Self-cleaning coatings applied to solar thermal devices

• US 20070134501A1
• Filed: 10/10/2006
• Published: 06/14/2007
• Est. Priority Date: 12/13/2005
• Status: Abandoned Application

• Current Assignee: Innovative Thin Films, Ltd., University of Toledo
• Original Assignee: Innovative Thin Films, Ltd., University of Toledo
• Inventors: McMaster, Alan, Giolando, Dean
• Application Number:
  US11/545,298
• Publication Number:
  US 20070134501A1
• Time in Patent Office: Days
• US Class Current: 428/432
• CPC Class Codes: C03C 17/007 containing a dispersed phase, e.g. particles, fibres or flakes, in a continuous phase
• CPC Class Codes: C03C 2217/475 Inorganic materials
• CPC Class Codes: C03C 2217/477 Titanium oxide
• CPC Class Codes: C03C 2217/71 Photocatalytic coatings
• CPC Class Codes: C03C 2218/113 by sol-gel processes
• CPC Class Codes: C23C 18/1216 Metal oxides C23C18/1212 takes precedence
• CPC Class Codes: C23C 18/127 Preformed particles
• CPC Class Codes: F24S 40/40 Preventing corrosion; Protecting against dirt or contamination
• CPC Class Codes: F24S 70/30 Auxiliary coatings, e.g. anti-reflective coatings
• CPC Class Codes: F24S 80/52 characterised by the material for preventing heat loss F24S80/56
• CPC Class Codes: F24S 80/56 characterised by means for preventing heat loss
• CPC Class Codes: F28F 2245/08 self-cleaning
• CPC Class Codes: Y02E 10/40 Solar thermal energy, e.g. solar towers

Abstract

A process for preparing a self-cleaning coating on a substrate such as glass comprises providing a coating composition, adding to the coating composition nanocrystals of a photoactive material, and applying the mixture of coating composition and photoactive material to a surface of a substrate at an elevated temperature, to deposit a self-cleaning coating on the surface of the substrate. A solar thermal device comprises a solar energy conversion device, including a transparent substrate, and a self-cleaning coating adhered to a surface of the substrate.

Claims

1. A process for preparing a self-cleaning coated substrate, comprising the steps of:

providing a coating composition;

adding to the coating composition nanocrystals of a photoactive material; and

applying the mixture of coating composition and photoactive material to a surface of a substrate at an elevated temperature, to deposit a self-cleaning coating on the surface of the substrate.

2. The process for preparing a self-cleaning coated substrate according to claim 1, wherein the coating composition comprises at least one of Al(OPr)₃, Ti(OPr)₄, Zr(OPr)₄, Si(OEt)₄, Sn(OBu)₄, SnCl4, SnBu₂O/acetate, Fe(OEt)₂, Mg(OEt)₂, or CaO.

3. The process for preparing a self-cleaning coated substrate according to claim 1, wherein the photoactive material comprises at least one of T₁O₂, WO₃, Fe₂O₃, and CuO.

4. The process for preparing a self-cleaning coated substrate according to claim 1, wherein the temperature ranges from about 80°

C. to about 700°

C.

5. The process for preparing a self-cleaning coated substrate according to claim 1, wherein the substrate comprises at least one of glass, ceramic, metal, or plastic.

7. A self-cleaning coated substrate prepared by the process of claim 1.

17. The solar thermal device according to claim 9, including a self-cleaning coating prepared by the process of claim 1.

19. A renewable energy conversion device, including a self-cleaning coating prepared by the process of claim 1.

6. A process for preparing a self-cleaning coated substrate, comprising the steps of:

providing a coating composition, comprising at least one of Al(OPr)₃, Ti(OPr)₄, Zr(OPr)₄, Si(OEt)₄, Sn(OBu)₄, SnCl₄, SnBu₂O/acetate, Fe(OEt)₂, Mg(OEt)₂, or CaO;

adding to the coating composition nanocrystals of a photoactive material, comprising at least one of T₁O₂, WO₃, Fe₂O₃, and CuO.

applying the mixture of coating composition and photoactive material to a surface of a substrate, comprising at least one of glass, ceramic, metal, or plastic, at an elevated temperature form about 80°

C. to about 700°

C., to deposit a self-cleaning coating on the surface of the substrate.

8. A self-cleaning coated substrate prepared by the process of claim 6.

18. The solar thermal device according to claim 9, including a self-cleaning coating prepared by the process of claim 6.

20. A renewable energy conversion device, including a self-cleaning coating prepared by the process of claim 6.

9. A solar thermal device, comprising:

a solar energy conversion device, including a transparent substrate; and

a self-cleaning coating adhered to at least a portion of a surface of the substrate.

10. The solar thermal device according to claim 9, wherein the solar energy conversion device is one of a solar energy collector for heating a fluid or a solar energy collector for generating electricity.

11. The solar thermal device according to claim 10, wherein the solar energy collector includes a reflector.

12. The solar thermal device according to claim 9, wherein the transparent substrate comprises at least one of glass, ceramic, or plastic.

13. The solar thermal device according to claim 12, wherein the transparent substrate comprises glass.

14. The solar thermal device according to claim 9, wherein the self-cleaning coating comprises at least one of an oxide of aluminum, titanium, zirconium, silicon, tin, iron, magnesium, calcium, or tungsten.

15. The solar thermal device according to claim 9, wherein the self-cleaning coating comprises nanocrystals of a photoactive material.

16. The solar thermal device according to claim 15, wherein the photoactive material comprises at least one of T₁O₂, WO₃, Fe₂O₃, and CuO.