Perovskite oxide catalyst having improved oxygen catalytic activity and preparation method thereof

Patent metadata

Field	Value
Publication number	US-11289709-B2
Application number	US-201815972584-A
Country	US
Kind code	B2
Filing date	May 7, 2018
Priority date	May 15, 2017
Publication date	Mar 29, 2022
Grant date	Mar 29, 2022

Abstract

Disclosed is a catalyst having a perovskite structure in the form of ABO 3 , in which the number of ion moles at the A site has an excess ratio compared to the number of ion moles at the B site. The present invention exhibits an oxygen catalytic activity improved by about 3 times in an oxygen evolution reaction and by about 40% in an oxygen reduction reaction, compared to those of an existing LaNiO 3 perovskite catalyst. Further, since the metallic conductivity is not significantly changed compared to the existing LaNiO 3 perovskite oxide, there is an advantage in that a carbon support need not be used when the present invention is used as a catalyst in a battery positive electrode.

First claim

What is claimed is:

1. A catalyst for the evolution and reduction of oxygen, the catalyst comprising a perovskite structure in a form of ABO 3 ,
wherein the number of ion moles at the A site has an excess ratio compared to the number of ion moles at the B site and the perovskite structure has a stacking fault that acts as an active site for oxygen generation, and
wherein A and B are lanthanum (La) and nickel (Ni), respectively, and the perovskite structure is provided as a film on a LaAlO 3 substrate.

2. The catalyst of claim 1 , wherein the excess ratio is 2 to 10%.

3. The catalyst of claim 1 , wherein the stacking fault is a fault formed by continuously facing a [LaO] + layer and a [LaO] + layer with each other.

4. The catalyst of claim 1 , wherein the stacking fault is present at a ratio of 10 to 15% based on a total unit cell of a perovskite compound.

5. The catalyst of claim 1 , wherein the stacking fault is formed in a thin film of the perovskite compound and on a surface thereof.

6. The catalyst of claim 1 , wherein the catalyst having the perovskite structure has a current density of 120 to 125 μA/cm 2 at 1.63 V (vs. RHE).

Assignees

• Korea Advanced Inst Sci & Tech

Inventors

• Chung Sung Yoon
• Bak Ju Mi

Classifications

• C01B13/02

  Preparation of oxygen (by liquefying F25J) · CPC title

• B01J37/08

  Heat treatment {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• B01J37/023

  using molten compounds · CPC title

• B01J37/04

  Mixing {(B01J37/0009, B01J37/0018 take precedence)} · CPC title

• B01J35/33

  Electric or magnetic properties · CPC title