Method for producing perovskite compound, and perovskite compound

Patent metadata

Field	Value
Publication number	US-12240764-B2
Application number	US-202117912738-A
Country	US
Kind code	B2
Filing date	Feb 10, 2021
Priority date	Mar 30, 2020
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

Provided is a method of producing fine particulate barium calcium titanate in which calcium forms a homogeneous solid solution. The present invention relates to a method of producing a perovskite compound represented by the following formula (1):

Ba (1-x) A x TiO 3   (1)
wherein A represents Ca or Sr, and x is a number satisfying 0.00<x≤0.30,
the method including: a first step of acid washing barium titanate to provide barium titanate having a ratio of barium element to titanium element of lower than 1.00; a second step of mixing the barium titanate obtained in the first step and a calcium salt or a strontium salt and drying the mixture to provide a dry mixture; and a third step of heating the dry mixture obtained in the second step.

First claim

The invention claimed is:

1. A method of producing a perovskite compound represented by the following formula (1):
Ba (1-x) A x TiO 3   (1)

wherein A represents Ca or Sr, and x is a number satisfying 0.00<x≤0.30,
the method comprising:
acid washing barium titanate so as to obtain barium titanate having a ratio of barium element to titanium element of lower than 1.00;
mixing the barium titanate having a ratio of barium element to titanium element of lower than 1.00 obtained in the acid washing, and a calcium salt or a strontium salt;
drying the mixture so as to obtain a dry mixture; and
heating the dry mixture so as to obtain the perovskite compound.

2. The method of producing a perovskite compound according to claim 1 ,
wherein the barium titanate having the ratio of barium element to titanium element of lower than 1.00 obtained in the acid washing has a Brunauer-Emmett-Teller (BET) specific surface area in a range from 20 to 130 m 2 /g.

3. The method of producing a perovskite compound according to claim 1 , further comprising
breaking up agglomerated particles of the perovskite compound obtained in the heating the dry mixture by heating the obtained perovskite compound in a solvent at a temperature in a range from 30° C. to 500° C.

Assignees

• Sakai Chemical Industry Co

Inventors

• KAWATAKI Takahiro
• Mizutani Hideto
• Yano Seiichi

Classifications

• H01G4/1227

  based on alkaline earth titanates · CPC title

• C01P2006/40

  Electric properties · CPC title

• C01P2006/12

  Surface area · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title

• C01P2004/03

  obtained by SEM · CPC title