Electrical conductors, production methods thereof, and electronic devices including the same

• US 10,546,663 B2
• Filed: 10/18/2016
• Issued: 01/28/2020
• Est. Priority Date: 10/19/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hwang, Sungwoo, Kim, Se Yun, Roh, Jong Wook, Lee, Woojin, Lee, Jongmin, Jung, Doh Won, Kwak, Chan
• Primary Examiner(s): Huang, Cheng Yuan
• Application Number:
  US15/296,261
• Publication Number:
  US 20170110213A1
• Time in Patent Office: 1,197 Days
• CPC Class Codes: B32B 2264/201 Flat or platelet-shaped particles, e.g. flakes
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: H01B 1/08 oxides

Abstract

An electrical conductor includes: a first conductive layer including a plurality of ruthenium oxide nanosheets, wherein at least one ruthenium oxide nanosheet of the plurality of ruthenium oxide nanosheets includes a halogen, a chalcogen, a Group 15 element, or a combination thereof on a surface of the ruthenium oxide nanosheet.

Claims

1. An electrical conductor comprising:

a first conductive layer comprising a plurality of ruthenium oxide nanosheets, wherein at least one ruthenium oxide nanosheet of the plurality of ruthenium oxide nanosheets are surface-doped with any of a halogen, a chalcogen, a Group 15 element, and a combination thereof,

wherein the plurality of ruthenium oxide nanosheets have an average lateral size of greater than or equal to about 0.1 micrometers and less than or equal to about 100 micrometers, and a thickness of less than or equal to about 3 nanometers.

2. The electrical conductor of claim 1, wherein the halogen comprises F, Cl, Br, I, or a combination thereof, the chalcogen comprises S, Se, Te, or a combination thereof, and the Group 15 element comprises N, P, As, or a combination thereof.

3. The electrical conductor of claim 1, wherein the halogen, the chalcogen, or the Group 15 element is present as an ionic species, a surface-bound reactive group, an oxyhalide, an oxy chalcogenide, or a combination thereof.

4. The electrical conductor of claim 1, wherein the electrical conductor further comprises a second conductive layer that is disposed on a first surface of the first conductive layer, and

wherein the second conductive layer comprises a plurality of conductive metal nanowires.

5. The electrical conductor of claim 4, wherein the plurality of conductive metal nanowires comprises silver, copper, gold, aluminum, cobalt, palladium, or a combination thereof.

6. The electrical conductor of claim 4, wherein the plurality of conductive metal nanowires have an average diameter of less than or equal to about 50 nanometers and an average length of greater than or equal to about 1 micrometer.

7. The electrical conductor of claim 4, wherein at least one of the first conductive layer and the second conductive layer further comprises a binder.

8. The electrical conductor of claim 4, wherein the electrical conductor further comprises an overcoating layer comprising a thermosetting resin, an ultraviolet light-curable resin, or a combination thereof, and

wherein the overcoating layer is disposed on at least one of the first conductive layer and the second conductive layer.

9. The electrical conductor of claim 4, wherein the electrical conductor further comprises a transparent substrate that is disposed on an opposite second surface of the first conductive layer.

10. The electrical conductor of claim 1, wherein the electrical conductor is a transparent conductive film.

11. The electrical conductor of claim 1, wherein the first conductive layer is a discontinuous layer comprising spatially separated ruthenium oxide nanosheets of the plurality of ruthenium oxide nanosheets, and

wherein the ruthenium oxide nanosheets cover at least about 50% of a total area of the first conductive layer.

12. The electrical conductor of claim 1, wherein the electrical conductor has a transmittance of greater than or equal to about 85% at a thickness of a first conductive layer of 100 nanometers or less, with respect to light having a wavelength of 550 nanometers, and

wherein the electrical conductor has sheet resistance of less than or equal to about 1.2 ×

10⁴ ohms per square.

13. The electrical conductor of claim 1, wherein the electrical conductor has a resistance change of less than or equal to about 60% after folding 200,000 times at a curvature radius of 1 millimeter.

14. A method of preparing the electrical conductor of claim 1, the method comprising:

heat-treating a mixture of a ruthenium oxide and an alkali metal compound to prepare an alkali metal-substituted layered ruthenium oxide;

treating the alkali metal-substituted layered ruthenium oxide with an acidic solution to prepare a proton exchanged layered ruthenium oxide, wherein at least a portion of the alkali metal is replaced with a proton;

contacting the proton exchanged layered ruthenium oxide with a C1 to C20 alkyl ammonium compound to prepare a C1 to C20 alkyl ammonium-layered ruthenium oxide;

mixing the alkyl ammonium-layered ruthenium oxide with a solvent to obtain an exfoliated ruthenium oxide nanosheet;

conducting a surface doping to obtain the plurality of surface-doped ruthenium oxide nanosheets; and

applying a composition comprising the plurality of the surface-doped ruthenium oxide nanosheets on a surface of a substrate to form a first conductive layer; and

wherein the surface doping comprises adding the alkali metal- substituted layered ruthenium oxide, the proton exchanged layered ruthenium oxide, or the exfoliated ruthenium oxide nanosheet to an aqueous solution comprising a ruthenium halide, a ruthenium chalcogenide, an alkali metal halide, an ammonium halide, or a ruthenium-Group 15 element compound to form a mixture, and heating the mixture at a temperature of greater than or equal to about 100°

C.,

wherein the plurality of ruthenium oxide nanosheets have an average lateral size of greater than or equal to about 0.1 micrometers and less than or equal to about 100 micrometers, and a thickness of less than or equal to about 3 nanometers.

15. The method of claim 14, further comprising applying a composition comprising conductive metal nanowires on a surface of the first conductive layer.

16. The method of claim 14, wherein the surface doping is conducted with the alkali metal substituted layered ruthenium oxide, and

wherein the method further comprises drying the plurality of ruthenium oxide nanosheets.

17. The method of claim 16, wherein the surface doping is conducted with the exfoliated ruthenium oxide nanosheet and

wherein the method further comprises dispersing a surface-doped product in a mixture of a solvent and a C1 to C20 alkyl ammonium compound to prepare a re-exfoliated ruthenium oxide nanosheet.

18. An electronic device comprising the electrical conductor of claim 1.

19. The electronic device of claim 18, wherein the electronic device is a flat panel display, a touch screen panel, a solar cell, an e-window, an electrochromic mirror, a heat mirror, a transparent transistor, or a flexible display.