ORGANIC LIGHT-EMITTING DIODES WITH FLUORESCENT AND PHOSPHORESCENT EMITTERS

• US 20170271611A1
• Filed: 08/21/2015
• Published: 09/21/2017
• Est. Priority Date: 08/22/2014
• Status: Active Grant

• Current Assignee: Arizona Board of Regents (University of Arizona)
• Original Assignee: Jian Li, Arizona Board of Regents (University of Arizona)
• Inventors: LI, Jian, FLEETHAM, Tyler
• Granted Patent: US 11,329,244 B2
• Time in Patent Office: Days
• CPC Class Codes: C09K 11/06 containing organic luminescent materials
• CPC Class Codes: C09K 2211/1011 Condensed systems
• CPC Class Codes: C09K 2211/1029 containing one nitrogen atom as the heteroatom
• CPC Class Codes: C09K 2211/185 of the platinum group, i.e. Os, Ir, Pt, Ru, Rh or Pd
• CPC Class Codes: H10K 2101/10 Triplet emission
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/121 for assisting energy transfer, e.g. sensitization
• CPC Class Codes: H10K 50/156 comprising a multilayered structure
• CPC Class Codes: H10K 50/166 comprising a multilayered structure
• CPC Class Codes: H10K 50/17 Carrier injection layers
• CPC Class Codes: H10K 85/631 Amine compounds having at least two aryl rest on at least one amine-nitrogen atom, e.g. triphenylamine
• CPC Class Codes: H10K 85/6572 comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole

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 phosphorescent emitter, a fluorescent emitter, and a host, and the phosphorescent emitter harvests electrogenerated excitons and transfers energy to the fluorescent emitter.

Claims

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 phosphorescent emitter, a fluorescent emitter, and a host, wherein the phosphorescent 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 phosphorescent 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 phosphorescent 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 phosphorescent emitter comprises a luminophore comprising a six-membered chelation ring.

9. The light emitting device of claim 8, wherein the phosphorescent emitter comprises a compound of General Formula I:

10. The light emitting device of claim 9, wherein:

M is Pt or Pd;

m is 2;

n is 2;

at least one of Y^1a and Y^1c is independently NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴;

Y^2b and Y^2c are C; and

Y^3b and Y^4b are N.

11. The light emitting device of claim 9, wherein:

M is Ir or Rh;

m is 2;

n is 2;

Y^1a is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴;

Y^2b is C; and

Y^3b Y^2c and Y^4b are N.

12. The light emitting device of claim 9, wherein:

M is Au;

m is 2;

n is 2;

Y^1b is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴;

Y^2b, Y^2c and Y^4b are C; and

Y^3b is N.

13. The light emitting device of claim 9, wherein each of R³ and R⁴ is independently linked to an adjacent ring structure.

14. The light emitting device of claim 9, wherein:

M is Pt or Pd;

at least one of Y^1b and Y^1c is independently NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴, wherein R³ is covalently linked to at least one of Y^2a, Y^2d, Y^3d, and Y^4d, thereby forming a cyclic structure; and

at least of one of Y^2a Y^2d, Y^3d and Y^4d is C.

15. The light emitting device of claim 9, wherein:

M is Ir or Rh;

Y^1b is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴, wherein R³ is covalently linked to at least one of Y^2a and Y^3d, thereby forming a cyclic structure; and

at least of one of Y^2a and Y^3d is C.

16. The light emitting device of claim 9, wherein:

M is Au;

at least of one of Y^2a and Y^3d is C; and

Y^1b is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴, wherein R³ is covalently linked to at least one of Y^2a and Y^3d, thereby forming a cyclic structure.

17. The light emitting device of claim 8, wherein the phosphorescent emitter comprises a compound of General Formula II:

18. The light emitting device of claim 17, wherein:

M is Ir or Rh;

m is 2;

Y^2b and Y^2c are C;

Y^3b and Y^4b are N; and

at least one of Y^1b and Y^1c is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴.

19. The light emitting device of claim 17, wherein each of R³ and R⁴ is independently linked to an adjacent ring structure.

20. The light emitting device of claim 17, wherein:

M is Ir or Rh;

at least of one of Y^2a, Y^2d, Y^3d and Y^4d is C; and

at least one of Y^1b and Y^1c is NR³, CR³R⁴, S, AsR³, BR³, PR³, P(O)R³, or SiR³R⁴, wherein R³ is covalently linked to at least one of Y^2a, Y^2d, Y^3d and Y^4d, thereby forming a cyclic structure.

21. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula III:

22. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula IV:

23. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula V:

24. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula VI:

25. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formulas VII and VIII:

26. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula IX:

27. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula X:

28. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula XI:

29. The light emitting device of claim 8, wherein the phosphorescent emitter is a compound of General Formula XII:

30. The light emitting device of claim 1, wherein the fluorescent emitter comprises one of the following compounds:

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