Light emitting nanocrystals and methods of making light emitting nanocrystals

Patent metadata

Field	Value
Publication number	US-12441939-B2
Application number	US-202017086285-A
Country	US
Kind code	B2
Filing date	Oct 30, 2020
Priority date	Oct 31, 2019
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A composition can include a copper containing nanocrystal.

First claim

What is claimed is:

1. A plurality of nanocrystals having the formula:
Cu—Al—X 2 , where X is S or Se,

wherein the nanocrystals have a luminescence quantum yield of at least 10%.

2. The plurality of nanocrystals of claim 1 , further comprising a zinc sulfide over coating.

3. The plurality of nanocrystals of claim 1 , wherein the nanocrystals are doped with zinc.

4. The plurality of nanocrystals of claim 1 , wherein the nanocrystals have an emission of between 380 and 560 nm.

5. The plurality of nanocrystals of claim 1 , wherein the nanocrystals have an emission of between 420 and 550 nm.

6. The plurality of nanocrystals of claim 1 , wherein the nanocrystals have an emission efficiency of at least 10%.

7. The plurality of nanocrystals of claim 1 , wherein the nanocrystals have a size of between 2 nm and 20 nm.

8. The plurality of nanocrystals of claim 1 , wherein the nanocrystals have a size of between 3 nm and 10 nm.

9. The plurality of nanocrystals of claim 1 , wherein the nanocrystals are CuAlS 2 nanocrystals.

10. A method of making semiconductor nanocrystals comprising:
heating a first mixture including:
a first M donor including Cu; and
a second M donor including Al; and

adding a first E donor including a sulfur or selenium to the first mixture, thereby forming a population of nanocrystal cores having the formula:
Cu—Al—X 2 , where X is S or Se,

the semiconductor nanocrystals having a luminescence quantum yield of at least 10%.

11. The method of claim 10 , wherein the nanocrystals are defective nanocrystals.

12. The method of claim 10 , wherein:
the nanocrystals comprise CuAlS 2 , and
further comprising adding ZnS to the first mixture after the adding of the first E donor such that the nanocrystals are alloyed with ZnS.

13. A semiconductor nanocrystal comprising a core including a IB-IIIA-VIA semiconductor material, wherein:
the nanocrystal has a luminescence quantum yield of at least 10%,
the nanocrystal has a peak luminescence emission wavelength in the range of 380 nm to 560 nm,
the nanocrystal is a defective nanocrystal,
the group IB element is copper,
the group IIIA element is aluminum, and
the group VIA element is sulfur or selenium.

14. The semiconductor nanocrystal of claim 13 , wherein the nanocrystal is doped with zinc.

15. The semiconductor nanocrystal of claim 13 , wherein the nanocrystal includes a zinc sulfide shell over the core.

16. The semiconductor nanocrystal of claim 13 , wherein the IB-IIIA-VIA semiconductor material is CuAlS 2 or CuAl 5 S 8 .

Assignees

• Massachusetts Inst Technology

Inventors

• Bawendi Moungi
• Hansen Eric

Classifications

• C09K11/881

  Chalcogenides · CPC title

• C09K11/605

  with zinc or cadmium · CPC title

• B82Y40/00

  Manufacture or treatment of nanostructures · CPC title

• B82Y20/00

  Nanooptics, e.g. quantum optics or photonic crystals · CPC title

• C09K11/025

  non-luminescent particle coatings or suspension media · CPC title