Light emitting device including semiconductor nanocrystals
A light emitting device includes a semiconductor nanocrystal and a charge transporting layer that includes an inorganic material. The charge transporting layer can be a hole or electron transporting layer. The inorganic material can be an inorganic semiconductor.
1. A light emitting device comprising:
a first charge transporting layer including a first inorganic material in contact with a first electrode arranged to introduce charge in the first charge transporting layer, wherein the first inorganic material is amorphous or polycrystalline;
a second electrode;
a layer including an emissive material comprising a plurality of semiconductor nanocrystals disposed between the first electrode and the second electrode, and
a doped layer proximal to the nanocrystals, wherein the doped layer includes a dopant comprising an oxygen deficiency, a halogen dopant, a mixed metal, a p-type dopant, or an n-type dopant in an amount effective to minimize non-radiative losses;
wherein the band gap of the first inorganic material is greater than the emission energy of the semiconductor nanocrystals.
2. The light emitting device of claim 1 , further comprising a second charge transporting layer in contact with the second electrode, wherein the second electrode is arranged to introduce charge in the second charge transporting layer.
3. The light emitting device of claim 1 , wherein the first inorganic material is an inorganic semiconductor.
4. The light emitting device of claim 3 , wherein the inorganic semiconductor includes a metal chalcogenide.
5. The light emitting device of claim 4 , wherein the metal chalcogenide is a mixed metal chalcogenide.
6. The light emitting device of claim 4 , wherein the metal chalcogenide includes a zinc oxide, a titanium oxide, a niobium oxide, a zinc sulfide, an indium tin oxide, or a mixture thereof.
7. The light emitting device of claim 3 , wherein the inorganic semiconductor includes a dopant.
8. The light emitting device of claim 1 , wherein the second charge transporting layer includes a second inorganic material.
9. The light emitting device of claim 8 , wherein the second inorganic material is amorphous or polycrystalline.
10. The light emitting device of claim 8 , wherein the second inorganic material is an inorganic semiconductor.
11. The light emitting device of claim 10 , wherein the inorganic semiconductor includes a metal chalcogenide.
12. The light emitting device of claim 11 , wherein the metal chalcogenide is a mixed metal chalcogenide.
13. The light emitting device of claim 11 , wherein the metal chalcogenide includes a zinc oxide, a titanium oxide, a niobium oxide, a zinc sulfide, an indium tin oxide, or a mixture thereof.
14. The light emitting device of claim 1 , wherein the first charge transporting layer is a hole transporting layer.
15. The light emitting device of claim 1 , wherein the first charge transporting layer is an electron transporting layer.
16. The light emitting device of claim 1 , wherein the plurality of semiconductor nanocrystals form a monolayer.
17. The light emitting device of claim 1 , wherein the plurality of semiconductor nanocrystals is a substantially monodisperse population of semiconductor nanocrystals.
18. The light emitting device of claim 1 , wherein the plurality of semiconductor nanocrystals is arranged in a pattern.
19. The light emitting device of claim 1 , wherein the device is transparent.
20. A light emitting device of claim 1 , wherein the semiconductor nanocrystals include a core and an overcoating of a semiconductor material.
21. A light emitting device of claim 1 wherein the first charge transporting layer consists essentially of one or more inorganic materials.
22. A display including a plurality of light emitting devices, wherein at least one light emitting device comprises:
a first charge transporting layer including a first inorganic material in contact with a first electrode arranged to introduce charge in the first charge transporting layer, wherein the first inorganic material is amorphous or polycrystalline;
a second electrode;
a layer including an emissive material comprising a plurality of semiconductor nanocrystals disposed between the first electrode and the second electrode, and
a doped layer proximal to the nanocrystals, wherein the doped layer includes a dopant comprising an oxygen deficiency, a halogen dopant, a mixed metal, a p-type dopant, or an n-type dopant in an amount effective to minimize non-radiative losses;
wherein the band gap of the first inorganic material is greater than the emission energy of the semiconductor nanocrystals.
23. The display of claim 22 , further comprising a second charge transporting layer in contact with the second electrode, wherein the second electrode is arranged to introduce charge in the second charge transporting layer.
24. The display of claim 22 , wherein the first inorganic material is an inorganic semiconductor.
25. The display of claim 24 , wherein the inorganic semiconductor includes a metal chalcogenide.
26. The display of claim 25 , wherein the metal chalcogenide is a mixed metal chalcogenide.
27. The display of claim 25 , wherein the metal chalcogenide includes a zinc oxide, a titanium oxide, a niobium oxide, a zinc sulfide, an indium tin oxide, or a mixture thereof.
28. The display of claim 22 , wherein the second charge transporting layer includes a second inorganic material.
29. The display of claim 28 , wherein the second inorganic material is amorphous or polycrystalline.
30. The display of claim 28 , wherein the second inorganic material is an inorganic semiconductor.
31. The display of claim 30 , wherein the inorganic semiconductor includes a metal chalcogenide.
32. The display of claim 31 , wherein the metal chalcogenide is a mixed metal chalcogenide.
33. The display of claim 31 , wherein the metal chalcogenide includes a zinc oxide, a titanium oxide, a niobium oxide, a zinc sulfide, an indium tin oxide, or a mixture thereof.
34. The display of claim 22 , wherein the first charge transporting layer is a hole transporting layer.
35. The display of claim 22 , wherein the first charge transporting layer is an electron transporting layer.
36. The display of claim 22 , wherein the plurality of semiconductor nanocrystals form a monolayer.
37. The display of claim 22 , wherein the plurality of semiconductor nanocrystals is a substantially monodisperse population of semiconductor nanocrystals.
38. The display of claim 22 , wherein the plurality of semiconductor nanocrystals is arranged in a pattern.
39. The display of claim 22 , wherein the device is transparent.
40. A light emitting device of claim 22 wherein the first charge transporting layer consists essentially of one or more inorganic materials.