Electrolyte layer having a patchwork-type nanoporous grain boundary and a method of preparation thereof

Patent metadata

Field	Value
Publication number	US-9673470-B2
Application number	US-201414160948-A
Country	US
Kind code	B2
Filing date	Jan 22, 2014
Priority date	Jan 22, 2014
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

Gadolinium-doped cerium oxide slurries used to form a patchwork type surface structure with nanoporous grain boundary prepared by mixing gadolinium-doped cerium oxide and a polymer binder to form a first mixture; wet-atomizing the first mixture under a pressure of at least 100 MPa to obtain a second mixture; coating the second mixture to a substrate to form a coated substrate; and sintering the coated substrate. The patchwork type structure is a polygonal or honeycomb structure having a size of from 0.1 μm to 3 μm.

First claim

The invention claimed is:

1. A method for preparing a gadolinium-doped cerium oxide slurry having a patchwork surface structure with a nanoporous grain boundary, the method comprising:
mixing a gadolinium-doped cerium oxide and a polymer binder, thereby forming a first mixture having 12 to 20% by weight of the polymer binder;
wet-atomizing the first mixture under a pressure of 100 to 200 MPa, thereby obtaining a second mixture;
coating the second mixture on a substrate, thereby forming a coated substrate; and
sintering the coated substrate at a temperature of 1300 to 1450° C.,
wherein the patchwork structure has polygonal grains having a size of from 0.1 μm to 3 μm; and
wherein the nanoporous grain boundary is present on all surroundings of all of the polygonal grains.

2. The method of claim 1 , wherein the pressure during the wet atomizing is about 150 MPa.

3. The method of claim 1 , wherein the pressure during the wet atomizing is from 130 to 170 MPa.

4. The method of claim 1 , wherein the wet-atomizing is repeated up to 5 times.

5. The method of claim 1 , wherein the wet-atomizing is repeated 3 times.

6. The method of claim 1 , wherein the polymer binder is polyvinyl butyral.

7. The method of claim 1 , wherein the polymer binder is not polyvinyl pyrrolidinone.

8. The method of claim 1 , wherein the polymer binder is not polytetrafluoroethylene.

9. The method of claim 1 , wherein the first mixture further comprises ethanol and toluene as a solvent or suspension medium.

10. The method of claim 1 , wherein the first mixture further comprises an amine as a dispersant.

11. A gadolinium doped cerium oxide electrolyte prepared by the method of claim 1 .

12. The method of claim 1 , wherein the nanoporous grain boundary has nanopores with a diameter of from 0.01 μm to 0.7 μm.

13. The method of claim 1 , wherein the sintering is sintering at a temperature of from 1350 to 1425° C.

14. The method of claim 1 , wherein the first mixture has 14 to 18% by weight of the polymer binder.

15. The method of claim 1 , wherein the first mixture has about 16% by weight of the polymer binder.

16. The method of claim 1 , wherein the polygonal grains have a size of from 0.5 μm to 2 μm.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Zahir Md Hasan
• Bahaidarah Haitham M

Classifications

• H01M2300/0074

  Ion conductive at high temperature · CPC title

• C04B2235/5445

  submicron sized, i.e. from 0,1 to 1 micron · CPC title

• C04B41/87

  Ceramics · CPC title

• C04B2235/85

  Intergranular or grain boundary phases · CPC title

• C04B41/5045

  Rare-earth oxides · CPC title