Higher manganese silicide based telluride composite for thermoelectric conversion and preparation method thereof

Patent metadata

Field	Value
Publication number	US-10892394-B2
Application number	US-201816043249-A
Country	US
Kind code	B2
Filing date	Jul 24, 2018
Priority date	Jul 28, 2017
Publication date	Jan 12, 2021
Grant date	Jan 12, 2021

Abstract

Provided is a higher manganese silicide based telluride composite for thermoelectric conversion, represented by the following general formula (1):

(MnsSi 1.740±0.015 ) 1−x (MnTe) x   (1)

wherein x is the molar fraction of manganese telluride in the higher manganese silicide based telluride composite for thermoelectric conversion and satisfies the relation 0<x≤0.10, and the maximum ZT value is 0.40 or more.

First claim

The invention claimed is:

1. A higher manganese silicide based telluride composite for thermoelectric conversion represented by the following general formula (1):
(MnSi 1.740±0.015 ) 1−x (MnTe) x   (1)

wherein
x is the molar fraction of manganese telluride in the higher manganese silicide based telluride composite for thermoelectric conversion and satisfies the relation 0<x≤0.10, and
a maximum ZT value of the higher manganese silicide based telluride composite for thermoelectric conversion is 0.40 or more.

2. The higher manganese silicide based telluride composite for thermoelectric conversion according to claim 1 , wherein
the composite has a manganese telluride/higher manganese silicide nanoblock composite structure, and
the maximum ZT value is 0.55 or more.

3. A preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion represented by the following general formula (1):
(MnSi 1.740±0.015 ) 1−x (MnTe) x   (1)

wherein
x is the molar fraction of manganese telluride in the higher manganese silicide based telluride composite for thermoelectric conversion and satisfies the relation 0<x≤0.10, and
a maximum ZT value of the higher manganese silicide based telluride composite for thermoelectric conversion is 0.40 or more; and
the preparation method comprising the following steps:
obtaining a powdery raw material mixture by mixing a manganese raw material, a silicon raw material, and a tellurium raw material in a predetermined ratio and then ball milling the resulting mixture for 1 to 10 hours by using at least one selected from liquid alkanes having 5 to 7 carbon atoms as a medium;
drying the powdery raw material mixture; and
obtaining the higher manganese silicide based telluride composite for thermoelectric conversion by sintering the raw material mixture after drying.

4. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 3 , wherein the medium is at least one selected from n-pentane, n-hexane and n-heptane.

5. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 3 , wherein
the Te raw material is Te nanowires,
the diameters of the Te nanowires are distributed in a range from 20 to 60 nm, and
the aspect ratios of the Te nanowires are 200 or more.

6. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 5 , wherein the Te nanowires have been subjected to a surface modification with at least one selected from alcohols having 1 to 5 carbon atoms.

7. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 6 , wherein the alcohols are at least one selected from methanol, ethanol, propanol, butanol, and pentanol.

8. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 5 , wherein the sintering is performed in an oxygen-free atmosphere at 950 to 1100° C.

9. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 3 , wherein the sintering is performed at 950 to 1100° C. for 5 to 120 minutes.

10. The preparation method of a higher manganese silicide based telluride composite for thermoelectric conversion according to claim 3 , wherein the sintering is performed under a condition that the axial direction pressure is 20 to 100 MPa.

Assignees

• Toyota Motor Co Ltd
• Univ Tsinghua

Inventors

• Li Jing-Feng
• Li Zhiliang
• Dong jin-feng
• Hirono Shinsuke

Classifications

• C01B19/007 Primary

  Tellurides or selenides of metals (C01B19/002 takes precedence) · CPC title

• C22C1/051

  Making hard metals based on borides, carbides, nitrides, oxides or silicides; Preparation of the powder mixture used as the starting material therefor · CPC title

• C01P2004/64

  Nanometer sized, i.e. from 1-100 nanometer · CPC title

• C22C1/10

  Alloys containing non-metals (C22C1/05, C22C1/08 take precedence) · CPC title

• C22C29/18

  based on silicides · CPC title