Organic light emitting diode containing a novel Ir complex as a phosphorescent emitter
View Patent ↗A phosphorescent Ir complex having the following structures (I) or (II) is used as an emitter in an organic light emitting diode (OLED): wherein X is an arbitrary monoanionic bidentate ligand; Z is an arbitrary moiety constituting a nitrogen-containing heterocyclic group; R 1 is a substituent on the nitrogen-containing heterocyclic group; m is 0 or a positive integer; R 2 and R 3 independently are H, halogen, C1-C6 alkyl, a halogen-substituted C1-C6 alkyl, C1-C6 alkoxy, phenyl C1-C6 alkyl, amino, aryl, heterocyclic aryl substituent.
1. An organic light emitting diode (OLED) comprising: an anode on a substrate, an electroluminescent medium on said anode, and a cathode on said electroluminescent medium, characterized in that said electroluminescent medium comprises a light emitting layer comprising a phosphorescent Ir complex having the following structures (I) or (II):
wherein X is an arbitrary monoanionic bidentate ligand;
Z is an arbitrary atomic moiety capable of forming a nitrogen-containing heterocyclic group;
R 1 is selected from the group consisting of H, halogen, C1-C6 alkyl, halogen-substituted C1-C6 alkyl, C1-C6 alkoxy, phenyl C1-C6 alkyl, amino, and aryl;
m is 0 or any positive integer determined by the ring size of said nitrogen-containing heterocyclic group;
R 2 is selected from the group consisting of H, halogen, C1-C6alkyl, halogen-substituted C1-C6alkyl, C1-C6alkoxy, phenyl C1-C6alkyl, amino, aryl, and heterocyclic aryl; and
R 3 is aryl or heterocyclic aryl;
and provided that said nitrogen-containing heterocyclic group containing said Z moiety is not pyridine, quinoline or isoquinoline.
2. The OLED as claimed in claim 1 , wherein said aryl is phenyl, naphthyl, diphenyl, anthryl, pyrenyl, or phenanthryl; said heterocyclic aryl is benzofuran or thiophene.
3. The OLED as claimed in claim 1 , wherein said nitrogen-containing heterocyclic group is pyrazine, pyrimidine, pyrrole, pyrazole, imidazole, indole, thiazole, isothiazole, oxazole, isoxazole, benzothiazole, benzoxazole, or phenanthroline.
4. The OLED as claimed in claim 3 , wherein said nitrogen-containing heterocyclic group is benzothiazole.
5. The OLED as claimed in claim 1 , wherein R 2 is H or methyl; and R 3 is aryl group.
6. The OLED as claimed in claim 5 wherein R 3 is phenyl or naphthyl.
7. The OLED as claimed in claim 1 , wherein said phosphorescent Ir complex has the structure (I), and X is acetylacetonate, aminoacid, salicylaldehyde, or iminoacetonate.
8. The OLED as claimed in claim 7 , wherein X is acetylacetonate.
9. The OLED as claimed in claim 7 , wherein X is aminoacid or salicylaldehyde.
10. The OLED as claimed in claim 1 , wherein said light emitting layer will emit yellow to red light, when a voltage is applied on said anode and said cathode.
11. The OLED as claimed in claim 1 , wherein said light emitting layer further comprises a host compound, and said Ir complex is doped into said host compound.
12. The OLED as claimed in claim 11 , wherein said host compound is a compound having a hole transporting capability.
13. The OLED as claimed in claim 12 , wherein said compound having a hole transporting capability is:
14. The OLED as claimed in claim 12 , wherein said compound having a hole transporting capability is:
15. The OLED as claimed in claim 11 , wherein said host compound is a compound having an electron transporting capability.
16. The OLED as claimed in claim 15 , wherein said compound having an electron transporting capability is:
17. The OLED as claimed in claim 1 , wherein said electroluminescent medium further comprises a hole transporting layer between said anode and said light emitting layer.
18. The OLED as claimed in claim 17 , wherein said hole transporting layer comprises a compound of the following structure:
19. The OLED as claimed in claim 17 , wherein said electroluminescent medium further comprises a hole injection modification layer between said anode and said hole transporting layer.
20. The OLED as claimed in claim 19 , wherein said hole injection modification layer comprises a compound of the following structure:
21. The OLED as claimed in claim 1 , wherein said electroluminescent medium further comprises a hole-blocking layer between said cathode and said light emitting layer, and said hole-blocking layer contacts said light emitting layer.
22. The OLED as claimed in claim 21 , wherein said hole-blocking layer comprises a compound of the following structure:
wherein Ph is phenyl, and Me is methyl.
23. The OLED as claimed in claim 21 , wherein said hole-blocking layer comprises a compound of the following structure:
24. The OLED as claimed in claim 21 , wherein said hole-blocking layer comprises a compound of the following structure:
wherein Me is methyl.
25. The OLED as claimed in claim 21 , wherein said electroluminescent medium further comprises an electron transporting layer between said hole-blocking layer and said cathode.
26. The OLED as claimed in claim 25 , wherein said electron transporting layer comprises a compound of the following structure:
27. The OLED as claimed in claim 1 , wherein said phosphorescent Ir complex is