Processes for synthesizing nanocrystals

Patent metadata

Field	Value
Publication number	US-9284484-B2
Application number	US-201414296658-A
Country	US
Kind code	B2
Filing date	Jun 5, 2014
Priority date	Jun 7, 2013
Publication date	Mar 15, 2016
Grant date	Mar 15, 2016

Abstract

A process of synthesizing nanocrystals, the process including: obtaining a metal precursor, a non-metal precursor, a ligand compound, and an ionic liquid; and contacting the metal precursor, the non-metal precursor, the ligand compound, and the ionic liquid to form a mixture and synthesize a first semiconductor nanocrystal.

First claim

What is claimed is:

1. A process of synthesizing nanocrystals, the process comprising:
preparing a mixture comprising a metal precursor, a non-metal precursor, a ligand compound, and an ionic liquid, in an organic solvent; and
heating the mixture to trigger a reaction between the metal precursor and the non-metal precursor, thereby forming a first semiconductor nanocrystal, and
wherein the mixture further comprises a second nanocrystal, and the heating the mixture to trigger the reaction between the metal precursor and the non-metal precursor comprises forming a shell of the first semiconductor nanocrystal on a surface of the second nanocrystal to obtain a core-shell nanocrystal.

2. The process of claim 1 , wherein the organic solvent is a hydrophobic solvent.

3. The process of claim 2 , wherein the hydrophobic solvent is selected from a C6 to C22 primary alkyl amine, a C6 to C22 secondary alkyl amine, C6 to C40 tertiary alkyl amine, a heterocyclic compound having a nitrogen atom, a C6 to C40 aliphatic hydrocarbon, an aromatic hydrocarbon substituted with a C6 to C30 alkyl group, a phosphine substituted with a C6 to C22 alkyl group, a phosphine oxide substituted with a C6 to C22 alkyl group, a C12 to C22 aromatic ether, and a combination thereof.

4. The process of claim 1 , wherein the metal precursor comprises a metal selected from a Group II metal, a Group III metal, a Group IV metal, and a combination thereof, and wherein the metal precursor is selected from a metal powder, an alkylated metal compound, a metal alkoxide, a metal carboxylate, a metal nitrate, a metal perchlorate, a metal sulfate, a metal acetylacetonate, a metal halide, a metal cyanide, a metal hydroxide, a metal oxide, a metal peroxide, and a combination thereof, and
wherein the non-metal precursor is a compound comprising an element selected from a Group V element, a Group VI element, and a combination thereof.

5. The process of claim 4 , wherein the metal precursor is selected from dimethyl zinc, diethyl zinc, zinc acetate, zinc acetylacetonate, zinc iodide, zinc bromide, zinc chloride, zinc fluoride, zinc carbonate, zinc cyanide, zinc nitrate, a zinc oxide, zinc peroxide, zinc perchlorate, zinc sulfate, dimethyl cadmium, diethyl cadmium, cadmium acetate, cadmium acetylacetonate, cadmium iodide, cadmium bromide, cadmium chloride, cadmium fluoride, cadmium carbonate, cadmium nitrate, cadmium oxide, cadmium perchlorate, cadmium phosphide, cadmium sulfate, mercury acetate, mercury iodide, mercury bromide, mercury chloride, mercury fluoride, mercury cyanide, mercury nitrate, mercury oxide, mercury perchlorate, mercury sulfate, lead acetate, lead bromide, lead chloride, lead fluoride, lead oxide, lead perchlorate, lead nitrate, lead sulfate, lead carbonate, tin acetate, tin bis(acetylacetonate), tin bromide, tin chloride, tin fluoride, tin oxide, tin sulfate, germanium tetrachloride, germanium oxide, germanium ethoxide, trimethyl gallium, triethyl gallium, gallium acetylacetonate, gallium-3-chloride, gallium fluoride, gallium oxide, gallium nitrate, gallium sulfate, trimethyl indium, indium acetate, indium hydroxide, indium chloride, indium oxide, indium nitrate, indium sulfate, thallium acetate, thallium acetylacetonate, thallium chloride, thallium oxide, thallium ethoxide, thallium nitrate, thallium sulfate, thallium carbonate, and a combination thereof, and
the non-metal precursor is selected from hexanethiol, octanethiol, decanethiol, dodecanethiol, hexadecanethiol, mercaptopropylsilane, sulfur-trioctylphosphine, sulfur-tributylphosphine, sulfur-triphenylphosphine, sulfur-trioctylamine, trimethylsilylsulfur, ammonium sulfide, sodium sulfide, selenium-trioctylphosphine, selenium-tributylphosphine, selenium-triphenylphosphine, tellurium-tributylphosphine, tellurium-triphenylphosphine, tris(trimethylsilyl)phosphine, tris(dimethylamino)phosphine, triethylphosphine, tributylphosphine, trioctylphosphine, triphenylphosphine, tricyclohexylphosphine, arsenic oxide, arsenic chloride, arsenic sulfate, arsenic bromide, arsenic iodide, nitric oxide, nitric acid, ammonium nitrate, and a combination thereof.

