Quantum dots, quantum dot-polymer composite, and electronic device including the same

Patent metadata

Field	Value
Publication number	US-11753589-B2
Application number	US-202117383814-A
Country	US
Kind code	B2
Filing date	Jul 23, 2021
Priority date	Jul 23, 2020
Publication date	Sep 12, 2023
Grant date	Sep 12, 2023

Abstract

A quantum dot, a quantum dot-polymer composite, and an electronic device including the same. The quantum dot includes a core including a first semiconductor nanocrystal; a first shell including a second semiconductor nanocrystal including a Group III-VI compound on the core; and a second shell including a third semiconductor nanocrystal having a composition different from that of the second semiconductor nanocrystal on the first shell; wherein one of the first semiconductor nanocrystal and the third semiconductor nanocrystal includes a Group III-V compound.

First claim

What is claimed is:

1. A quantum dot, comprising
a core comprising a first semiconductor nanocrystal;
a first shell comprising a second semiconductor nanocrystal comprising a Group III-VI compound disposed on the core; and
a second shell comprising a third semiconductor nanocrystal having a composition different from that of the second semiconductor nanocrystal on the first shell;
wherein one of the first semiconductor nanocrystal and the third semiconductor nanocrystal comprises a Group III-V compound, and
in the quantum dot, a mole ratio of a Group III element of the Group III-V compound and Group III-VI compound to a Group V element is about 1:1 to about 50:1.

2. The quantum dot of claim 1 , wherein
one of the first semiconductor nanocrystal and the third semiconductor nanocrystal comprises a Group III-V compound, and
the other comprises a Group II-VI compound.

3. The quantum dot of claim 2 , wherein
the first semiconductor nanocrystal comprises a Group III-V compound and the third semiconductor nanocrystal comprises a Group II-VI compound,
wherein a ratio of an effective mass of the second semiconductor nanocrystal relative to an effective mass of the third semiconductor nanocrystal is greater than or equal to about 0.4:1 to about 2.5:1.

4. The quantum dot of claim 2 , wherein the Group II-VI compound comprises a zinc chalcogenide.

5. The quantum dot of claim 2 , wherein the Group II-VI compound comprises ZnSe, ZnTeSe, ZnSeS, ZnTeS, ZnS, or a combination thereof.

6. The quantum dot of claim 2 , wherein the Group II-VI compound comprises zinc, sulfur, and selenium or zinc, selenium, and tellurium.

7. The quantum dot of claim 2 , wherein in the quantum dot, a mole ratio of e Group III element to the Group II element is greater than about 0:1 and less than or equal to about 5:1.

8. The quantum dot of claim 2 , wherein in the quantum dot, a mole ratio of the Group III element to the Group II element is about 0.05:1 to about 2:1.

9. The quantum dot of claim 1 , wherein the second semiconductor nanocrystal has an electron effective mass of less than about 0.39 m e .

10. The quantum dot of claim 1 , wherein the second semiconductor nanocrystal has a hole effective mass of less than about 1.76 m e .

11. The quantum dot of claim 1 , wherein
the first semiconductor nanocrystal comprises a Group III-V compound and the third semiconductor nanocrystal comprises a Group II-VI compound,
wherein a difference between an electron effective mass of the second semiconductor nanocrystal and an electron effective mass of the third semiconductor nanocrystal is less than or equal to about 0.2 m e .

12. The quantum dot of claim 1 , wherein
the first semiconductor nanocrystal comprises a Group III-V compound and the third semiconductor nanocrystal comprises a Group II-VI compound,
wherein a difference between a hole effective mass of the second semiconductor nanocrystal and a hole effective mass of the third semiconductor nanocrystal is less than or equal to about 1.5 m e .

13. The quantum dot of claim 1 , wherein the Group III-V compound further comprises a Group II element.

14. The quantum dot of claim 1 , wherein the Group III-V compound comprises InP, GaP, InAs, GaAs, InSb, GaSb, InGaP, InAsP, InSbP, InGaAs, InZnP, GaZnP, InZnAs, or a combination thereof.

