Nanostructured layers of thermoelectric materials

Patent metadata

Field	Value
Publication number	US-9882108-B2
Application number	US-201615254412-A
Country	US
Kind code	B2
Filing date	Sep 1, 2016
Priority date	Sep 8, 2015
Publication date	Jan 30, 2018
Grant date	Jan 30, 2018

Abstract

This disclosure provides systems, methods, and apparatus related to thermoelectric materials. In one aspect, a method includes providing a plurality of nanostructures. The plurality of nanostructures comprise a thermoelectric material, with each nanostructure of the plurality of nanostructures having first ligands disposed on a surface of the nanostructure. The plurality of nanostructures is mixed with a solution containing second ligands and a ligand exchange process occurs in which the first ligands disposed on the plurality of nanostructures are replaced with the second ligands. The plurality of nanostructures is deposited on a substrate to form a layer. The layer is thermally annealed.

First claim

What is claimed is:

1. A method comprising:
(a) providing a plurality of nanostructures, the plurality of nanostructures comprising a thermoelectric material, each nanostructure of the plurality of nanostructures having first ligands disposed on a surface of the nanostructure;
(b) mixing the plurality of nanostructures with a solution containing second ligands and a ligand exchange process occurring in which the first ligands disposed on the plurality of nanostructures are replaced with the second ligands;
(c) depositing the plurality of nanostructures on a substrate to form a layer; and
(d) thermally annealing the layer.

2. The method of claim 1 , wherein the plurality of nanostructures comprises nanostructures selected from a group consisting of nanorods, nanowires, nanoparticles, and quantum dots.

3. The method of claim 1 , wherein the first ligands comprise oleylamine ligands.

4. The method of claim 1 , wherein the plurality of nanostructures comprises Cu 2 Se or Cu 2-x Se.

5. The method of claim 1 , wherein operation (c) is performed with a solution processing technique.

6. The method of claim 5 , wherein the solution processing technique is selected from a group consisting of spin coating, dip coating, spray coating, doctor blade, and inkjet printing.

7. The method of claim 1 , wherein the substrate comprises a silicon substrate or a glass substrate.

8. The method of claim 1 , wherein the second ligands comprise ethanedithiol ligands.

9. The method of claim 1 , wherein the first ligands have a longer chain length than the second ligands.

10. The method of claim 1 , wherein during the thermal annealing all of the second ligands are removed from the surface of each nanostructure of the plurality of nanostructures.

11. The method of claim 1 , wherein during the thermal annealing at least some of the second ligands are removed from the surface of each nanostructure of the plurality of nanostructures.

12. The method of claim 1 , wherein the thermal annealing is performed at a temperature below about 500° C.

13. The method of claim 1 , wherein the thermal annealing is performed for about 15 minutes to 1 hour.

14. The method of claim 1 , wherein the thermal annealing is performed in an atmosphere comprising a gas selected from a group consisting of nitrogen, argon, hydrogen, air, and mixtures thereof.

15. The method of claim 1 , wherein after the thermal annealing, a thermoelectric material surface of a first nanostructure is in contact with a thermoelectric material surface of a second nanostructure.

16. The method of claim 1 , wherein after the thermal annealing, the layer has a thermoelectric figure of merit (ZT) of at least about 0.3.

17. A method comprising:
(a) providing a plurality of nanostructures, the plurality of nanostructures comprising a thermoelectric material, each nanostructure of the plurality of nanostructures having first ligands disposed on a surface of the nanostructure;
(b) depositing the plurality of nanostructures on a substrate to form a layer;
(c) contacting the layer with a solution containing second ligands and a ligand exchange process occurring in which the first ligands disposed on the plurality of nanostructures are replaced with the second ligands; and
(d) thermally annealing the layer.

18. The method of claim 17 , wherein the plurality of nanostructures comprises Cu 2 Se or Cu 2-x Se, wherein the first ligands comprise oleylamine ligands, and wherein the second ligands comprise ethanedithiol ligands.

19. The method of claim 17 , wherein after the thermal annealing, the layer has a thermoelectric figure of merit (ZT) of at least about 0.3.

Assignees

• Urban Jeffrey J
• Lynch Jared
• Coates Nelson
• Forster Jason
• Sahu Ayaskanta
• Chabinyc Michael
• Russ Boris
• Univ California

Inventors

• Urban Jeffrey J
• Lynch Jared
• Coates Nelson
• Forster Jason
• Sahu Ayaskanta
• Chabinyc Michael
• Russ Boris

Classifications

• C01P2004/16

  Nanowires or nanorods, i.e. solid nanofibres with two nearly equal dimensions between 1-100 nanometer · CPC title

• H01L35/02

  Electricity · mapped topic

• C09D1/00

  Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances · CPC title

• H01L35/16 Primary

  Electricity · mapped topic

• C09D5/24

  Electrically-conducting paints {(conductive materials H01B1/00)} · CPC title