NANOPARTICLES CONTAINING TITANIUM OXIDE

• US 20070202334A1
• Filed: 12/22/2006
• Published: 08/30/2007
• Est. Priority Date: 12/29/2005
• Status: Active Grant

• Current Assignee: Board of Trustees of The University of Illinois
• Original Assignee: Board of Trustees of The University of Illinois
• Inventors: Shang, Jian-Ku, Wu, Pinggui, Xie, Rong-Cai
• Granted Patent: US 7,521,394 B2
• Time in Patent Office: Days
• US Class Current: 428/402
• CPC Class Codes: B01J 21/063 Titanium; Oxides or hydroxides thereof
• CPC Class Codes: B01J 23/40 of the platinum group metals
• CPC Class Codes: B01J 23/74 Iron group metals
• CPC Class Codes: B01J 35/0013 Colloids
• CPC Class Codes: B01J 35/004 Photocatalysts
• CPC Class Codes: B01J 35/23 in a colloidal state
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 35/45 Nanoparticles
• CPC Class Codes: B01J 37/0215 Coating
• CPC Class Codes: B01J 37/036 to form a gel or a cogel
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: C01G 23/047 Titanium dioxide
• CPC Class Codes: C01G 23/053 Producing by wet processes, e.g. hydrolysing titanium salts
• CPC Class Codes: C01P 2002/52 containing elements as dopants
• CPC Class Codes: C01P 2002/72 by d-values or two theta-values, e.g. as X-ray diagram
• CPC Class Codes: C01P 2004/04 obtained by TEM, STEM, STM or AFM
• CPC Class Codes: C01P 2004/10 extending in one dimension, e.g. needle-like
• CPC Class Codes: C01P 2004/16 Nanowires or nanorods, i.e. solid nanofibres with two nearly equal dimensions between 1-100 nanometer
• CPC Class Codes: C01P 2004/22 with a polygonal circumferential shape
• CPC Class Codes: C01P 2004/39 parallelepiped-like
• CPC Class Codes: C01P 2004/40 : prism-like
• CPC Class Codes: C01P 2004/62 : Submicrometer sized, i.e. from 0.1-1 micrometer
• CPC Class Codes: C01P 2004/64 : Nanometer sized, i.e. from 1-100 nanometer
• CPC Class Codes: C04B 2235/3232 : Titanium oxides or titanates, e.g. rutile or anatase
• CPC Class Codes: C04B 2235/3289 : Noble metal oxides
• CPC Class Codes: C04B 2235/3291 : Silver oxides
• CPC Class Codes: C04B 35/62259 : Fibres based on titanium oxide
• CPC Class Codes: Y10S 977/70 : Nanostructure
• CPC Class Codes: Y10S 977/762 : Nanowire or quantum wire, i.e. axially elongated structure having two dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/773 : Nanoparticle, i.e. structure having three dimensions of 100 nm or less
• CPC Class Codes: Y10S 977/811 : Of specified metal oxide composition, e.g. conducting or semiconducting compositions such as ITO, ZnOx
• CPC Class Codes: Y10T 428/2982 : Particulate matter [e.g., sphere, flake, etc.]

Abstract

A titanium oxide nanoparticle includes anatase titanium oxide, and may be a nanofiber having a minimum dimension less than 200 nanometers and having an aspect ratio greater than 20:1. A titanium oxide nanoparticle including anatase titanium oxide may include a dopant metal and/or a dopant nonmetal, and may be in a form other than a nanosphere. A method of making nanoparticles includes heating a reaction mixture in an autoclave, where the reaction mixture includes a titanium source and a polar organic solvent.

Claims

1. A nanofiber, comprising:

anatase titanium oxide,

where the nanofiber has a longest dimension greater than 200 nanometers, and an aspect ratio greater than 20;

1.

2. The nanofiber of claim 1, having a diameter of at most 5 nanometers.

3. The nanofiber of claim 1, having a diameter of from 0.5 nanometer to 3 nanometers.

4. The nanofiber of claim 1, where the nanofiber is a nanowire having a longest dimension of at least 1,000 nanometers.

5. The nanofiber of claim 4, having a diameter of at most 25 nanometers.

6. The nanofiber of claim 4, having a longest dimension of at least 2 micrometers.

7. The nanofiber of claim 4, having a longest dimension of at least 5 micrometers.

8. The nanofiber of claim 1, where the nanofiber is a nanobelt having a thickness of at most 10 nanometers.

9. The nanofiber of claim 8, where the nanofiber is a nanosheet having a width greater than 200 nanometers.

10. The nanofiber of claim 1, further comprising at least one element selected from the group consisting of a dopant metal and a dopant nonmetal.

11. The nanofiber of claim 10, comprising a dopant metal selected from the group consisting of calcium, cobalt, nickel, copper, gallium, strontium, yttrium, zirconium, palladium, silver, tin, lanthanum and platinum.

12. The nanofiber of claim 11, comprising a dopant nonmetal selected from the group consisting of boron, carbon, nitrogen, sulfur and fluorine.

13. The nanofiber of claim 10, comprising a dopant nonmetal selected from the group consisting of boron, carbon, nitrogen, sulfur and fluorine.

14. A nanoparticle, comprising:

anatase titanium oxide, and

at least one element selected from the group consisting of a dopant metal and a dopant nonmetal;

where the nanoparticle is not a nanosphere.

15. The nanoparticle of claim 14, where the nanoparticle is in a form selected from the group consisting of a nanorod, a nanofiber, a nanowire, a nanobelt, a nanosheet, a nanoprism, and a nanonetwork.

16-26. -26. (canceled)

27. A catalytic composition, comprising:

nanoparticles comprising anatase titanium oxide;

where, when an organic substance is in contact with the composition and is irradiated with visible light, the concentration of the organic substance is reduced by 40% within 4 hours.

28-29. -29. (canceled)

30. A catalytic composition, comprising:

nanoparticles comprising anatase titanium oxide;

where, when bacteria are in contact with the composition and are irradiated with visible light, the concentration of living bacteria is reduced by 20% within 20 hours.

31-32. -32. (canceled)

33. A method of making nanoparticles, comprising:

heating a reaction mixture in an autoclave at a temperature of 170°

C. to 300°

C. for at least 5 hours to form nanoparticles;

where the reaction mixture comprises a titanium source and a polar organic solvent.

34-47. -47. (canceled)

48. A method of making nanoparticles, comprising:

combining ingredients to form a reaction mixture, the ingredients comprising

a titanium source,

a polar organic solvent, and

at least one of a dopant nonmetal source and a dopant metal salt; and

heating the reaction mixture in an autoclave at a temperature of 170°

C. to 300°

C. for at least 5 hours.

49. A method of making nanoparticles, comprising:

combining ingredients to form a reaction mixture, the ingredients comprising

a titanium source,

a polar organic solvent,

a dopant nonmetal source, and

a dopant metal salt; and

heating the reaction mixture in an autoclave at a temperature of 170°

C. to 300°

C. for at least 5 hours.