6. The process of claim 1 , wherein the ligand compound comprises a compound having a formula selected from RCOOH, RNH 2 , R 2 NH, R 3 N, RSH, R 3 PO, R 3 P, ROH, and RCOOR′, and a combination thereof, wherein R and R′ are each independently selected from a C1 to C24 alkyl group, a C5 to C20 aryl group, and a combination thereof.

7. The process of claim 1 , wherein the ionic liquid is selected from a substituted or unsubstituted imidazolium salt, a substituted or unsubstituted pyrazolium salt, a substituted or unsubstituted triazolium salt, a substituted or unsubstituted thiazolium salt, a substituted or unsubstituted oxazolium salt, a substituted or unsubstituted pyridazinium salt, a substituted or unsubstituted pyrimidinium salt, a substituted or unsubstituted ammonium salt, a substituted or unsubstituted phosphonium salt, a substituted or unsubstituted sulfonium salt, a substituted or unsubstituted pyridinium salt, a substituted or unsubstituted pyrrolidinium salt, and a combination thereof,
wherein the ionic liquid comprises a halide anion, tetrafluoroborate anion, hexafluorophosphate anion, perchlorate anion, acetate anion, trifluoroacetate anion, triflate anion, hydrogen sulfate anion, alkyl sulfate anion, sulphite anion, hydrogen sulphite anion, chloroaluminate anion, tetrabromoaluminate anion, nitrite anion, nitrate anion, dichlorocuprate anion, phosphate anion, hydrogen phosphate anion, dihydrogen phosphate anion, carbonate anion, hydrogen carbonate anion, sulfonate anion, tosylate anion, bis(trifluoromethyl sulphonyl)imide anion, or a combination thereof.

8. The process of claim 1 , wherein an amount of the ionic liquid is less than or equal to about 40 volume percent, based on a total volume of the organic solvent.

9. The process of claim 1 , wherein the mixture further comprises a protic solvent.

10. The process of claim 9 , wherein the protic solvent is included in an amount of greater than or equal to about 0.01 times a total volume of the ionic liquid.

11. The process of claim 9 , wherein the protic solvent is selected from an amine having 6 or more carbon atoms, an alcohol having 6 or more carbon atoms, and a combination thereof.

12. The process of claim 11 , wherein the amine is selected from a monoamine, a diamine, a triamine, and a combination thereof, and wherein the alcohol is selected from a monoalcohol, a dialcohol, a trialcohol, a polyol, and a combination thereof.

13. The process of claim 1 , wherein the heating the mixture comprises heating the mixture without irradiation of microwaves.

14. The process of claim 13 , wherein the heating comprises heating at a temperature of about 250° C. or less.

15. The process of claim 1 , wherein the core-shell nanocrystal has a quantum yield of about 50% or higher.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Jang Hyo Sook
• Jang Eun Joo
• Jun Shin Ae

Classifications

• C09K11/0811

  with zinc or cadmium · CPC title

• C30B7/14

  the crystallising materials being formed by chemical reactions in the solution · CPC title

• C09K11/56

  containing sulfur · CPC title

• C09K11/0805

  Chalcogenides · CPC title

• C30B29/40

  AIIIBV compounds {wherein A is B, Al, Ga, In or Tl and B is N, P, As, Sb or Bi} · CPC title