Phosphorescent organometallic iridium complex, light-emitting element, light-emitting device, electronic device, and lighting device
A novel phosphorescent organometallic iridium complex is provided in which a coordination position of a ligand with respect to a metal can be controlled in synthesis. A novel phosphorescent organometallic iridium complex is provided which can keep high quantum efficiency and can emit phosphorescence in the blue to green wavelength region. A phosphorescent organometallic iridium complex which includes a structure represented by General Formula (G1) and whose ligand is a 4H-1,2,4-triazole compound which has an unsubstituted phenyl group at the 3-position, a substituted or unsubstituted phenyl group at the 4-position, and a phenyl group at the 5-position. In the phenyl group at the 5-position, an alkyl group is bonded to at least one of the ortho-positions, and the other of the ortho-positions, the meta-positions, and the para-position are substituted or unsubstituted.
1. A complex comprising a structure represented by Formula (G1),
wherein:
R 1 represents an alkyl group having 1 to 6 carbon atoms; and
R 2 to R 10 independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms.
2. The complex according to claim 1 , wherein the complex is represented by Formula (G2):
3. The complex according to claim 1 , wherein the complex is represented by any one of Formulae (100), (101), (105), (112), and (121):
4. A light-emitting device comprising a complex,
wherein:
the complex is represented by Formula (G1);
R 1 represents an alkyl group having 1 to 6 carbon atoms; and
R 2 to R 10 independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms.
5. The light-emitting device according to claim 4 , wherein the complex is represented by Formula (G2):
6. The light-emitting device according to claim 4 , wherein the complex is represented by any one of Formulae (100), (101), (105), (112), and (121):
7. An electronic device comprising the light-emitting device according to claim 4 .
8. A lighting device comprising the light-emitting device according to claim 4 .
9. A light-emitting device comprising a light-emitting layer,
wherein:
the light-emitting layer comprises a complex represented by Formula (G1) and a first organic compound;
R 1 represents an alkyl group having 1 to 6 carbon atoms; and
R 2 to R 10 independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms.
10. The light-emitting device according to claim 9 , wherein the complex is represented by Formula (G2):
11. The light-emitting device according to claim 9 , wherein the complex is represented by any one of Formulae (100), (101), (105), (112), and (121):
12. The light-emitting device according to claim 9 , wherein the first organic compound is selected from an aromatic amine, a carbazole derivative, a nitrogen-containing heterocyclic compound, and a metal complex.
13. The light-emitting device according to claim 9 , further comprising a second organic compound in the light-emitting layer,
wherein:
the first organic compound is a nitrogen-containing heteroaromatic compound; and
the second organic compound is selected from a carbazole derivative, an indole derivative and an aromatic amine.
14. An electronic device comprising the light-emitting device according to claim 9 .
15. A lighting device comprising the light-emitting device according to claim 9 .
16. A light-emitting device comprising a first light-emitting layer and a second light-emitting layer over the first light-emitting layer,
wherein:
the first light-emitting layer comprises a first complex, a first compound, and a second compound;
the second light-emitting layer comprises a second complex and the first compound;
each of the first complex and the second complex is represented by Formula (G1);
R 1 represents an alkyl group having 1 to 6 carbon atoms; and
R 2 to R 10 independently represent hydrogen or an alkyl group having 1 to 6 carbon atoms.
17. The light-emitting device according to claim 16 , wherein each of the first complex and the second complex is represented by Formula (G2):
18. The light-emitting device according to claim 16 , wherein each of the first complex and the second complex is represented by any one of Formulae (100), (101), (105), (112), and (121):
19. The light-emitting device according to claim 16 ,
wherein:
the first compound is a nitrogen-containing heteroaromatic compound; and
the second compound is selected from a carbazole derivative, an indole derivative, and an aromatic amine.
20. The light-emitting device according to claim 16 , wherein the first complex is different from the second complex.
21. An electronic device comprising the light-emitting device according to claim 16 .
22. A lighting device comprising the light-emitting device according to claim 16 .
23. The light-emitting device according to claim 16 , comprising a charge generation layer between the first light-emitting layer and the second light-emitting layer.
24. The light-emitting device according to claim 9 , wherein the first organic compound is 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline.