CORE-SHELL NANOWIRE, METHOD FOR SYNTHESIZING THE CORE-SHELL NANOWIRE, AND TRANSPARENT ELECTRODE AND ORGANIC LIGHT EMITTING DIODE INCLUDING THE CORE-SHELL NANOWIRE

20180026224 ยท 2018-01-25

Assignee

Inventors

Cpc classification

International classification

Abstract

A nanowire according to an embodiment of the invention comprises a nanowire core and a metal-compound coated on the nanowire core, wherein the nanowire core comprises at least two bent portions, and wherein an angle () between an n-th wire portion and an (n+1)-th wire portion connected to the n-th wire portion through an n-th bent portion satisfies an inequation of 0<<180.

Claims

1. A core-shell nanowire, comprising: a nanowire core; and a metal-compound shell formed on the nanowire core.

2. The core-shell nanowire according to claim 1, wherein the metal-compound shell comprises a transparent conductive metal compound.

3. The core-shell nanowire according to claim 1, wherein the metal-compound shell has a plurality of protruded structures when viewed in a cross-sectional view perpendicular to a length direction of the core-shell nanowire, and an area or a width of the protruded structure gradually decreases as the distance from the nanowire core increases.

4. The core-shell nanowire according to claim 1, wherein the metal-compound shell has a shape of a plurality of polygons when viewed in a cross-sectional view perpendicular to a length direction of the core-shell nanowire.

5. The core-shell nanowire according to claim 4, wherein the polygon of the metal-compound shell is a triangular shape or a trapezoid shape.

6. The core-shell nanowire according to claim 1, wherein the metal-compound shell has a stripe pattern having a plurality of portions extending a longitudinal direction of the nanowire core.

7. The core-shell nanowire according to claim 3, wherein the number of the plurality of protruded portions viewed in the cross-sectional is three to six.

8. The core-shell nanowire according to claim 4, wherein the number of the plurality of polygons viewed in the cross-sectional is three to six.

9. The core-shell nanowire according to claim 6, wherein the number of the plurality of portions constituting the stripe pattern is three to six.

10. The core-shell nanowire according to claim 4, wherein, when a side of one of the polygons adjacent to the nanowire core is a bottom side of one of the polygons, the bottom side of one of the polygons has a length (d) of 40 nm to 200 nm and a height (c) of 10 nm to 200 nm.

11. The core-shell nanowire according to claim 1, wherein the core-shell nanowire has a length (a) of in a range of 10 m300 m.

12. The core-shell nanowire according to claim 4, wherein a ratio (c/a) of the height (c) of one of the polygon to a length (a) of the core-shell nanowire is in a range of 0.00006 to 0.02.

13. The core-shell nanowire according to claim 11, wherein a ratio (f/a) of a longest diameter (f) of one of the polygons, when viewed in the cross-sectional view perpendicular to the longitudinal direction of the core-shell nanowire, to a length (a) of the core-shell nanowire is in a range of 0.0001 to 0.06.

14. The core-shell nanowire according to claim 11, wherein, when the core-shell nanowire is coated on a transparent substrate to have a sheet resistance of 1100(/), a haze is in a range of 5% or more at a wavelength of 550 nm.

15. The core-shell nanowire according to claim 14, wherein the haze is in a range of 20% or more at the wavelength of 550 nm.

16. The core-shell nanowire according to claim 1, wherein, when the core-shell nanowire is coated on a transparent substrate to have a sheet resistance of 1100(/), a light transmittance is in a range of 60 to 98% at a wavelength of 550 nm.

17. The core-shell nanowire according to claim 1, wherein the metal-compound shell includes at least one selected from a group consisting of ZnO, SiO2, SnO2, TiO2, AlN, GaN, BN, InN, ZnS, CdS, ZnSe, ZnTe, CdSe, and carbon.

18. A nanowire, comprising: a nanowire core; and a metal-compound coated on the nanowire core.

19. The core-shell nanowire according to one of claims 1, wherein the nanowire core comprises at least two wire portions, and wherein an angle () between an n-th wire portion and an (n+1)-th wire portion connected to the n-th wire portion through an n-th bent portion satisfies the following Inequation 1.[Inequation 1]0<<180.

20. The core-shell nanowire according to claim 19, wherein the angle () between the n-th wire portion and the (n+1)-th wire portion satisfies an inequation of 130170.

21. The core-shell nanowire according to claim 20, further comprising: an (n+2)-th wire portion connected to the (n+1)-th wire portion through an (n+1)-th bent portion, wherein, when a plane comprising the n-th wire portion and the (n+1)-th wire portion is an A plane and a plane comprising the (n+1)-th wire portion and the (n+2)-th wire portion is a B plane, an angle () of the B plane with respect to the A plane is in a range of 10 to 10.

22. The core-shell nanowire according to one of claims 1, wherein the nanowire core comprises at least two wire parts, the nanowire core comprises an n-th wire part and an (n+1)-th wire part connected to the n-th wire part, and a diameter of the n-th wire part is different from a diameter of the (n+1)-th wire part.

23. The core-shell nanowire according to one of claims 1, wherein the nanowire core comprises a first wire part having a first diameter, and a second wire part having a second diameter and extended from the first wire part, and the first diameter is different from the second diameter.

24. The core-shell nanowire according to claim 23, wherein the second wire part is formed at one end or both ends of the first wire part.

25. The core-shell nanowire according to claim 23, wherein the first diameter is in a range of 50 to 100 nm, and the second diameter is in a range of 150 to 1100 nm.

26. A transparent electrode, comprising: a conductor layer comprising a core-shell nanowire; and a transparent electrode layer formed on the conductor layer,wherein the core nanowire comprises a nanowire core, and a metal-compound shell formed on the nanowire core.

27. The transparent electrode according to claim 26, wherein the metal-compound shell has a plurality of protruded structures when viewed in a cross-sectional view perpendicular to a length direction of the transparent electrode, and an area or a width of the protruded structure gradually decreases as the distance from the nanowire core increases.

28. The transparent electrode according to claim 26, wherein the nanowire core comprises at least one wire portion, and wherein an angle () between an n-th wire portion and an (n+1)-th wire portion connected to the n-th wire portion through an n-th bent portion satisfies an inequation of 130170.

29. The transparent electrode according to claim 26, wherein the nanowire core comprises at least one wire part, the nanowire core comprises an n-th wire part and an (n+1)-th wire part connected to the n-th wire part, and a first diameter of the n-th wire part is different from a first diameter of the (n+1)-th wire part.

30. An organic light emitting diode, comprising: a transparent substrate; a first electrode provided on the transparent substrate; a second electrode facing the first electrode; and an organic light emitting layer provided between the first electrode and the second electrode,wherein the first electrode comprises a transparent electrode according to one of claims 26.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0235] FIG. 1 illustrates a metal nanowire including two wire portions having a bent portion, according to an embodiment of the invention.

[0236] FIG. 2 illustrates a metal nanowire including a plurality of wire portions having at least one bent portion, according to another embodiment of the invention.

[0237] FIG. 3 illustrates a three-dimensional structure of a metal nanowire including a plurality of wire portions having at least one bent portion, according to yet another embodiment of the invention.

[0238] FIG. 4 illustrates a metal nanowire including a plurality of wire parts having different diameters, wherein the plurality of wire parts including one second wire part, according to yet still another embodiment of the invention.

[0239] FIG. 5 illustrates a metal nanowire including a plurality of wire parts having different diameters according to another embodiment of the invention, wherein (a) illustrates the metal nanowire including a second wire part formed at one end and (b) illustrates the metal nanowire including second wire parts formed at both ends.

[0240] FIG. 6 illustrates wire portions of a metal nanowire having at least one bent portion according to yet still another embodiment of the invention.

[0241] FIG. 7 illustrates the metal nanowire having at least one bent portion according to yet still another embodiment of the invention.

[0242] FIG. 8 illustrates wire parts of a metal nanowire having different diameters according to yet still another embodiment of the invention.

[0243] FIG. 9 illustrates the metal nanowire having different diameters according to yet still another embodiment of the invention.

[0244] FIG. 10 to FIG. 13 schematically illustrate core-shell nanowires according to embodiments of the invention.

[0245] FIG. 14 a schematically view of a roll-to-roll continuation process for forming a core-shell nanowire according to an embodiment of the invention.

[0246] FIG. 15 is a photograph of a surface of silver nanowires according to an embodiment of the invention, taken using a scanning electron microscopy.

[0247] FIG. 16 is a photograph of silver nanowires having a plurality of wire parts having different diameters according to an embodiment of the invention, taken using a scanning electron microscopy.

[0248] FIG. 17 and FIG. 18 are photographs of silver nanowires including a plurality of wire portions having at least one bent portion according to an embodiment of the invention, taken using a transmission electron microscopy.

[0249] FIG. 19 is a photograph of silver nanowires not including a plurality of wire portions and not having at least one bent portion as a comparative example, taken using a transmission electron microscopy.

[0250] FIG. 20 is graphs of transmittances, wherein (a) of FIG. 20 is a graph of a transmittance of a transparent substrate including silver nanowires according to each of Embodiments 11 to 15, and (b) of FIG. 20 is a graph of a transmittance of a transparent substrate including silver nanowires according to each of Embodiments 16 to 20.

