Electroluminescent device, and display device comprising thereof
An electroluminescent device comprising a first electrode; a hole transport layer disposed on the first electrode; an emission layer disposed on the hole transport layer and comprising a plurality of light emitting particles; an electron transport layer disposed on the emission layer and comprising a metal oxide particle-organic polymer composite comprising a plurality of metal oxide particles and an organic polymer; and a second electrode disposed on the electron transport layer, wherein the organic polymer is present in the metal oxide particle-organic polymer composition in an amount of about 7 weight percent to about 30 weight percent based on a total weight of the electron transport layer.
1. An electroluminescent device comprising
a first electrode;
a hole transport layer disposed on the first electrode;
an emission layer disposed on the hole transport layer and comprising a plurality of light emitting particles;
an electron transport layer disposed on the emission layer and comprising a metal oxide particle-organic polymer composite comprising a plurality of metal oxide particles and an organic polymer; and
a second electrode disposed on the electron transport layer,
wherein the organic polymer is present in the metal oxide particle-organic polymer composite in an amount of about 10 weight percent to about 25 weight percent based on a total weight of the electron transport layer.
2. The electroluminescent device of claim 1 , wherein the plurality of metal oxide particles are dispersed in the organic polymer.
3. The electroluminescent device of claim 1 , wherein the organic polymer is adsorbed on at least a portion of the plurality of metal oxide particles.
4. The electroluminescent device of claim 1 , wherein the organic polymer comprises at least one of an amino-containing polymer, compound, a hydroxy-containing polymer, a (meth)acryl-containing polymer, a derivative thereof, or a combination thereof.
5. The electroluminescent device of claim 1 , wherein the organic polymer has a weight average molecular weight of about 1,000 grams per mole to about 30,000 grams per mole.
6. The electroluminescent device of claim 1 , wherein the plurality of metal oxide particle comprise at least one of ZnO, TiO 2 , ZrO 2 , SnO 2 , WO 3 , Ta 2 O 3 , or a combination thereof.
7. The electroluminescent device of claim 1 , wherein an average particle diameter of a metal oxide particle of the plurality of metal oxide particles is about 0.1 nanometers to about 10 nanometers.
8. The electroluminescent device of claim 1 , wherein a lowest unoccupied molecular orbital energy level of the electron transport layer ranges from about −4.20 electron volts to about −3.5 electron volts.
9. The electroluminescent device of claim 1 , wherein a highest unoccupied molecular orbital energy level of the electron transport layer ranges from about −8.0 electron volts to about −7.0 electron volts.
10. The electroluminescent device of claim 1 , wherein a bandgap energy of the electron transport layer ranges from about 2.5 electron volts to about 3.8 electron volts.
11. The electroluminescent device of claim 1 , wherein a thickness of the electron transport layer ranges from about 5 nanometers to about 100 nanometers.
12. The electroluminescent device of claim 1 , wherein the plurality of light emitting particles comprises a plurality of quantum dots.
13. The electroluminescent device of claim 1 , wherein each light emitting particle of the plurality of light emitting particles comprises a Group II-VI compound that does not comprise Cd, a Group III-V compound, a Group IV-VI compound, a Group IV element or compound, a Group I-III-VI compound, a Group I-II-IV-VI compound that does not comprise Cd, or a combination thereof.
14. The electroluminescent device of claim 1 , wherein the light emitting particle has a core-shell structure.
15. A display device comprising the electroluminescent device of claim 1 .
16. A method of manufacturing a display device, comprising:
providing a first electrode;
disposing a hole transport layer on the first electrode;
disposing an emission layer on the hole transport layer, wherein the emission layer comprises a plurality of light emitting particles;
disposing an electron transport layer on the emission layer, wherein the electron transport layer comprises a metal oxide particle-organic polymer composite comprising a plurality of metal oxide particles and an organic polymer; and
disposing a second electrode on the electron transport layer,
wherein the organic polymer is included in metal oxide particle-organic polymer composite in an amount of about 10 weight percent to about 25 weight percent based on a total weight of the electron transport layer.
17. The method of claim 16 , wherein the disposing of the electron transport layer comprises
combining the plurality of metal oxide particles and the organic polymer in a polar solvent to form a metal oxide particle-organic polymer composition;
coating the metal oxide particle-organic polymer composition on the emission layer; and
forming the metal oxide particle-organic polymer composite.
18. The method of claim 17 , wherein the forming comprises heating the metal oxide particle-organic polymer composition to provide the metal oxide particle-organic polymer composite.
19. The method of claim 17 , further comprising adsorbing the organic polymer on at least a portion of the plurality of metal oxide particles.
20. The method of claim 17 , wherein the polar solvent comprises methanol, ethanol, isopropanol, butanol, or a combination thereof.