Blue electroluminescent device, display panel and display device

Patent metadata

Field	Value
Publication number	US-12167616-B2
Application number	US-202117364625-A
Country	US
Kind code	B2
Filing date	Jun 30, 2021
Priority date	Aug 21, 2020
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A blue electroluminescent device includes: an anode, a light-emitting layer and a cathode stacked in sequence; wherein the light-emitting layer comprises a first type host material, a second type host material, and a guest doped material, one of the first type host material and the second type host material is a P-type material, and the other of the first type host material and the second type host material is an N-type material. A display panel and a display device are further provided.

First claim

The invention claimed is:

1. A blue electroluminescent device comprising: an anode, a light-emitting layer and a cathode stacked in sequence;
wherein the light-emitting layer comprises a first type host material, a second type host material, and a guest doped material, one of the first type host material and the second type host material is a P-type material, and the other of the first type host material and the second type host material is an N-type material;
wherein the P-type material comprises at least one of

2. The blue electroluminescent device according to claim 1 , wherein a Lowest Unoccupied Molecular Orbital (LUMO) energy level of the N-type material is not less than 2.1 eV and not greater than 3.3 eV; a Highest Occupied Molecular Orbital (HOMO) energy level of the P-type material is not less than 5.5 eV and not more than 6.5 eV; a difference between the HOMO energy level of the P-type material and the LUMO energy level of the N-type material is not less than 2.6 eV.

3. The blue electroluminescent device according to claim 1 , wherein a mole ratio of the P-type material to the N-type material ranges from 1:4 to 4:1.

4. The blue electroluminescent device according to claim 1 , wherein a hole mobility of the P-type material ranges from 10 −8 cm 2 /(V·s) to 10 −4 cm 2 /(V·s), and an electron mobility of the N-type material ranges from 10 −8 cm 2 /(V·s) to 10 −4 cm 2 /(V·s).

5. A blue electroluminescent device comprising: an anode, a light-emitting layer and a cathode stacked in sequence;
wherein the light-emitting layer comprises a first type host material, a second type host material, and a guest doped material, one of the first type host material and the second type host material is a P-type material, and the other of the first type host material and the second type host material is an N-type material, wherein the N-type material comprises at least one of

6. The blue electroluminescent device according to claim 1 , wherein the cathode is formed of Mg and Ag, a mole ratio of Mg to Ag ranges from 1:9 to 9:1, and a thickness of the cathode ranges from 10 nm to 100 nm.

7. A blue electroluminescent device comprising: an anode, a light-emitting layer and a cathode stacked in sequence;
wherein the light-emitting layer comprises a first type host material, a second type host material, and a guest doped material, one of the first type host material and the second type host material is a P-type material, and the other of the first type host material and the second type host material is an N-type material, further comprising:
a hole transport layer, disposed between the anode and the light-emitting layer;
a hole injection layer, disposed between the anode and the hole transport layer;
an electron blocking layer, disposed between the hole transport layer and the light-emitting layer;
an electron transport layer, disposed between the cathode and the light-emitting layer;
an electron injection layer, disposed between the cathode and the electron transport layer; and
a hole blocking layer, disposed between the electron transport layer and the light-emitting layer;
wherein a difference between an absolute value of a HOMO energy level of the P-type material and an absolute value of a HOMO energy level of the electron blocking layer is not greater than 0.3 eV; and
a difference between an absolute value of a LUMO energy level of the hole blocking layer and an absolute value of a LUMO energy level of the N-type material is not more than 0.3 eV.

8. The blue electroluminescent device according to claim 7 , wherein a thickness of the hole injection layer ranges from 8 nm to 12 nm, a thickness of the hole transport layer ranges from 100 nm to 120 nm, and a thickness of the electron blocking layer ranges from 3 nm to 7 nm, a thickness of the light-emitting layer ranges from 15 nm to 25 nm, a thickness of the hole blocking layer ranges from 3 nm to 7 nm, a thickness of the electron transport layer ranges from 25 nm to 35 nm, and a thickness of the electron injection layer ranges from 1 nm to 2 nm.

9. The blue electroluminescent device according to claim 1 , further comprising:
a hole transport layer, disposed between the anode and the light-emitting layer;
a hole injection layer, disposed between the anode and the hole transport layer;
an electron blocking layer, disposed between the hole transport layer and the light-emitting layer;
an electron transport layer, disposed between the cathode and the light-emitting layer;
an electron injection layer, disposed between the cathode and the electron transport layer; and
a hole blocking layer, disposed between the electron transport layer and the light-emitting layer.

10. The blue electroluminescent device according to claim 9 , wherein a difference between an absolute value of a HOMO energy level of the P-type material and an absolute value of a HOMO energy level of the electron blocking layer is not greater than 0.3 eV; and
a difference between an absolute value of a LUMO energy level of the hole blocking layer and an absolute value of a LUMO energy level of the N-type material is not more than 0.3 eV.

11. The blue electroluminescent device according to claim 9 , wherein a thickness of the hole injection layer ranges from 8 nm to 12 nm, a thickness of the hole transport layer ranges from 100 nm to 120 nm, and a thickness of the electron blocking layer ranges from 3 nm to 7 nm, a thickness of the light-emitting layer ranges from 15 nm to 25 nm, a thickness of the hole blocking layer ranges from 3 nm to 7 nm, a thickness of the electron transport layer ranges from 25 nm to 35 nm, and a thickness of the electron injection layer ranges from 1 nm to 2 nm.

12. The blue electroluminescent device of claim 5 , further comprising:
a hole transport layer, disposed between the anode and the light-emitting layer;
a hole injection layer, disposed between the anode and the hole transport layer;
an electron blocking layer, disposed between the hole transport layer and the light-emitting layer;
an electron transport layer, disposed between the cathode and the light-emitting layer;
an electron injection layer, disposed between the cathode and the electron transport layer; and
a hole blocking layer, disposed between the electron transport layer and the light-emitting layer.

13. The blue electroluminescent device according to claim 12 , wherein a difference between an absolute value of a HOMO energy level of the P-type material and an absolute value of a HOMO energy level of the electron blocking layer is not greater than 0.3 eV; and
a difference between an absolute value of a LUMO energy level of the hole blocking layer and an absolute value of a LUMO energy level of the N-type material is not more than 0.3 eV.

14. The blue electroluminescent device according to claim 12 , wherein a thickness of the hole injection layer ranges from 8 nm to 12 nm, a thickness of the hole transport layer ranges from 100 nm to 120 nm, and a thickness of the electron blocking layer ranges from 3 nm to 7 nm, a thickness of the light-emitting layer ranges from 15 nm to 25 nm, a thickness of the hole blocking layer ranges from 3 nm to 7 nm, a thickness of the electron transport layer ranges from 25 nm to 35 nm, and a thickness of the electron injection layer ranges from 1 nm to 2 nm.

15. The blue electroluminescent device of claim 6 , further comprising:
a hole transport layer, disposed between

Assignees

• Boe Technology Group Co Ltd
• Beijing Boe Technology Dev Co Ltd

Inventors

• Liu Yang
• Qiu Lixia
• Chen Chuang

Classifications

• H10K2101/40

  Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers · CPC title

• H10K50/171

  Electron injection layers · CPC title

• H10K50/16

  Electron transporting layers · CPC title

• H10K50/15

  Hole transporting layers · CPC title

• H10K50/11 Primary

  characterised by the electroluminescent [EL] layers · CPC title