Homogeneous cerium oxide-titanium oxide composite thin film

Patent metadata

Field	Value
Publication number	US-12492467-B2
Application number	US-202217818420-A
Country	US
Kind code	B2
Filing date	Aug 9, 2022
Priority date	Apr 30, 2019
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

A simple, one-step method for producing a homogenous CeO2—TiO2 composite thin film using aerosol-assisted chemical vapor deposition (“CVD”) of a solution containing triacetatocerium (III) and tetra isopropoxytitanium (IV) on a fluorine-doped tin oxide (“FTO”) substrate at a temperature ranging from about 500 to about 650° C. Methods for using the film produced by this method.

First claim

The invention claimed is:

1 . A homogenous CeO 2 -TiO 2 composite thin film, comprising
uniformly dispersed crystalline CeO 2 and TiO 2 phases, and mesoporous or smooth microspheres comprising CeO 2 and/or TiO 2 having an average diameter ranging from about 0.8 to 2.0 μm, wherein said thin film has a thickness of no more than 5 μm.

2 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 formed by a method comprising:
dispersing a solution of metal trifluoroacetates of cerium and titanium in a carrier gas to form an aerosol mist,
conducting aerosol-assisted chemical vapor deposition (“AACVD”) at a temperature in a range of from 500 to 650° C. with the aerosol mist,
contacting the aerosol mist, in the AACVD, with a fluorine-doped tin oxide substrate, thereby depositing the homogenous CeO 2 -TiO 2 composite film onto the fluorine-doped tin oxide substrate.

3 . The homogenous CeO 2 -TiO 2 composite thin film of claim 2 , wherein the method of making the homogenous CeO 2 -TiO 2 composite thin film further comprises:
reacting trifluoroacetic acid with triacetatocerium (III) and tetra isopropoxytitanium (IV) to form an initial solution of the metal trifluoroacetates; evaporating the initial solution to obtain a residue; and redissolving the residue in methanol to obtain the solution of metal trifluoroacetates of cerium and titanium as a methanol solution comprising the metal trifluoroacetates in a Ce:Ti molar ratio of 1.2:1 to 1:1.2.

4 . The homogenous CeO 2 -TiO 2 composite thin film of claim 3 , wherein in the method of making the homogenous CeO 2 -TiO 2 composite thin film, the reacting is conducted in methanol.

5 . The homogenous CeO 2 -TiO 2 composite thin film of claim 2 , wherein in the method of making the homogenous CeO 2 -TiO 2 composite thin film, the temperature of the AACVD and contacting are in a range of from 540 to 560° C. and wherein the thin film comprises the mesoporous microspheres having a pore size in a range of from 10 to 28 nm.

6 . The homogenous CeO 2 -TiO 2 composite thin film of claim 2 , wherein in the method of making the homogenous CeO 2 -TiO 2 composite thin film, the temperature of the AACVD and contacting are in a range of from 590 to 610° C., and wherein the thin film comprises the smooth microspheres with a substantially non-porous texture.

7 . The homogenous CeO 2 -TiO 2 composite thin film of claim 2 , wherein in the method of making the homogenous CeO 2 -TiO 2 composite thin film, the aerosol in the AACVD comprises a homogenous mixture of the metal trifluoroacetates in air, and the method comprises a single depositing.

8 . The homogenous CeO 2 -TiO 2 composite thin film of claim 7 , wherein the method of making the homogenous CeO 2 -TiO 2 composite thin film comprises no further dispersion, coating or heating.

9 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , comprising porous heterojunctions of CeO 2 -TiO 2 which have spherical-shaped morphologies.

10 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , having a bandgap less than either pristine CeO 2 or pristine TiO 2 .

11 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , having a bandgap ranging from 2.5 to 2.7 eV.

12 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , wherein the microspheres have an average diameter in a range of from 0.8 to 1.5 μm.

13 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , wherein the microspheres have an average diameter in a range of from 0.8 to 1.0 μm.

14 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , wherein the microspheres have an average Wadell sphericity value in a range of from 0.3 to 0.9.

15 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , wherein the microspheres have an average Wadell sphericity value in a range of from 0.3 to 0.8.

16 . The homogenous CeO 2 -TiO 2 composite thin film of claim 1 , wherein the microspheres comprise the Ce and the Ti in an atomic ratio of 0.7:1.0.

Assignees

• Univ King Fahd Pet & Minerals

Inventors

• Ehsan Muhammad Ali
• Rehman Abdul

Classifications

• C23C16/40

  Oxides · CPC title

• C25B11/091

  consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds · CPC title

• C25B11/081

  the element being a noble metal · CPC title

• C25B1/55

  Photoelectrolysis · CPC title

• C23C16/4486

  by producing an aerosol and subsequent evaporation of the droplets or particles · CPC title