[0251] FIG. 21 is graphs of hazes, wherein (a) of FIG. 21 is a graph of a haze of a transparent substrate including silver nanowires according to each of Embodiments 11 to 15, and (b) of FIG. 21 is a graph of a haze of a transparent substrate including silver nanowires according to each of Embodiments 16 to 20.

[0252] FIG. 22 and FIG. 23 are scanning electron microscopy photographs of core-shell nanowires according to Embodiments 23 to 27, wherein (a) of FIG. 22 corresponds to Embodiment 23, (b) of FIG. 22 corresponds to Embodiment 24, (c) of FIG. 23 corresponds to Embodiment 25, (a) of FIG. 23 corresponds to Embodiment 26, and (b) of FIG. 23 corresponds to Embodiment 27.

[0253] FIG. 24 is a photograph for illustrating that a zinc oxide is selectively coated on a nanowire formed on a core-shell nanowire substrate, according to Embodiment 25.

[0254] FIG. 25 is a graph of sheet resistances of each of Embodiments of Comparative Examples.

[0255] FIG. 26 is X-ray diffraction peaks of the core-shell nanowires according to Embodiments, wherein (a) of FIG. 26 corresponds to Embodiment 23, (b) of FIG. 26 corresponds to Embodiment 24, and (c) of FIG. 26 corresponds to Embodiment 27.

[0256] FIG. 27 to FIG. 29 are graphs of light transmittances of Embodiment 23 to Embodiment 27, wherein (a) of FIG. 27 corresponds to Embodiment 23, (b) of FIG. 27 corresponds to Embodiment 24, (a) of FIG. 28 corresponds to Embodiment 25, (b) of FIG. 28 corresponds to Embodiment 26, and 29 corresponds to Embodiment 27.

[0257] FIG. 30 to FIG. 32 are graphs of hazes of Embodiment 23 to Embodiment 27, wherein (a) of FIG. 30 corresponds to Embodiment 23, (b) of FIG. 30 corresponds to Embodiment 24, (a) of FIG. 31 corresponds to Embodiment 25, (b) of FIG. 31 corresponds to Embodiment 26, and FIG. 32 corresponds to Embodiment 27.

[0258] FIG. 33 is a graph of a photoluminescence (PL) according to each of Embodiments 23 to 25, wherein (a) of FIG. 33 corresponds to Embodiment 23, (b) of FIG. 33 corresponds to Embodiment 24, (c) of FIG. 33 corresponds to Embodiment 25.

[0259] FIG. 34 is a graph of a sheet resistance with respect to time, according to each of Embodiment 23 to Embodiment 27.

[0260] FIG. 35 and FIG. 36 are scanning electron microscopy photographs of core-shell nanowires according to Embodiments 28 to 32, wherein (a) of FIG. 35 corresponds to Embodiment 28, (b) of FIG. 35 corresponds to Embodiment 29, (c) of FIG. 35 corresponds to Embodiment 30, (a) of FIG. 36 corresponds to Embodiment 31, and (b) of FIG. 36 corresponds to Embodiment 32.

[0261] FIG. 37 is a photograph for illustrating that a zinc oxide is selectively coated on a nanowire formed on a core-shell nanowire substrate.

[0262] FIG. 38 is a graph of sheet resistances of each of Embodiments of Comparative Examples.

[0263] FIG. 39 is X-ray diffraction peaks of the core-shell nanowires according to Embodiments, wherein (a) of FIG. 39 corresponds to Embodiment 28, (b) of FIG. 39 corresponds to Embodiment 29, and (c) of FIG. 39 corresponds to Embodiment 32.

[0264] FIG. 40 to FIG. 42 are graphs of hazes of Embodiment 28 to Embodiment 32, wherein (a) of FIG. 40 corresponds to Embodiment 28, (b) of FIG. 40 corresponds to Embodiment 29, (a) of FIG. 41 corresponds to Embodiment 30, (b) of FIG. 41 corresponds to Embodiment 31, and FIG. 42 corresponds to Embodiment 32.

[0265] FIG. 43 to FIG. 45 are graphs of light transmittances of Embodiment 28 to Embodiment 32, wherein (a) of FIG. 43 corresponds to Embodiment 28, (b) of FIG. 43 corresponds to Embodiment 29, (a) of FIG. 44 corresponds to Embodiment 30, (b) of FIG. 44 corresponds to Embodiment 31, and FIG. 45 corresponds to Embodiment 32.

[0266] FIG. 46 is a graph of a photoluminescence (PL) according to Embodiments 28, 29, and 32, wherein (a) of FIG. 46 corresponds to Embodiment 28, (b) of FIG. 46 corresponds to Embodiment 29, (c) of FIG. 46 corresponds to Embodiment 32.

[0267] FIG. 47 is a graph of a sheet resistance with respect to time, according to each of Embodiment 28 to Embodiment 32.