15. The quantum dot of claim 1 , wherein the second semiconductor nanocrystal comprises gallium.

16. The quantum dot of claim 1 , wherein the second semiconductor nanocrystal comprises a gallium chalcogenide.

17. The quantum dot of claim 1 , wherein the second semiconductor nanocrystal comprises a compound represented by
(M 1 ) 2 (X 1 ) 3 , herein M 1 is In, Ga, or a combination thereof, and X 1 is S, Se, Te, or a combination thereof, a compound represented by Chemical Formula 1, or a combination thereof:
(M 2 2-x M 3 x )(X 2 3-y X 3 y )  Chemical Formula 1

wherein, in Chemical Formula 1,
M 2 and M 3 are each independently In, Ga, or a combination thereof, X 2 and X 3 are each independently S, Se, Te, or a combination thereof, x is 0 to 2, and y is 0 to 3.

18. The quantum dot of claim 1 , wherein in the quantum dot, a mole ratio of the Group III element to the Group V element is about 2.5:1 to about 20:1.

19. The quantum dot of claim 1 , wherein in the quantum dot, a mole ratio of the Group III element to the Group VI element is greater than about 0:1 and less than or equal to about 5:1.

20. The quantum dot of claim 1 , wherein in the quantum dot, a mole ratio of the Group III element to the Group VI element is about 0.05:1 to about 2:1.

21. The quantum dot of claim 1 , wherein in the quantum dot, the first semiconductor nanocrystal comprises indium, the second semiconductor nanocrystal comprises gallium, and a mole ratio of gallium to indium is about 0.05:1 to about 4.5:1.

22. The quantum dot of claim 1 , wherein the second shell comprises a Group II-VI compound, a Group III-V compound, or a combination thereof.

23. The quantum dot of claim 1 , wherein a lattice mismatch of the first semiconductor nanocrystal and the second semiconductor nanocrystal is less than or equal to about 15%.

24. The quantum dot of claim 1 , wherein a maximum emission peak of the quantum dots has a full width at half maximum of less than or equal to about 40 nanometers.

25. The quantum dot of claim 1 , wherein the quantum dot has a quantum efficiency of greater than or equal to about 55%.

26. The quantum dot of claim 1 , wherein
the first semiconductor nanocrystal comprising indium and phosphorus;
the second semiconductor nanocrystal comprising gallium and sulfur; and
the third semiconductor nanocrystal comprising zinc and sulfur; zinc and selenium; or a combination thereof.

27. A quantum dot, comprising
a core comprising a first semiconductor nanocrystal;
a first shell comprising a second semiconductor nanocrystal comprising a Group III-VI compound disposed on the core; and
a second shell comprising a third semiconductor nanocrystal having a composition different from that of the second semiconductor nanocrystal on the first shell;
wherein one of the first semiconductor nanocrystal and the third semiconductor nanocrystal comprises a Group III-V compound,
the second shell comprises a plurality of layers, and
the plurality of layers comprises different Group II-VI compounds.

28. The quantum dot of claim 27 , wherein a layer closest to the core among the plurality of layers comprises Se.

29. The quantum dot of claim 27 , wherein a layer disposed farthest from the core among the plurality of layers comprises S.

30. A quantum dot, comprising
a core comprising a first semiconductor nanocrystal;
a first shell comprising a second semiconductor nanocrystal comprising a Group III-VI compound disposed on the core; and
a second shell comprising a third semiconductor nanocrystal having a composition different from that of the second semiconductor nanocrystal on the first shell;
wherein one of the first semiconductor nanocrystal and the third semiconductor nanocrystal comprises a Group III-V compound,
a bandgap energy of the second semiconductor nanocrystal is greater than a bandgap energy of the first semiconductor nanocrystal, and
the bandgap energy of the second semiconductor nanocrystal is greater than a bandgap energy of the third semiconductor nanoc

Assignees

• Samsung Electronics Co Ltd

Inventors

• MIN Jihyun
• Jang Eun Joo
• Kim Yong Wook

Classifications

• H10F10/00

  Individual photovoltaic cells, e.g. solar cells (electrolytic light-sensitive devices, e.g. dye-sensitised solar cells, H01G9/20) · CPC title

• H10F77/1433

  Quantum dots · CPC title

• C09K11/02 Primary

  Use of particular materials as binders, particle coatings or suspension media therefor · CPC title

• C09K11/025 Primary

  non-luminescent particle coatings or suspension media · CPC title

• C09K11/883 Primary

  with zinc or cadmium · CPC title