Light emitting element, ink composition and display device including the light emitting element

Patent metadata

Field	Value
Publication number	US-2025063885-A1
Application number	US-202418750963-A
Country	US
Kind code	A1
Filing date	Jun 21, 2024
Priority date	Aug 16, 2023
Publication date	Feb 20, 2025
Grant date	—

Abstract

A light emitting element of an embodiment includes a first electrode, a hole transport region on the first electrode, an emission layer on the hole transport region, an electron transport region on the emission layer, and a second electrode on the electron transport region, the electron transport region includes a nanoparticle including a nanoparticle core and a ligand, the nanoparticle core includes a core compound represented by Formula 1, and the ligand is bonded to the surface of the nanoparticle core and represented by Formula 2 or Formula 3.

First claim

What is claimed is:

1 . A light emitting element, comprising:
a first electrode; a hole transport region on the first electrode; an emission layer on the hole transport region; an electron transport region on the emission layer; and a second electrode on the electron transport region, wherein the electron transport region comprises a nanoparticle comprising a nanoparticle core, and a ligand, the nanoparticle core comprises a core compound represented by the following Formula 1, and the ligand is bonded to the surface of the nanoparticle core, and represented by the following Formula 2 or Formula 3:

in Formula 1,
A is Zn, or Sn, and
“x”, and “y” are each independently an integer of 1 to 5, in Formula 2,
M is one among Li, Na, K, Rb, Cs, Be, Ca, Sr, and Ba,
R 1 is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group of 2 to 20 carbon atoms, a substituted or unsubstituted aryl group of 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group of 2 to 30 ring-forming carbon atoms,
“a” is an integer of 0 to 3, and
“ ”, and

are each a position connected with the nanoparticle core, and
in Formula 3,
R2 is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group of 2 to 20 carbon atoms, a substituted or unsubstituted aryl group of 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group of 2 to 30 ring-forming carbon atoms,
M is the same as defined with respect to Formula 2,
“b” is an integer of 0 to 3, and
“ ” is a position connected with the nanoparticle core.

2 . The light emitting element of claim 1 , wherein:
the electron transport region comprises: an electron transport layer on the emission layer; and an electron injection layer on the electron transport layer, and the electron transport layer comprises the nanoparticle.

3 . The light emitting element of claim 1 , wherein the nanoparticle core is doped with a metal element.

4 . The light emitting element of claim 3 , wherein the metal element is at least one among Zn, Mg, Li, Na, Ni, and Cu.

5 . The light emitting element of claim 1 , wherein the emission layer comprises a quantum dot.

6 . The light emitting element of claim 1 , wherein, in Formula 1, “x” is 1, and “y” is 2.

7 . The light emitting element of claim 1 , wherein:
in Formula 1, “A” is Sn, and in Formula 2 and Formula 3, M is Ca.

8 . The light emitting element of claim 1 , wherein:
if the ligand is represented by Formula 2, R 1 is a substituted or unsubstituted alkyl group of 1 to 5 carbon atoms, and if the ligand is represented by Formula 3, R 2 is a substituted or unsubstituted alkyl group of 1 to 5 carbon atoms.

9 . The light emitting element of claim 1 , wherein:
if the ligand is represented by Formula 2, R 1 is a substituted or unsubstituted alkyl group of 6 to 20 carbon atoms, and if the ligand is represented by Formula 3, R 2 is a substituted or unsubstituted alkyl group of 6 to 20 carbon atoms.

10 . An ink composition comprising:
a nanoparticle core comprising a core compound represented by the following Formula 1; a preliminary ligand represented by the following Formula 4; and a solvent in which the nanoparticle core and the preliminary ligand are dispersed:

in Formula 1,
A is Zn, or Sn, and
“x”, and “y” are each independently an integer of 1 to 5,
in Formula 4,
M is one among Li, Na, K, Rb, Cs, Be, Ca, Sr, and Ba,
R 3 and R 4 are each independently a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group of 2 to 20 carbon atoms, a substituted or unsubstituted aryl group of 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group of 2 to 30 ring-forming carbon atoms, and
“c” and “d” are each independently an integer of 0 to 3.

11 . The ink composition of claim 10 , wherein, in Formula 4, R 3 and R 4 are each independently a substituted or unsubstituted alkyl group of 1 to 5 carbon atoms.

12 . The ink composition of claim 11 , wherein the solvent comprises a water-soluble solvent.

13 . The ink composition of claim 12 , wherein a weight ratio of the nanoparticle core to the water-soluble solvent is about 1% to about 10%.

14 . The ink composition of claim 12 , wherein the water-soluble solvent comprises a first solvent compound represented by the following Formula 5:

in Formula 5,
R 11 and R 12 are each independently a substituted or unsubstituted alkylene group of 1 to 4 carbon atoms,
R 13 is a substituted or unsubstituted alkyl group of 1 to 4 carbon atoms, and “t” is 1 or 2.

15 . The ink composition of claim 14 , wherein the first solvent compound comprises at least one among diethylene glycol t-butyl ether (DGtBE), tripropylene glycol monobutyl ether (TPGBE), and triethylene glycol monoisopropyl ether (TGIPE).

16 . The ink composition of claim 10 , wherein, in Formula 4, R 3 and R 4 are each independently a substituted or unsubstituted alkyl group of 6 to 20 carbon atoms.

17 . The ink composition of claim 16 , wherein the solvent comprises at least one among cyclohexylbenzene (CHB) and hexadecane.

18 . A display device comprising:
a base layer; a circuit layer on the base layer; and a display element layer on the circuit layer and comprising a light emitting element, wherein: the light emitting element comprises a first electrode, a second electrode on the first electrode, and an electron transport region between the first electrode and the second electrode, the electron transport region comprises a nanoparticle comprising a nanoparticle core, and a ligand, the nanoparticle core comprises a core compound represented by the following Formula 1, and the ligand is bonded to the surface of the nanoparticle core and represented by the following Formula 2 or Formula 3:

in Formula 1,
A is Zn, or Sn, and
“x”, and “y” are each independently an integer of 1 to 5, in Formula 2,
M is one among Li, Na, K, Rb, Cs, Be, Ca, Sr, and Ba,
R 1 is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group of 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group of 2 to 20 carbon atoms, a substituted or unsubstituted aryl group of 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group of 2 to 30 ring-forming carbon atoms,
“a” is an integer of 0 to 3, and
“ ”, and

are each a position connected with the nanoparticle core, and
in Formula 3,
R 2 is a hydrogen atom, a deuter

Assignees

• Samsung Display Co Ltd

Inventors

• Jung Yunku
• Lee Sooho
• Jo Jungho
• Han Chang Yeol
• Ko Yunhyuk
• Kim Sehun

Classifications

• B82Y30/00

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

• H10K59/12

  Active-matrix OLED [AMOLED] displays · CPC title

• H10K50/16 Primary

  Electron transporting layers · CPC title

• H10K59/1213

  the pixel elements being TFTs · CPC title

• H10K50/171

  Electron injection layers · CPC title