Nanostructures having high performance thermoelectric properties
The invention provides for a nanostructure, or an array of such nanostructures, each comprising a rough surface, and a doped or undoped semiconductor. The nanostructure is an one-dimensional (1-D) nanostructure, such a nanowire, or a two-dimensional (2-D) nanostructure. The nanostructure can be placed between two electrodes and used for thermoelectric power generation or thermoelectric cooling.
1. A thermoelectric device, comprising:
a first electrode;
a second electrode; and
one or more silicon nanowires located between the first electrode and the second electrode;
wherein each of the one or more silicon nanowires is in electrical contact with the first electrode and the second electrode and has a mean surface roughness ranging from 1 nm to 5 nm.
2. The device of claim 1 wherein the each of the one or more silicon nanowires has a diameter of less than 300 nm.
3. The device of claim 1 wherein the each of the one or more silicon nanowires has a diameter of less than 200 nm.
4. The device of claim 1 wherein the each of the one or more silicon nanowires has a diameter of less than 100 nm.
5. The device of claim 1 wherein the each of the one or more silicon nanowires has a diameter of about 5 to 50 nm.
6. The device of claim 1 wherein the each of the one or more silicon nanowires is doped to a carrier density of at least about 10 18 cm −3 .
7. The device of claim 1 wherein the each of the one or more silicon nanowires is doped to a carrier density of about 10 19 cm −3 .
8. The device of claim 1 wherein:
the first electrode includes a first opaque material;
the second electrode includes a second opaque material; and
the first opaque material and the second opaque material are the same or different.
9. The device of claim 1 wherein the device is configured to generate an electric current.
10. The device of claim 9 wherein the device is further configured to generate the electric current flowing between the first electrode and the second electrode through the one or more silicon nanowires, in response to the first electrode and the second electrode being at different temperatures.
11. The device of claim 9 wherein the device is further configured to, in response to the first electrode being at a higher temperature than the second electrode, generate the electric current flowing from the first electrode to the one or more silicon nanowires and through the one or more silicon nanowires to the second electrode.
12. The device of claim 1 wherein the device is configured to provide thermal-electric cooling.
13. The device of claim 1 wherein the device is configured to provide thermal-electric heating.
14. A thermoelectric device, comprising:
a first electrode;
a second electrode;
a third electrode; and
one or more first silicon nanowires located between the first electrode and the second electrode; and
one or more second silicon nanowires located between the second electrode and the third electrode;
wherein:
each of the one or more first silicon nanowires is in electrical contact with the first electrode and the second electrode and has a mean surface roughness ranging from 1 nm to 5 nm;
each of the one or more second silicon nanowires is in electrical contact with the second electrode and the third electrode and has a mean surface roughness ranging from 1 nm to 5 nm.
15. The device of claim 14 wherein the device is configured to generate an electric current.
16. The device of claim 15 wherein the device is further configured to generate the electric current flowing between the first electrode and the third electrode through the one or more first silicon nanowires, the second electrode, and the one or more second silicon nanowires, in response to the second electrode being at a different temperature from the first electrode and the third electrode.
17. The device of claim 15 wherein the device is further configured to generate, in response to the second electrode being at a higher temperature than the first electrode and the third electrode, the electric current flowing from the third electrode to the one or more second silicon nanowires, through the one or more second nanostructures to the second electrode, through the second electrode to the one or more first silicon nanowires, and through the one or more first silicon nanowires to the first electrode.
18. The device of claim 14 wherein the one or more first silicon nanowires are doped with one or more valence-five elements.
19. The device of claim 14 wherein the one or more second silicon nanowires are doped with one or more valence-three elements.
20. The device of claim 14 wherein the device is configured to provide thermal-electric cooling.
21. The device of claim 14 wherein the device is configured to provide thermal-electric heating.
22. The device of claim 14 wherein:
the first electrode includes a first opaque material;
the second electrode includes a second opaque material; and
the first opaque material and the second opaque material are the same or different.
23. A thermoelectric device, comprising:
a first electrode;
a second electrode;
a third electrode; and
one or more silicon nanowires located between the first electrode and the second electrode; and
one or more thermal-electric structures located between the second electrode and the third electrode;
wherein:
each of the one or more silicon nanowires is in electrical contact with the first electrode and the second electrode and has a mean surface roughness ranging from 1 nm to 5 nm; and
each of the one or more thermal-electric structures is in electrical contact with the second electrode and the third electrode.
24. The device of claim 23 wherein the device is configured to generate an electric current.
25. The device of claim 24 wherein the device is further configured to generate the electric current flowing between the first electrode and the third electrode through the one or more silicon nanowires, the second electrode, and the one or more thermal-electric structures, in response to the second electrode being at a different temperature from the first electrode and the third electrode.
26. The device of claim 23 wherein the device is configured to provide thermal-electric cooling.
27. The device of claim 23 wherein the device is configured to provide thermal-electric heating.
28. The device of claim 23 wherein:
the first electrode includes a first opaque material;
the second electrode includes a second opaque material; and
the first opaque material and the second opaque material are the same or different.