Solid electrolyte, manufacturing method thereof, and gas sensor

Patent metadata

Field	Value
Publication number	US-11656196-B2
Application number	US-202016864256-A
Country	US
Kind code	B2
Filing date	May 1, 2020
Priority date	Nov 3, 2017
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

A solid electrolyte includes partially stabilized zirconia in which a stabilizer forms a solid solution in zirconia. The partially stabilized zirconia includes, as crystal particles that configure the partially stabilized zirconia, stabilizer low-concentration phase particles of which concentration of the stabilizer at a particle center is less than 4.7 mol % and stabilizer high-concentration phase particles of which the concentration of the stabilizer at the particle center is equal to or greater than 4.7 mol %. The partially stabilized zirconia includes an adjacent particle portion in which two or more particles of the stabilizer low-concentration phase particles of which an average particle size is greater than 0.1 μm are adjacent. An abundance ratio of the stabilizer high-concentration phase particles on a cross-section of the solid electrolyte is equal to or greater than 70% in terms of area ratio relative to all crystal particles.

First claim

What is claimed is:

1. A solid electrolyte comprising:
partially stabilized zirconia in which a stabilizer forms a solid solution in zirconia, wherein:
the partially stabilized zirconia comprises, as crystal particles that configure the partially stabilized zirconia, stabilizer low-concentration phase particles of which concentration of the stabilizer at a particle center is less than 4.7 mol % and stabilizer high-concentration phase particles of which the concentration of the stabilizer at the particle center is equal to or greater than 4.7 mol %, and comprises an adjacent particle portion in which two or more particles of the stabilizer low-concentration phase particles of which an average particle size is greater than 0.1 μm are adjacent; and
an abundance ratio of the stabilizer high-concentration phase particles on a cross-section of the solid electrolyte is equal to or greater than 70% in terms of area ratio relative to all crystal particles.

2. The solid electrolyte according to claim 1 , wherein:
the abundance ratio of the adjacent particle portions on a cross-section of the solid electrolyte is equal to or greater than 50% in terms of area ratio relative to the stabilizer low-concentration phase particles.

3. The solid electrolyte according to claim 2 , wherein:
the abundance ratio of the adjacent particle portions on a cross-section of the solid electrolyte is 8 to 16% in terms of area ratio relative to all crystal particles.

4. The solid electrolyte according to claim 3 , wherein:
an average particle size of the adjacent particle portions is 1 to 5 μm.

5. The solid electrolyte according to claim 4 , wherein:
an average particle size of the stabilizer high-concentration phase particle is 1 to 5 μm.

6. The solid electrolyte according to claim 5 , wherein:
the stabilizer comprises yttria.

7. The solid electrolyte according to claim 6 , further comprising:
a contacting portion that is configured such that the solid electrolyte is in contact with a dissimilar material member.

8. The solid electrolyte according to claim 7 , wherein:
the dissimilar material member comprises alumina or spinel.

9. The solid electrolyte according to claim 1 , wherein:
the abundance ratio of the adjacent particle portions on a cross-section of the solid electrolyte is 8 to 16% in terms of area ratio relative to all crystal particles.

10. The solid electrolyte according to claim 1 , wherein:
an average particle size of the adjacent particle portions is 1 to 5 μm.

11. The solid electrolyte according to claim 1 , wherein:
an average particle size of the stabilizer high-concentration phase particle is 1 to 5 μm.

12. The solid electrolyte according to claim 1 , wherein:
the stabilizer comprises yttria.

13. The solid electrolyte according to claim 1 , further comprising:
a contacting portion that is configured such that the solid electrolyte is in contact with a dissimilar material member.

14. The solid electrolyte according to claim 13 , wherein:
the dissimilar material member comprises alumina or spinel.

15. A gas sensor comprising:
a solid electrolyte according to claim 1 .

Assignees

• Denso Corp

Inventors

• Suzuki Satoshi
• Yoshida Mitsuhiro
• Noguchi Makoto

Classifications

• H01B1/08

  oxides · CPC title

• C04B2235/785

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

• C04B35/62695

  Granulation or pelletising (devices for shaping artificial aggregates from ceramic mixtures B28B1/004) · CPC title

• C04B2235/5445

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

• C04B35/64

  Burning or sintering processes (C04B33/32 takes precedence {; powder metallurgy B22F}) · CPC title