-and-shell construction.
29. The method of claim 23 , wherein the fluidic medium is a supercritical fluid.
30. The method of claim 23 , wherein the fluidic medium is a liquid medium.
31. The method of claim 23 , wherein the second composition is an n-alcohol having between 1 to 20 carbon atoms.
32. The method of claim 23 , wherein the thiol is a 1 -thiol having between 1 to 20 carbon atoms.