Alkaline earth metal titanate crystal laminate

Patent metadata

Field	Value
Publication number	US-2020346941-A1
Application number	US-201816647333-A
Country	US
Kind code	A1
Filing date	Sep 14, 2018
Priority date	Sep 15, 2017
Publication date	Nov 5, 2020
Grant date	—

Abstract

There are provided a new type of crystal laminate of an alkaline earth metal titanate having improved catalytic activity, and a method for producing the same. The crystal laminate is provided having a crystal of the alkaline earth metal titanate as a constitutional unit, wherein the crystal being the constitutional unit is a cubic crystal, a tetragonal crystal or an orthorhombic crystal; the crystal being the constitutional unit has a primary particle diameter of 500 nm or less; and the crystal is layered with an orientation in a {100} plane direction thereof.

First claim

1 . A crystal laminate, comprising:
a crystal of an alkaline earth metal titanate as a constitutional unit, wherein: the crystal is a cubic crystal, a tetragonal crystal or an orthorhombic crystal; the crystal has a primary particle diameter of 500 nm or less; and the crystal is layered with an orientation in a {100} plane direction thereof.

2 . The crystal laminate according to claim 1 , wherein the crystal laminate has an average width of 1 μm or more.

3 . The crystal laminate according to claim 1 , wherein the crystal laminate has an average thickness of 50 nm or more.

4 . The crystal laminate according to claim 1 , wherein the crystal present on a surface of the crystal laminate has a primary particle diameter more than a primary particle diameter of the crystal present in an interior of the crystal laminate.

5 . The crystal laminate according to claim 1 , wherein the crystal laminate has a specific surface area of 10 m 2 /g or more.

6 . A structure having an alkaline earth metal titanate crystal nanoparticle on a surface of the crystal laminate according to claim 1 , wherein
a crystal orientation of the alkaline earth metal titanate crystal nanoparticle is in the same direction as that of the crystal laminate.

7 . The structure according to claim 6 , wherein the alkaline earth metal titanate crystal nanoparticle has a primary particle diameter of twice or more a primary particle diameter of the crystal present on the surface of the crystal laminate.

8 . The structure according to claim 6 , wherein the alkaline earth metal titanate crystal nanoparticle has a primary particle diameter of 50 nm or more.

9 . A method for producing a crystal laminate of an alkaline earth metal titanate, the method comprising:
subjecting a titanium oxide mesocrystal having a titanium oxide nanoparticle orderly layered therein and an alkaline earth metal atom source to a hydrothermal reaction.

Assignees

• Japan Science & Tech Agency

Inventors

• Tachikawa Takashi

Classifications

• B01J2235/15

  X-ray diffraction · CPC title

• B01J2235/30

  Scanning electron microscopy; Transmission electron microscopy · CPC title

• B01J35/733

  Perovskite-type · CPC title

• B01J35/393

  Metal or metal oxide crystallite size · CPC title

• B82Y30/00

  Nanotechnology for materials or surface science, e.g. nanocomposites · CPC title