Method for making a CaTiO composite thin film electrode for water splitting

Patent metadata

Field	Value
Publication number	US-11761101-B2
Application number	US-202217938410-A
Country	US
Kind code	B2
Filing date	Oct 6, 2022
Priority date	May 2, 2019
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

A CaTiO3—TiO2 composite electrode and method of making is described. The composite electrode comprises a substrate with an average 2-12 μm thick layer of CaTiO3—TiO2 composite particles having average diameters of 0.2-2.2 μm. The method of making the composite electrode involves contacting the substrate with an aerosol comprising a solvent, a calcium complex, and a titanium complex. The CaTiO3—TiO2 composite electrode is capable of being used in a photoelectrochemical cell for water splitting.

First claim

The invention claimed is:

1. A method of making a CaTiO composite thin film electrode for water splitting, the method comprising:
contacting an aerosol with a conductive transparent substrate to deposit a crystalline CaTiO 3 -TiO 2 composite layer on the conductive transparent substrate to form the CaTiO composite thin film electrode,
wherein the aerosol comprises a carrier gas and a calcium complex and a titanium complex dissolved in a solvent, and
wherein the conductive transparent substrate has a temperature in a range of 400- 650° C. during the contacting,
wherein the CaTiO composite thin film electrode, comprises
the crystalline CaTiO 3 -TiO 2 composite layer having an average thickness of 2-12 μm adjacent the conductive transparent substrate, the crystalline CaTiO 3 -TiO 2 composite layer comprising crystalline CaTiO 3 -TiO 2 particles having an average diameter of 0.2-2.2 μm,
wherein the crystalline CaTiO 3 -TiO 2 composite layer comprises 25-87 wt % CaTiO 3 and 13-75 wt % TiO 2 , each relative to a total weight of the crystalline CaTiO 3 -TiO 2 composite layer.

2. The method of claim 1 , wherein the crystalline CaTiO 3 -TiO 2 composite layer comprises 80-85 wt % CaTiO 3 and 15-20 wt % TiO 2 , each relative to a total weight of the crystalline CaTiO 3 -TiO 2 composite layer.

3. The method of claim 1 , wherein the crystalline CaTiO 3 -TiO 2 particles of the crystalline CaTiO 3 -TiO 2 composite layer are substantially spherical.

4. The method of claim 1 , wherein the TiO 2 of the crystalline CaTiO 3 -TiO 2 composite layer is in anatase phase.

5. The method of claim 1 , wherein the CaTiO composite thin film electrode has a direct band gap value in a range of 2.5-3.5 eV.

6. The method of claim 1 , wherein the conductive transparent substrate is a transparent conducting film selected from the group consisting of ITO, FTO, AZO, GZO, IZO, IZTO, IAZO, IGZO, IGTO, and ATO.

7. The method of claim 1 , wherein the conductive transparent substrate has a sheet resistance in a range of 1-40 Ω sq 31 1 .

8. The method of claim 1 , wherein the calcium complex comprises trifluoroacetate ligands, acetate ligands, isopropanol ligands, and tetrahydrofuran ligands.

9. The method of claim 8 , wherein the calcium complex has a formula [Ca 2 (TFA) 3 (OAc))( i PrOH)(H 2 O)(THF) 3 ].

10. The method of claim 1 , wherein before the contacting, the aerosol consists essentially of the carrier gas, the calcium complex, the titanium complex, and the solvent.

11. The method of claim 1 , wherein the calcium complex and the solvent are present in the aerosol at a weight ratio of 1:1000-1:5.

12. The method of claim 1 , wherein the titanium complex and the solvent are present in the aerosol at a weight ratio of 1:10,000-1:5.

13. The method of claim 1 , wherein the aerosol is contacted with the conductive transparent substrate for a time period of 10-120 min.

14. The method of claim 1 , wherein during the contacting, the carrier gas has a flow rate in a range of 20-250 mL/min.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Ehsan Muhammad Ali
• Rehman Abdul

Classifications

• C25B1/04 Primary

  by electrolysis of water · CPC title

• C25B11/0773 Primary

  of the perovskite type · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• C25B1/55

  Photoelectrolysis · CPC title

• Y02P20/133

  Renewable energy sources, e.g. sunlight · CPC title