Quantum-dot light emitting diode and quantum-dot light emitting display device including the same
The present disclosure provides a quantum dot (QD) light emitting diode including: a first electrode and a second electrode facing each other; a QD emitting material layer positioned between the first electrode and the second electrode and including a QD; a hole auxiliary layer positioned between the first electrode and the QD emitting material layer; and an electron transporting layer positioned between the QD emitting material layer and the second electrode and including an electron-property material and a hole-property material.
1. A quantum dot (QD) light emitting diode, comprising:
a first electrode and a second electrode facing each other;
a QD emitting material layer positioned between the first electrode and the second electrode and including a QD;
a hole auxiliary layer positioned between the first electrode and the QD emitting material layer; and
an electron transporting layer positioned between the QD emitting material layer and the second electrode and including an electron-property material and a hole-property material,
wherein:
the electron-property material is a zinc oxide material,
the hole-property material is at least one of the following materials:
and
n is an integer of 1 to 10000.
2. The QD light emitting diode according to claim 1 , wherein a HOMO level difference between the electron-property material and the hole-property material is about 0.9 to 1.6 eV, and a LUMO level difference between the electron-property material and the hole-property material is about 1.3 to 2 eV.
3. The QD light emitting diode according to claim 1 , wherein a difference between a HOMO level of the hole-property material and a LUMO level of the electron-property material is about 1.5 to 2.5 eV.
4. The QD light emitting diode according to claim 1 , wherein the electron-property material has a weight ratio greater than the hole-property material.
5. The QD light emitting diode according to claim 4 , wherein the weight ratio of the electron-property material to the hole-property material is about 240:1 to about 6:1.
6. The QD light emitting diode according to claim 1 , wherein a light having a first wavelength range is emitted from the electron transporting layer, and the first wavelength range overlaps at least a portion of a second wavelength range as an absorption wavelength range of the QD.
7. A QD light emitting display device, comprising:
a substrate including a red pixel region, a green pixel region and a blue pixel region;
a QD light emitting diode positioned on or over the substrate, the QD light emitting diode including:
a first electrode and a second electrode facing each other;
a QD emitting material layer positioned between the first electrode and the second electrode and including a QD;
a hole auxiliary layer positioned between the first electrode and the QD emitting material layer; and
an electron transporting layer positioned between the QD emitting material layer and the second electrode; and
a thin film transistor positioned between the substrate and the QD light emitting diode and connected to the QD light emitting diode,
wherein:
the electron transporting layer in the red pixel region includes an electron-property material and a hole-property material, and
the electron transporting layer in the blue pixel region includes the electron-property material and excludes the hole-property material.
8. The QD light emitting display device according to claim 7 , wherein the electron-property material in the blue pixel region is same as or different from the electron-property material in the red pixel region.
9. The QD light emitting display device according to claim 7 , wherein the electron transporting layer in the green pixel region includes the electron-property material and excludes the hole-property material.
10. The QD light emitting display device according to claim 9 , wherein the electron-property material in the green pixel region is same as or different from the electron-property material in the red pixel region.
11. The QD light emitting display device according to claim 7 , wherein the electron transporting layer in the green pixel region includes the electron-property material and the hole-property material.
12. The QD light emitting display device according to claim 11 , wherein the hole-property material in the green pixel region is same as or different from the hole-property material in the red pixel region.
13. The QD light emitting display device according to claim 7 , wherein a HOMO level difference between the electron-property material and the hole-property material is about 0.9 to 1.6 eV, and a LUMO level difference between the electron-property material and the hole-property material is about 1.3 to 2 eV.
14. The QD light emitting display device according to claim 7 , wherein a difference between a HOMO level of the hole-property material and a LUMO level of the electron-property material is about 1.5 to 2.5 eV.
15. The QD light emitting display device according to claim 7 , wherein in the electron transporting layer in the red pixel region, the electron-property material has a weight ratio greater than the hole-property material.
16. The QD light emitting display device according to claim 15 , wherein the weight ratio of the electron-property material to the hole-property material is about 240:1 to about 6:1.
17. The QD light emitting display device according to claim 7 , wherein:
the electron-property material is a zinc oxide material,
the hole-property material is at least one of the following materials:
and
n is an integer of 1 to 10000.
18. The QD light emitting display device according to claim 7 , wherein a light having a first wavelength range is emitted from the electron transporting layer in the red pixel region, and the first wavelength range overlaps at least a portion of a second wavelength range as an absorption wavelength range of the QD in the red pixel region.
19. A quantum dot (QD) light emitting diode, comprising:
a first electrode and a second electrode facing each other;
a QD emitting material layer positioned between the first electrode and the second electrode and including a QD;
a hole auxiliary layer positioned between the first electrode and the QD emitting material layer; and
an electron transporting layer positioned between the QD emitting material layer and the second electrode and including an electron-property material and a hole-property material,
wherein an electron mobility of the electron-property material is greater than a hole mobility of the electron-property material, and a hole mobility of the hole-property material is greater than an electron mobility of the hole-property material.
20. The QD light emitting diode according to claim 19 , wherein the electron-property material and the hole-property material are mixed in the electron transporting layer.