Metal-assisted delayed fluorescent materials as co-host materials for fluorescent OLEDs

Patent metadata

Field	Value
Publication number	US-9920242-B2
Application number	US-201515505544-A
Country	US
Kind code	B2
Filing date	Aug 21, 2015
Priority date	Aug 22, 2014
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A light emitting device includes a first electrode, a hole transporting layer in contact with the first electrode, a second electrode, an electron transporting layer in contact with the second electrode; and an emissive layer between the hole transporting layer and the electron transporting layer. The emissive layer includes a metal-assisted delayed fluorescent (MADF) emitter, a fluorescent emitter, and a host, and the MADF emitter harvests electrogenerated excitons and transfers energy to the fluorescent emitter.

First claim

What is claimed is:

1. A light emitting device comprising:
a first electrode;
a hole transporting layer in contact with the first electrode;
a second electrode;
an electron transporting layer in contact with the second electrode; and
an emissive layer between the hole transporting layer and the electron transporting layer, the emissive layer comprising a metal-assisted delayed fluorescent (MADF) emitter, a fluorescent emitter, and a host, wherein the MADF emitter harvests electrogenerated excitons and transfers energy to the fluorescent emitter.

2. The light emitting device of claim 1 , wherein the emissive layer is a single layer comprising the host, the MADF emitter, and the fluorescent emitter.

3. The light emitting device of claim 1 , wherein the emissive layer comprises:
n emitter layers comprising the host and the fluorescent emitter; and
m donor layers comprising the host and the MADF emitter,
wherein n and m are integers ≥1.

4. The light emitting device of claim 3 , wherein n and m are equal.

5. The light emitting device of claim 3 , wherein each emitter layer is adjacent to at least one donor layer.

6. The light emitting device of claim 3 , wherein n=m+1, or m=n+1.

7. The light emitting device of claim 1 , wherein the light emitting device is a fluorescent organic light emitting device.

8. The light emitting device of claim 1 , wherein the MADF emitter is a five-membered or six-membered MADF emitter.

9. The light emitting device of claim 6 , wherein the MADF emitter is a compound of structure (a) or (b):

wherein:
M is platinum (II), palladium (II), nickel (II), manganese (II), zinc (II), gold (III), silver (III), copper (III), iridium (I), rhodium (I), or cobalt (I);
A is an accepting group having one of the following structures, which can optionally be substituted:

D is a donor group having one of the following structures, which can optionally be substituted:

C has one of the following structures, which can optionally be substituted:

N has one of the following structures, which can optionally be substituted:

each of a 0 , a 1 , and a 2 is independently present or absent, and if present, is a direct bond or linking group having one of the following structures:

each of b 1 and b 2 is independently present or absent, and if present, comprises a linking group comprising one or more of the following structures:

X is B, C, N, O, Si, P, S, Ge, As, Se, Sn, Sb, or Te;
Y is N, P, P═O, As, As═O, CH, CR, SiH, SiR, GeH, or GeR;
each R is independently hydrogen, deuterium, halogen, hydroxyl, thiol, nitro, cyano, nitrile, isonitrile, sulfinyl, mercapto, sulfo, carboxyl, hydrazino; substituted or unsubstituted: aryl, cycloalkyl, cycloalkenyl, heterocyclyl, heteroaryl, alkyl, alkenyl, alkynyl, amino, monoalkylamino, dialkylamino, monoarylamino, diarylamino, alkoxy, aryloxy, haloalkyl, aralkyl, ester, alkoxycarbonyl, acylamino, alkoxycarbonylamino, aryloxycarbonylamino, sulfonylamino, sulfamoyl, carbamoyl, alkylthio, ureido, phosphoramide, silyl, polymeric, or any conjugate or combination thereof; and
n is an integer that satisfies the valency of Y.

10. The light emitting device of claim 9 , wherein a 2 is absent.

11. The light emitting device of claim 9 , wherein a 2 and b 2 are absent.

12. The light emitting device of claim 9 , wherein X is N.

13. The light emitting device of claim 9 , wherein A is

a 2 is absent, b 2 is absent, and D is

14. The light emitting device of claim 9 , wherein C in structure (a) or (b) is

15. The light emitting device of claim 9 , wherein N in structure (a) or (b) is

or substituted

16. The light emitting device of claim 9 , wherein M is palladium (II).

17. The light emitting device of claim 9 , wherein the MADF emitter is one of the following:

18. The light emitting device of claim 9 , wherein the MADF emitter is a compound of General Formula A:

wherein:
M is Ir, Rh, Mn, Ni, Cu, or Ag;
each R 1 and R 2 is independently hydrogen, halogen, hydroxyl, nitro, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 1a and Y 1b is independently O, NR 3 , CR 3 R 4 , S, AsR 3 , BR 3 , PR 3 , P(O)R 3 , or SiR 3 R 4 , or a combination thereof, wherein each of R 3 and R 4 is independently hydrogen; halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, arylalkene, or R 3 and R 4 together form C═O, wherein each of R 3 and R 4 is independently optionally linked to an adjacent ring structure, thereby forming a cyclic structure;
each of Y 2a , Y 2b , Y 2c , and Y 2d is independently N or CR 5 , wherein R 5 is hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of Y 3a , Y 3b , Y 3c , Y 3d , Y 4a , Y 4b , Y 4c , and Y 4d is independently N, O, S, NR 6 , or CR 7 , wherein each of R 6 and R 7 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene; or Z(R 8 ) 2 , wherein Z is C or Si, and wherein each R 8 is independently hydrogen, halogen, hydroxyl, thiol, or substituted or unsubstituted alkyl, alkenyl, alkynyl, aryl, heteroaryl, cycloalkane, cycloalkane, heterocyclyl, amino, alkoxy, haloalkyl, arylalkane, or arylalkene;
each of m and n is independently 1 or 2; and
ea

Assignees

• Univ Arizona State

Inventors

• Li Jian

Classifications

• H01L51/5012

  Electricity · mapped topic

• H01L51/0062

  Electricity · mapped topic

• H01L51/0091

  Electricity · mapped topic

• H01L51/0069

  Electricity · mapped topic

• H01L51/0073

  Electricity · mapped topic