Quantum dot light-emitting device
There is provided a quantum dot light-emitting device including: a light-emitting layer containing a quantum dot luminescent material; and a metal-based particle assembly layer being a layer consisting of a particle assembly including 30 or more metal-based particles separated from each other and disposed in two-dimensions, said metal-based particles having an average particle diameter in a range of 200 to 1600 nm, an average height in a range of 55 to 500 nm, and an aspect ratio, as defined by a ratio of said average particle diameter to said average height, in a range of 1 to 8, wherein said metal-based particles that compose said metal-based particle assembly layer are disposed such that an average distance between adjacent metal-based particles may be in a range of 1 to 150 nm. The quantum dot light-emitting device provides enhanced emission via the metal-based particle assembly layer and thus presents high luminous efficiency.
1. A quantum dot light-emitting device comprising:
a light-emitting layer containing a quantum dot luminescent material; and
a metal-based particle assembly layer being a layer consisting of a particle assembly including 30 or more metal-based particles separated from each other and disposed in two-dimensions, said metal-based particles having an average particle diameter in a range of from 200 to 1600 nm, an average height in a range of from 55 to 500 nm, and an aspect ratio, as defined by a ratio of said average particle diameter to said average height, in a range of from 1 to 8, wherein
said metal-based particles that compose said metal-based particle assembly layer are disposed such that an average distance between adjacent metal-based particles may be in a range of from 1 to 150 nm.
2. The quantum dot light-emitting device according to claim 1 , wherein said metal-based particles that compose said metal-based particle assembly layer are oblate particles with said aspect ratio of more than 1.
3. The quantum dot light-emitting device according to claim 1 , wherein said metal-based particles that compose said metal-based particle assembly layer are made of silver.
4. The quantum dot light-emitting device according to claim 1 , wherein said metal-based particles that compose said metal-based particle assembly layer are non-conductive between adjacent metal-based particles.
5. The quantum dot light-emitting device according to claim 1 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and the maximum wavelength is in a range of from 350 to 550 nm.
6. The quantum dot light-emitting device according to claim 1 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and an absorbance at the maximum wavelength is at least 1.
7. The quantum dot light-emitting device according to claim 1 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm.
8. The quantum dot light-emitting device according to claim 1 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm, and said quantum dot luminescent material contained in said light-emitting layer has a photoluminescence quantum efficiency of 1.5 times or larger than that of a reference quantum dot light-emitting device that does not have said metal-based particle assembly layer.
9. The quantum dot light-emitting device according to claim 1 , further comprising an insulating layer interposed between said light-emitting layer and said metal-based particle assembly layer.
10. The quantum dot light-emitting device according to claim 9 , wherein said insulating layer is formed so as to cover a surface of each metal-based particle that composes said metal-based particle assembly layer.
11. A quantum dot light-emitting device comprising:
a light-emitting layer containing a quantum dot luminescent material; and
a metal-based particle assembly layer being a layer consisting of a particle assembly including 30 or more metal-based particles separated from each other and disposed in two dimensions, said metal-based particles having an average particle diameter in a range of from 200 to 1600 nm, an average height in a range of from 55 to 500 nm, and an aspect ratio, as defined by a ratio of said average particle diameter to said average height, in a range of from 1 to 8, wherein
said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and the maximum wavelength shifts toward a shorter side in wavelength in a range of from 30 to 500 nm as compared with that of a reference metal-based particle assembly in which metal-based particles having a particle diameter equal to said average particle diameter and a height equal to said average height and made of the same material are disposed such that each distance between adjacent metal-based particles may be in a range of from 1 to 2 μm.
12. The quantum dot light-emitting device according to claim 11 , wherein said metal-based particles that compose said metal-based particle assembly layer are oblate particles with said aspect ratio of more than 1.
13. The quantum dot light-emitting device according to claim 11 , wherein said metal-based particles that compose said metal-based particle assembly layer are made of silver.
14. The quantum dot light-emitting device according to claim 11 , wherein said metal-based particles that compose said metal-based particle assembly layer are non-conductive between adjacent metal-based particles.
15. The quantum dot light-emitting device according to claim 11 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and the maximum wavelength is in a range of from 350 to 550 nm.
16. The quantum dot light-emitting device according to claim 11 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and an absorbance at the maximum wavelength is at least 1.
17. The quantum dot light-emitting device according to claim 11 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm.
18. The quantum dot light-emitting device according to claim 11 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm, and said quantum dot luminescent material contained in said light-emitting layer has a photoluminescence quantum efficiency of 1.5 times or larger than that of a reference quantum dot light-emitting device that does not have said metal-based particle assembly layer.
19. The quantum dot light-emitting device according to claim 11 , further comprising an insulating layer interposed between said light-emitting layer and said metal-based particle assembly layer.
20. The quantum dot light-emitting device according to claim 19 , wherein said insulating layer is formed so as to cover a surface of each metal-based particle that composes said metal-based particle assembly layer.
21. A quantum dot light-emitting device comprising:
a light-emitting layer containing a quantum dot luminescent material; and
a metal-based particle assembly layer being a layer consisting of a particle assembly including 30 or more metal-based particles separated from each other and disposed in two dimensions, said metal-based particles having an average particle diameter in a range of from 200 to 1600 nm, an average height in a range of from 55 to 500 nm, and an aspect ratio, as defined by a ratio of said average particle diameter to said average height, in a range of from 1 to 8, wherein
said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and an absorbance at the maximum wavelength is higher as compared with that of a reference metal-based particle assembly in which metal-based particles having a particle diameter equal to said average particle diameter and a height equal to said average height and made of the same material are disposed such that each distance between adjacent metal-based particles may be in a range of from 1 to 2 μm, on the premise that the numbers of the metal-based particles are the same.
22. The quantum dot light-emitting device according to claim 21 , wherein said metal-based particles that compose said metal-based particle assembly layer are oblate particles with said aspect ratio of more than 1.
23. The quantum dot light-emitting device according to claim 21 , wherein said metal-based particles that compose said metal-based particle assembly layer are made of silver.
24. The quantum dot light-emitting device according to claim 21 , wherein said metal-based particles that compose said metal-based particle assembly layer are non-conductive between adjacent metal-based particles.
25. The quantum dot light-emitting device according to claim 21 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and the maximum wavelength is in a range of from 350 to 550 nm.
26. The quantum dot light-emitting device according to claim 21 , wherein said metal-based particle assembly layer has in an absorption spectrum for a visible light region a maximum wavelength of a peak at a longest side in wavelength, and an absorbance at the maximum wavelength is at least 1.
27. The quantum dot light-emitting device according to claim 21 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm.
28. The quantum dot light-emitting device according to claim 21 , wherein a distance between a light-emitting layer side surface of said metal-based particle assembly layer and said light-emitting layer is at least 10 nm, and said quantum dot luminescent material contained in said light-emitting layer has a photoluminescence quantum efficiency of 1.5 times or larger than that of a reference quantum dot light-emitting device that does not have said metal-based particle assembly layer.
29. The quantum dot light-emitting device according to claim 21 , further comprising an insulating layer interposed between said light-emitting layer and said metal-based particle assembly layer.
30. The quantum dot light-emitting device according to claim 29 , wherein said insulating layer is formed so as to cover a surface of each metal-based particle that composes said metal-based particle assembly layer.