Thermoelectric material element, power generation device, optical sensor, and method for manufacturing thermoelectric material

Patent metadata

Field	Value
Publication number	US-2020403136-A1
Application number	US-201916977666-A
Country	US
Kind code	A1
Filing date	Feb 15, 2019
Priority date	Mar 8, 2018
Publication date	Dec 24, 2020
Grant date	—

Abstract

A thermoelectric material element includes: a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode. During the operation, the thermoelectric material portion includes a first temperature region having a first temperature, and a second temperature region having a second temperature lower than the first temperature of the first temperature region. A ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.

First claim

1 . A thermoelectric material element comprising:
a thermoelectric material portion composed of a thermoelectric material that includes a first crystal phase and a second crystal phase during an operation, the second crystal phase being different from the first crystal phase; a first electrode disposed in contact with the thermoelectric material portion; and a second electrode disposed in contact with the thermoelectric material portion and disposed to be separated from the first electrode, wherein during the operation, the thermoelectric material portion includes
a first temperature region having a first temperature, and
a second temperature region having a second temperature lower than the first temperature of the first temperature region, and
a ratio of the first crystal phase to the second crystal phase in the first temperature region is larger than a ratio of the first crystal phase to the second crystal phase in the second temperature region.

2 . The thermoelectric material element according to claim 1 , wherein
the first temperature region includes a maximum temperature portion having a highest temperature, the second temperature region includes a minimum temperature portion having a lowest temperature, and the ratio of the first crystal phase to the second crystal phase becomes smaller from the maximum temperature portion toward the minimum temperature portion.

3 . The thermoelectric material element according to claim 2 , wherein during the operation, a direction from the maximum temperature portion toward the minimum temperature portion is inclined relative to a direction from a region at which the first electrode and the thermoelectric material portion are in contact with each other toward a region at which the second electrode and the thermoelectric material portion are in contact with each other.

4 . The thermoelectric material element according to claim 1 , wherein in a compound of which the thermoelectric material portion is composed, a ratio of cation atoms included in the first crystal phase is different from a ratio of cation atoms included in the second crystal phase.

5 . The thermoelectric material element according to claim 1 , wherein a carrier concentration in the second crystal phase during the operation is lower than a carrier concentration in the second crystal phase before the operation.

6 . The thermoelectric material element according to claim 1 , wherein at least a portion of a surface of the thermoelectric material portion is exposed to a reduced pressure.

7 . The thermoelectric material element according to claim 6 , wherein at least the portion of the surface of the thermoelectric material portion is exposed to an atmospheric pressure of less than 10 Pa.

8 . The thermoelectric material element according to claim 1 , wherein during the operation, a temperature difference is less than 2 K between a region at which the first electrode and the thermoelectric material portion are in contact with each other and a region at which the second electrode and the thermoelectric material portion are in contact with each other.

9 . The thermoelectric material element according to claim 1 , wherein the thermoelectric material portion is composed of a chalcogenide.

10 . The thermoelectric material element according to claim 1 , wherein the thermoelectric material portion is composed of Cu 2 Se, SnSe, Ag 2 Se, Ag 2 Te, or a compound obtained by adding a transition metal element to one of the Cu 2 Se, the SnSe, the Ag 2 Se, the Ag 2 Te.

11 . The thermoelectric material element according to claim 10 , wherein
the thermoelectric material portion is composed of a compound obtained by adding Ni, Ti, or Zr to the Cu 2 Se.

12 . The thermoelectric material element according to claim 10 , wherein the thermoelectric material portion is composed of a compound obtained by adding Sc, Ti, or Zr to the SnSe.

13 . The thermoelectric material element according to claim 1 , wherein
the thermoelectric material portion is composed of Cu 2 Se, and the thermoelectric material portion has a temperature falling within a range of 50° C. to 130° C. during the operation.

14 . The thermoelectric material element according to claim 1 , wherein
the thermoelectric material portion is composed of SnSe, and the thermoelectric material portion has a temperature falling within a range of 130° C. to 530° C. during the operation.

15 . The thermoelectric material element according to claim 1 , wherein the first crystal phase is a cubic or orthorhombic crystal.

16 . A power generation device comprising the thermoelectric material element recited in claim 1 .

17 . An optical sensor comprising the thermoelectric material element recited in claim 1 .

18 . A method for manufacturing a thermoelectric material, the method comprising:
obtaining a pressed powder body by solidifying powder serving as a source material of a chalcogenide; crystallizing a portion of the pressed powder body by heating; and crystallizing a remainder of the pressed powder body by self-heating of the pressed powder body with the heating being halted after crystallizing the portion of the pressed powder body, the self-heating of the pressed powder body resulting from progress of crystallization.

Assignees

• Sumitomo Electric Industries
• Toyota School Found

Inventors

• Adachi Masahiro
• Kiyama Makoto
• Matsuura Takashi
• Yamamoto Yoshiyuki
• Byeon Do-Gyun
• Takeuchi Tsunehiro

Classifications

• H02N11/00

  Generators or motors not provided for elsewhere; Alleged perpetua mobilia obtained by electric or magnetic means (by hydrostatic pressure F03B17/04; {by mechanical means F03G7/10;} by dynamo-electric means, {including arrangements of permanent magnets interacting with other permanent magnets,} H02K53/00) · CPC title

• G01J1/02

  Details · CPC title

• H01L35/26

  Electricity · mapped topic

• H01L35/16

  Electricity · mapped topic

• H01L35/34 Primary

  Electricity · mapped topic