Organic electronic device for lighting
There is provided an organic electronic device including an anode, a hole transport layer, an emissive layer, an electron transport layer, and a cathode. The emissive layer includes at least one first electroluminescent material and the electron transport layer includes at least one electron transport material and at least one second electroluminescent material. The second electroluminescent material has a concentration that is greater adjacent the emissive layer. The device has white light emission.
1. An organic electronic device comprising in order: an anode, a hole transport layer, an emissive layer, an electron transport layer, and a cathode, wherein the emissive layer comprises at least one first electroluminescent material, the electron transport layer is a vapor-deposited layer comprising at least one electron transport material and at least one second electroluminescent material such that the second electroluminescent material has a concentration that is greater adjacent, and in direct contact with, the emissive layer, and wherein the device has white light emission.
2. The device of claim 1 , wherein the emissive layer further comprises a host material.
3. The device of claim 1 , wherein the emissive layer further comprises a third electroluminescent material.
4. The device of claim 3 , wherein the first electroluminescent material is a red electroluminescent material, the second electroluminescent material is a blue electroluminescent material, and the third electroluminescent material is a green electroluminescent material.
5. The device of claim 1 consisting essentially of, in order, an anode, a hole injection layer, a hole transport layer, an emissive layer, an electron transport layer, an electron injection layer, and a cathode.
6. The device of claim 1 , wherein the electron transport layer has a thickness in the range of 10-200 nm.
7. The device of claim 1 , wherein the electron transport layer has a region of undoped electron transport material adjacent the electron injection layer.
8. The device of claim 7 , wherein the region of undoped electron transport material has a thickness in the range of 5-15 nm.
9. The device of claim 3 , wherein the first and third electroluminescent materials are iridium complexes having organic ligands.
10. The device of claim 1 , wherein the second electroluminescent material is an iridium complex having organic ligands.
11. The device of claim 1 , wherein the second electroluminescent material is present in an amount of 1% to 49% by weight, based on the total weight of the electron transport layer.
12. The device of claim 1 , wherein the electron transport material is a carbazole-containing material.
13. The device of claim 1 , wherein the photoluminescence quantum yield of the electron transport layer is greater than 20%.
14. The device of claim 13 , wherein the photoluminescence quantum yield of the electron transport layer is greater than 50%.
15. The device of claim 1 , wherein the solution photoluminescence quantum yield of the at least one second electroluminescent material is greater than 20%.
16. The device of claim 15 , wherein the solution photoluminescence quantum yield is greater than 50%.