Chalcogen-containing compound, its preparation method and thermoelectric element comprising the same

Patent metadata

Field	Value
Publication number	US-2019334071-A1
Application number	US-201816462179-A
Country	US
Kind code	A1
Filing date	Jun 5, 2018
Priority date	Jun 7, 2017
Publication date	Oct 31, 2019
Grant date	—

Abstract

A chalcogen-containing compound of the following Chemical Formula 1 which exhibits excellent phase stability even at a low temperature, particularly at a temperature corresponding to an operating temperature of a thermoelectric element, and also exhibits a significantly superior power factor and thermoelectric performance index due to its excellent electrical conductivity and low thermal conductivity caused by its unique crystal lattice structure, a method for preparing the same, and a thermoelectric element including the same. [Chemical Formula 1]—V1-2xSn4Bi2-xAg3xSe7, wherein V is vacancy and 0<x<0.5.

First claim

1 . A chalcogen-containing compound represented by the following Chemical Formula 1:
V 1-2x Sn 4 Bi 2-x Ag 3x Se 7   [Chemical Formula 1]
wherein, in the above Chemical Formula 1, V is vacancy and 0<x<0.5.

2 . The chalcogen-containing compound of claim 1 , wherein x is 0.05≤x≤0.4.

3 . The chalcogen-containing compound of claim 1 , wherein the compound has a face-centered cubic crystal lattice structure.

4 . The chalcogen-containing compound of claim 3 , wherein the vacancy is a vacant site excluding sites filled with Se, Sn, Bi, and Te in the face-centered cubic lattice structure, and the Ag is substituted by replacing a part of the Bi.

5 . The chalcogen-containing compound of claim 3 , wherein the Se is filled in an anion site of the face-centered cubic lattice structure, the Sn and Bi are filled in a cationic site of the face-centered cubic lattice structure, the vacancy is a vacant site of the remaining sites excluding the sites filled with Se, Sn, and Bi, and the Ag is substituted by replacing a part of the Bi.

6 . A thermoelectric conversion material comprising the chalcogen-containing compound according to claim 1 .

7 . A method for preparing the chalcogen-containing compound according to claim 1 , comprising the steps of:
mixing raw materials of Sn, Bi, Ag, and Se and then melting the raw materials to prepare a melt; heat-treating the melt; pulverizing the resultant product obtained through the heat treatment; and sintering the pulverized product.

8 . The method for preparing the chalcogen-containing compound of claim 7 , wherein the raw materials of Sn, Bi, Ag, and Se are mixed at a molar ratio of Sn:Bi:Ag:Se corresponding to 4:2-x:3x:7, and the x is 0<x<0.5.

9 . The method for preparing the chalcogen-containing compound of claim 7 , wherein the melting is carried out at a temperature of 750 to 1000° C.

10 . The method for preparing the chalcogen-containing compound of claim 7 , wherein the heat treatment is carried out at a temperature of 500 to 700° C.

11 . The method for preparing the chalcogen-containing compound of claim 7 , further comprising a step of cooling the resultant of the heat treatment step to form an ingot between the heat treatment step and the pulverization step.

12 . The method for preparing the chalcogen-containing compound of claim 7 , wherein the sintering step is carried out by a spark plasma sintering method.

13 . The method for preparing the chalcogen-containing compound of claim 7 , wherein the sintering step is carried out at a temperature of 550 to 700° C. under a pressure of 10 to 130 MPa.

14 . A thermoelectric element comprising the chalcogen-containing compound according to claim 1 .

Assignees

• Lg Chemical Ltd

Inventors

• Kim Min Kyoung
• Min Yu Ho
• Park Cheol Hee
• Ko Kyung Moon
• Park Chee Sung
• Jung Myung Jin

Classifications

• C01P2002/77

  by unit-cell parameters, atom positions or structure diagrams · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01P2006/32

  Thermal properties · CPC title

• H01L35/16 Primary

  Electricity · mapped topic