Cathode material for a solid oxide fuel cell and method for making the same

Patent metadata

Field	Value
Publication number	US-10686194-B2
Application number	US-201715838435-A
Country	US
Kind code	B2
Filing date	Dec 12, 2017
Priority date	Nov 29, 2017
Publication date	Jun 16, 2020
Grant date	Jun 16, 2020

Abstract

A cathode material for a solid oxide fuel cell comprises a perovskite type complex oxide which is represented by Formula 1: Gd 1-x M x CoO 3-δ .In Formula 1, M represents an alkali metal, x is larger than 0 and not more than 0.75, and δ ranges from 0 to 2.

First claim

What is claimed is:

1. A cathode material for a solid oxide fuel cell, comprising a perovskite type complex oxide represented by Formula 1:
Gd 1-x M x CoO 3-δ   Formula 1

wherein
M represents an alkali metal;
x is larger than 0 and not more than 0.030; and
δ ranges from 0 to 2.

2. The cathode material according to claim 1 , wherein M is sodium and x ranges from 0.005 to 0.030.

3. The cathode material according to claim 1 , wherein M is potassium and x ranges from 0.005 to 0.025.

4. A method for making a cathode material for a solid oxide fuel cell, comprising steps of:
a) processing a first mixture which includes gadolinium oxide, cobalt oxide, and an alkali metal precursor containing an alkali metal to obtain a perovskite type complex oxide represented by Formula 1:
Gd 1-x M x CoO 3-δ   Formula 1

wherein
M represents an alkali metal,
x is larger than 0 and not more than 0.030, and
δ ranges from 0 to 2;
b) grinding the perovskite type complex oxide into a powder;
c) mixing the powder and a binder to obtain a second mixture;
d) processing the second mixture to obtain a green compact; and
e) sintering the green compact to obtain the cathode material.

5. The method according to claim 4 , wherein step a) is performed by calcination.

6. The method according to claim 4 , wherein the alkali metal precursor is selected from the group consisting of sodium carbonate, sodium nitrate, sodium hydroxide, sodium ethoxide, sodium hydrocarbonate, sodium peroxide, potassium carbonate, potassium nitrate, potassium hydroxide, potassium nitrite, potassium chloride, and combinations thereof.

7. The method according to claim 4 , wherein M is sodium, and a molar ratio of sodium contained in the alkali metal precursor to gadolinium contained in gadolinium oxide is in a range from 5×10 −3 to 31×10 −3 .

8. The method according to claim 4 , wherein M is potassium, and a molar ratio of potassium contained in the alkali metal precursor to gadolinium contained in gadolinium oxide is in a range from 5×10 −3 to 26×10 −3 .

9. The method according to claim 4 , wherein the binder is selected from the group consisting of polyvinyl alcohol, paraffin wax, polyethylene, polypropylene, polystyrene, poly(methyl methacrylate), ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and combinations thereof.

10. The method according to claim 4 , wherein step d) is performed by isostatic pressing.

11. The method according to claim 4 , wherein step e) is performed at a sintering temperature ranging from 1150° C. to 1350° C.

Assignees

• Univ Nat Taipei Technology

Inventors

• Wang Sea-Fue
• Liu yi-xin
• Lin Tung

Classifications

• C04B35/01 Primary

  based on oxide ceramics · CPC title

• Y02E60/50

  Fuel cells · CPC title

• C04B35/00

  Shaped ceramic products characterised by their composition {(porous ceramic products C04B38/00; ceramic articles characterised by particular shape, see the relevant classes, e.g. linings for casting ladles, tundishes, cups or the like B22D41/02; ceramic substrates for microelectronic semi-conductors H10W70/692)}; Ceramics compositions ({shaping of ceramics B28B;} containing free metal bonded to carbides, diamond, oxides, borides, nitrides, silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides or sulfides other than as macroscopic reinforcing agents C22C); Processing powders of inorganic compounds preparatory to the manufacturing of ceramic products {(infiltration of sintered ceramic preforms with molten metal C04B41/51; chemical preparation of powders of inorganic compounds C01)} · CPC title

• C04B35/63424

  Polyacrylates; Polymethacrylates · CPC title

• C04B2235/3275

  Cobalt oxides, cobaltates or cobaltites or oxide forming salts thereof, e.g. bismuth cobaltate, zinc cobaltite · CPC title