Semiconductor nanocrystals

Patent metadata

Field	Value
Publication number	US-10276735-B2
Application number	US-201715660930-A
Country	US
Kind code	B2
Filing date	Jul 26, 2017
Priority date	Jan 23, 2008
Publication date	Apr 30, 2019
Grant date	Apr 30, 2019

Abstract

A semiconductor nanocrystal include a first I-III-VI semiconductor material and have a luminescence quantum yield of at least 10%, at least 20%, or at least 30%. The nanocrystal can be substantially free of toxic elements. Populations of the nanocrystals can have an emission FWHM of no greater than 0.35 eV.

First claim

What is claimed is:

1. A semiconductor nanocrystal comprising a core including a first IB-IIIA-VIA semiconductor material, wherein the nanocrystal has a luminescence quantum yield of at least 20%, wherein the nanocrystal has a peak luminescence emission wavelength in the range of 540 nm to no more than 975 nm,
wherein the nanocrystal is a member of a nanocrystal population having an emission FWHM of no greater than 0.35 eV,
wherein the group IB element is copper and the group IIIA element is indium, and the IB-IIIA-VIA semiconductor material is not CuInGaS 2 .

2. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal has a luminescence quantum yield of at least 30%.

3. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal does not contain gallium.

4. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal does not include sulfur.

5. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal is a member of a nanocrystal population having an emission FWHM of no greater than 0.2 eV.

6. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material includes a smaller molar amount of copper than indium.

7. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material includes copper and indium in a ratio of less than 1:2.

8. The semiconductor nanocrystal of claim 1 , wherein the group VIA element is sulfur.

9. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal is a member of a nanocrystal population having a deviation from mean radius of no greater than 15% rms.

10. The semiconductor nanocrystal of claim 1 , wherein the core further includes a group IIB element.

11. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material is a copper indium selenide or a copper indium gallium selenide.

12. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material is an alloy with zinc sulfide.

13. The semiconductor nanocrystal of claim 12 , wherein the alloy with zinc sulfide forms a core shell structure.

14. The semiconductor nanocrystal of claim 1 , further comprising an overcoating on a surface of the core, the overcoating including a second semiconductor material.

15. The semiconductor nanocrystal of claim 1 , further comprising a ligand on a surface of the semiconductor nanocrystal.

16. The semiconductor nanocrystal of claim 14 , wherein the second semiconductor nanocrystal is water soluble.

17. The semiconductor nanocrystal of claim 1 , wherein the core of the nanocrystal has a radius between 1 nm and 10 nm.

18. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal has a radius between 2 nm and 4 nm.

19. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal has a radius between 2.2 nm and 2.7 nm.

20. The semiconductor nanocrystal of claim 1 , wherein molar amount of the IIIA element is more than the molar amount of the IB element.

21. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material is a copper indium selenide.

22. The semiconductor nanocrystal of claim 1 , wherein the first IB-IIIA-VIA semiconductor material is a copper indium gallium selenide.

23. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal has a peak luminescence emission wavelength in the range of 530-670 nm.

24. The semiconductor nanocrystal of claim 1 , wherein the nanocrystal has a peak luminescence emission wavelength in the range of 800-975 nm.

25. A semiconductor nanocrystal comprising a core including a first IB-IIIA-VIA semiconductor material, wherein the nanocrystal has a luminescence quantum yield of at least 20%, wherein the nanocrystal is a member of a nanocrystal population having a deviation from mean size of no greater than 25% rms, wherein the nanocrystal has a peak luminescence emission wavelength in the range of 540 nm to no more than 975 nm, wherein the core of the nanocrystal has a radius between 1 nm and 10 nm;
and
wherein the nanocrystal is a member of a nanocrystal population having an emission FWHM of no greater than 0.35 eV,
wherein the group IB element is silver, and the IB-IIIA-VIA semiconductor material is not CuInGaS 2 .

26. The semiconductor nanocrystal of claim 25 , wherein the first IB-IIIA-VIA semiconductor material is a silver indium selenide.

27. A semiconductor nanocrystal comprising a IB-IIIA-VIA semiconductor material, wherein the nanocrystal has a luminescence quantum yield of at least 20%, wherein the nanocrystal has a peak luminescence emission wavelength in the range of 540 nm to no more than 975 nm,
wherein the group IB element is copper, the group IIIA element is indium, and the group VIA element is sulfur, and the IB-IIIA-VIA semiconductor material is not CuInGaS 2 .

28. The semiconductor nanocrystal of claim 27 , wherein the nanocrystal has a peak luminescence emission wavelength in the range of 530-760 nm.

29. The semiconductor nanocrystal of claim 27 , wherein the nanocrystal has a peak luminescence emission wavelength in the range of 780-975 nm.

30. The semiconductor nanocrystal of claim 27 , wherein the first IB-IIIA-VIA semiconductor material includes a smaller molar amount of copper than indium.

Assignees

• Massachusetts Inst Technology

Inventors

• Allen Peter Matthew
• Bawendi Moungi G

Classifications

• Y02P70/521

  Cross-Sectional Technologies · mapped topic

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title

• Y02E10/541

  CuInSe2 material PV cells · CPC title

• C09K11/58

  containing copper, silver or gold · CPC title

• C09K11/584

  with zinc or cadmium · CPC title