Process for group III-V semiconductor nanostructure synthesis and compositions made using same
View Patent ↗Methods for producing nanostructures, particularly Group III-V semiconductor nanostructures, are provided. The methods include use of novel Group III and/or Group V precursors, novel surfactants, oxide acceptors, high temperature, and/or stable co-products. Related compositions are also described. Methods and compositions for producing Group III inorganic compounds that can be used as precursors for nanostructure synthesis are provided. Methods for increasing the yield of nanostructures from a synthesis reaction by removal of a vaporous by-product are also described.
1. A method for production of Group III-V semiconductor nanostructures, the method comprising:
providing one or more surfactants;
providing a first precursor comprising a Group V atom;
providing a second precursor comprising a tricarboxylate substituted Group III atom;
heating the one or more surfactants to a first temperature;
contacting the first and second precursors and the one or more heated surfactants, whereby the first and second precursors react to form nuclei capable of nucleating nanostructure growth; and,
maintaining the first and second precursors, the one or more surfactants, and the nuclei at a second temperature, the second temperature permitting growth of the nuclei to produce the nanostructures, whereby the first and second precursors react to grow the nanostructures from the nuclei.
2. The method of claim 1 , wherein the first temperature is at least 300° C.
3. The method of claim 1 , wherein the second temperature is at least 250° C.
4. The method of claim 1 , wherein the first temperature is greater than the second temperature by about 40-80° C., about 20-40° C., about 10-20° C., about 5-10° C., or about 0-5° C.
5. The method of claim 1 , wherein each of the one or more surfactants has a boiling point that is greater than the first and second temperatures.
6. The method of claim 1 , wherein the one or more surfactants comprise at least a second surfactant.
7. The method of claim 6 , wherein the second surfactant is an alkyl amine, or wherein the second surfactant is a phosphonic acid, a phosphinic acid, a carboxylic acid, a boronic acid, or a sulfonic acid, or a deprotonated form or a condensate thereof.
8. The method of claim 7 , wherein the second surfactant is a C2-30 alkylphosphonic acid, a C2-30 bialkylphosphinic acid, or a C2-30 alkylcarboxylic acid.
9. The method of claim 1 , wherein the one or more surfactants comprise a first surfactant and a second surfactant, whereby the shape of the nanostructures produced is capable of being controlled by adjusting the ratio of the first and second surfactants.
10. The method of claim 9 , wherein the ratio of the first and second surfactants is adjusted to produce substantially spherical nanocrystals.
11. The method of claim 9 , wherein the ratio of the first and second surfactants is adjusted to produce one or more of: nanorods, branched nanostructures, or nanotetrapods.
12. The method of claim 1 , wherein reacting the first and second precursors comprises reacting the first and second precursors in the presence of a second surfactant, whereby the shape of the nanostructures produced is capable of being controlled by adjusting the ratio of the second surfactant and the first or second precursor.
13. The method of claim 12 , wherein the ratio of the second surfactant and the first or second precursor is adjusted to produce substantially spherical nanocrystals.
14. The method of claim 12 , wherein the ratio of the second surfactant and the first or second precursor is adjusted to produce one or more of: nanorods, branched nanostructures, or nanotetrapods.
15. The method of claim 1 , wherein the ratio of the first and second precursors is adjusted to control the shape of the nanostructures produced.
16. The method of claim 15 , wherein the ratio of the first and second precursors is adjusted to produce substantially spherical nanocrystals.
17. The method of claim 15 , wherein the ratio of the first and second precursors is adjusted to produce one or more of: nanorods, branched nanostructures, or nanotetrapods.
18. The method of claim 1 , wherein the Group V atom is selected from the group consisting of N, P, As, Sb, and Bi.
19. The method of claim 1 , wherein the Group III atom is selected from the group consisting of: B, Al, Ga, In, and Tl.
20. The method of claim 1 , wherein the Group III-V semiconductor nanostructures comprise InN, InP, InAs, InSb, GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, or AlSb.
21. The method of claim 1 , wherein the nanostructures comprise one or more of: nanocrystals, substantially spherical nanocrystals, nanorods, branched nanostructures, or nanotetrapods.
22. A nanostructure, nanocrystal, substantially spherical nanocrystal, nanorod, branched nanostructure, or nanotetrapod produced by the method of claim 1 .
23. The method of claim 1 , wherein the one or more surfactants comprise at least a first surfactant.
24. The method of claim 23 , wherein the first surfactant is an alkyl amine, a monoalkyl amine, or a bialkyl amine.
25. The method of claim 23 , wherein the first surfactant is a tri-n-alkyl phosphine or a tri-n-alkyl phosphine oxide.
26. The method of claim 25 , wherein the first surfactant is a C12-C30 tri-n-alkyl phosphine.
27. The method of claim 26 , wherein the first surfactant is tri-n-dodecyl phosphine or tri-n-hexadecyl phosphine.
28. The method of claim 1 , wherein the first temperature is at least 360° C. and/or the second temperature is at least 300° C.
29. The method of claim 1 , wherein the second precursor comprises a tristearate substituted Group III atom.
30. The method of claim 1 , wherein the second precursor is an indium tricarboxylate.
31. The method of claim 1 , wherein the second precursor is an indium tristearate.
32. The method of claim 31 , wherein the first precursor comprises a trialkyl substituted Group V atom.
33. A composition, comprising: one or more surfactants, a first precursor comprising a Group V atom, and a second precursor comprising a tricarboxylate substituted Group III atom.