Semiconductor particles used in water-splitting photocatalyst, photocatalyst formed of semiconductor particles, and synthesis method thereof

Patent metadata

Field	Value
Publication number	US-12157110-B2
Application number	US-202217944557-A
Country	US
Kind code	B2
Filing date	Sep 14, 2022
Priority date	Sep 30, 2021
Publication date	Dec 3, 2024
Grant date	Dec 3, 2024

Abstract

Semiconductor particles are used as a photocatalyst for inducing a water-splitting reaction where water molecules decompose into oxygen molecules and hydrogen molecules by addition of a co-catalyst and light irradiation, the semiconductor particles including strontium titanate doped with scandium. A synthesis method of a semiconductor for the photocatalyst includes a synthesis step of synthesizing the semiconductor particles including strontium titanate doped with scandium by mixing strontium chloride (SrCl 2 ), strontium titanate (SrTiO 3 ), and scandium oxide (Sc 2 O 3 ) and firing the mixture.

First claim

What is claimed is:

1. A synthesis method of semiconductor particles including strontium titanate in a photocatalyst for inducing a water-splitting reaction where water molecules decompose into oxygen molecules and hydrogen molecules by light irradiation, the photocatalyst being formed by adding a co-catalyst to the semiconductor particles including strontium titanate, and the synthesis method comprising a synthesis step of synthesizing the semiconductor particles including strontium titanate doped with scandium and aluminum by mixing strontium chloride (SrCl 2 ), strontium titanate (SrTiO 3 ), scandium oxide (Sc 2 O 3 ), and aluminum oxide (Al 2 O 3 ) to obtain a mixture and firing the mixture,
wherein in the synthesis step, the scandium oxide is mixed at a molar ratio of 0.001 to 0.007 with respect to strontium titanate.

2. The synthesis method according to claim 1 , wherein in the synthesis step, aluminum oxide is mixed at a molar ratio of 0.02 with respect to strontium titanate.

3. The synthesis method according to claim 1 , wherein in the synthesis step, a firing temperature is 1150° C. to 1200° C. and a firing time is 10 hours to 30 hours.

4. A synthesis method of synthesizing a photocatalyst using semiconductor particles synthesized using the synthesis method according to claim 1 , the photocatalyst inducing a water-splitting reaction where water molecules decompose into oxygen molecules and hydrogen molecules by light irradiation, and the synthesis method of synthesizing the photocatalyst comprising an addition step of adding the co-catalyst to surfaces of the semiconductor particles dispersed in water.

5. The synthesis method according to claim 4 , wherein the co-catalyst is rhodium chromium oxide (Rh/Cr 2 O 3 ) and cobalt hydroxide oxide (CoOOH).

6. The synthesis method according to claim 5 , wherein in the addition step, the co-catalyst is added by photodeposition to the surfaces of the semiconductor particles dispersed in water.

7. The synthesis method according to claim 1 , wherein in the synthesis step, a firing temperature is 1185° C. to 1200° C. and a firing time is 10 hours to 30 hours.

8. The synthesis method according to claim 1 , wherein in the synthesis step, a firing temperature is 1185° C. to 1200° C. and a firing time is 15 hours to 30 hours.

9. The synthesis method according to claim 1 , wherein the aluminum oxide (Al 2 O 3 ) is mixed at a molar ratio of 0.02 with respect to the strontium titanate (SrTiO 3 ).

Assignees

• Toyota Motor Co Ltd
• Toyoda Gosei Kk
• Konan Gakuen

Inventors

• Masuda Taizo
• Tomizawa Ryota
• Hasegawa Tatsuya
• Ikeda Shigeru

Classifications

• B01J2235/00

  Indexing scheme associated with group B01J35/00, related to the analysis techniques used to determine the catalysts form or properties · CPC title

• B01J35/50

  characterised by their shape or configuration · CPC title

• B01J35/39 Primary

  Photocatalytic properties · CPC title

• B01J35/33

  Electric or magnetic properties · CPC title

• C01B3/042

  Decomposition of water (by electrolysis of water C25B1/04) · CPC title