Quantum dot composition including a ligand bonded to a surface of a quantum dot, light emitting element including an emission layer containing a quantum dot and ligand residues, and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-11866627-B2
Application number	US-202117192388-A
Country	US
Kind code	B2
Filing date	Mar 4, 2021
Priority date	Jun 2, 2020
Publication date	Jan 9, 2024
Grant date	Jan 9, 2024

Abstract

A quantum dot composition includes a quantum dot, and a ligand bonded to a surface of the quantum dot, wherein the ligand includes a head portion bonded to the surface of the quantum dot and containing a polar solvent dissociative functional group, and a tail portion connected to the head portion. A quantum dot composition according to an embodiment is used to form an emission layer of a light emitting element to enhance luminous efficiency of the light emitting element including an emission layer formed through the quantum dot composition.

First claim

What is claimed is:

1. A quantum dot composition comprising:
a quantum dot; and
a ligand bonded to a surface of the quantum dot,
wherein the ligand comprises:
a head portion bonded to the surface of the quantum dot and containing a polar solvent dissociative functional group; and
a tail portion connected to the head portion, the tail portion containing a non-polar organic material, and

the ligand is represented by any one among Formulae 1 to 19, and 21 to 23:

wherein in Formulae 1 to 19, and 21 to 23,
R 1 and R 2 are each independently a substituted or unsubstituted alkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, and
x 1 is an integer of 1 to 10.

2. The quantum dot composition of claim 1 , wherein the quantum dot comprises:
a core; and
a shell surrounding the core, and
an interface between the core and the shell having a concentration gradient of an element that decreases toward the core.

3. The quantum dot composition of claim 1 , wherein the tail portion comprises a substituted or unsubstituted alkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms.

4. The quantum dot composition of claim 1 , wherein the ligand is a monodentate ligand or a bidentate ligand.

5. The quantum dot composition of claim 1 , wherein the head portion comprises a hydrogen cation, a sodium cation, or a potassium cation.

6. The quantum dot composition of claim 1 , further comprising a non-polar organic solvent.

7. The quantum dot composition of claim 1 , wherein the tail portion has a first end connected to the head portion and a free second end opposite the first end.

8. A light emitting element comprising:
a first electrode;
a hole transport region on the first electrode;
an emission layer on the hole transport region and containing a quantum dot and ligand residues, the ligand residues comprising a head portion and a tail portion connected to the head portion, the tail portion containing a non-polar organic material;
an electron transport region on the emission layer; and
a second electrode on the electron transport region, and
wherein the head portion comprises a polar solvent dissociative functional group, and
the ligand residues are dissociated from the quantum dots.

9. The light emitting element of claim 7 , wherein the quantum dot comprises:
a core; and
a shell surrounding the core, and
an interface between the core and the shell having a concentration gradient of an element that decreases toward the core.

10. The light emitting element of claim 7 , wherein
the ligand residues comprise at least one among a sulfonyl ion, a carbonyl ion, a phosphate ion, an ammonium ion, an oxy group, or an amine group.

11. The light emitting element of claim 7 , wherein
the ligand residues comprise a substituted or unsubstituted alkyl group having 6 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms.

12. The light emitting element of claim 7 , wherein the ligand residues comprise a hydrogen cation, a sodium cation, or a potassium cation.

13. The light emitting element of claim 7 , wherein the ligand residues comprise aliphatic or aromatic hydrocarbons connected to the polar solvent dissociative functional group.

Assignees

• Samsung Display Co Ltd

Inventors

• Lee Changhee
• Kim Dukki
• Ko Hyojin
• Kim Sehun
• Kim Jaehoon
• Doh Hyunmi
• Jung Yunku
• Ha Jaekook

Classifications

• H10K71/441

  in the presence of solvent vapors, e.g. solvent vapour annealing · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title

• C07C43/10

  of polyhydroxy compounds · CPC title

• C07C53/00

  Saturated compounds having only one carboxyl group bound to an acyclic carbon atom or hydrogen · CPC title

• C07C63/08

  Salts thereof · CPC title