Nanoporous thin film and method for fabricating the same

• US 9,925,530 B2
• Filed: 08/27/2015
• Issued: 03/27/2018
• Est. Priority Date: 09/05/2014
• Status: Active Grant

• Current Assignee: National Tsing Hua University
• Original Assignee: National Tsing Hua University
• Inventors: Perng, Tsong-Pyng, Chen, Hsueh-Shih, Su, Chung-Yi, Chen, Po-Hsun
• Primary Examiner(s): YOUNG, NATASHA E
• Application Number:
  US14/837,264
• Publication Number:
  US 20160067697A1
• Time in Patent Office: 943 Days
• CPC Class Codes: B01J 19/0093 Microreactors, e.g. miniaturised or microfabricated reactors laboratory containers with capillary fluid transport in microfabricated channels or chambers B01L3/5027
• CPC Class Codes: B01J 2219/00783 Laminate assemblies, i.e. the reactor comprising a stack of plates
• CPC Class Codes: B01J 2219/00792 One or more tube-shaped elements
• CPC Class Codes: B01J 2219/00822 Metal
• CPC Class Codes: B01J 2219/00824 Ceramic
• CPC Class Codes: B01J 2219/00835 Comprising catalytically active material
• CPC Class Codes: B01J 2219/00864 Channel sizes in the nanometer range, e.g. nanoreactors
• CPC Class Codes: B01J 2219/00869 Microreactors placed in parallel, on the same or on different supports
• CPC Class Codes: B01J 2219/00943 Visible light, e.g. sunlight
• CPC Class Codes: B01J 23/42 Platinum
• CPC Class Codes: B01J 35/23 in a colloidal state
• CPC Class Codes: B01J 35/39 Photocatalytic properties
• CPC Class Codes: B01J 35/393 Metal or metal oxide crystallite size
• CPC Class Codes: B01J 35/40 characterised by dimensions, e.g. grain size in a colloidal state B01J35/23; crystallite size B01J35/77
• CPC Class Codes: B01J 35/56 Foraminous structures having flow-through passages or channels, e.g. grids or three-dimensional monoliths
• CPC Class Codes: B01J 35/59 Membranes
• CPC Class Codes: B01J 37/0238 via the gaseous phase-sublimation
• CPC Class Codes: B01J 37/0244 Coatings comprising several layers
• CPC Class Codes: C02F 1/32 with ultraviolet light
• CPC Class Codes: C02F 1/725 by catalytic oxidation
• CPC Class Codes: C02F 2101/30 : Organic compounds
• CPC Class Codes: C02F 2305/10 : Photocatalysts

Abstract

The present invention relates to a nanoporous thin film and a method for fabricating the same. The nanoporous thin film fabricating method for fabricating a nanoporous thin film with a composite photocatalyst structure for a photodegradation and a water purification includes providing a porous substrate with a plurality of through-nanopores therein, each of which through-nanopores have an inner tube wall; forming an oxide-based photocatalyst layer over the porous substrate and the inner tube wall by using a first chemical-based deposition process; and forming a metal-based photocatalyst layer on a part of the oxide-based photocatalyst layer by using a second chemical-based deposition process.

Claims

1. A nanoporous thin film fabricating method for fabricating a nanoporous thin film with a composite photocatalyst structure for a photodegradation and a water purification, comprising:

providing a porous substrate with a plurality of through-nanopores therein, each of which through-nanopores have an inner tube wall;

forming a metal-oxide-based photocatalyst layer consisting of one single sort of a metal oxide material over the porous substrate and the inner tube wall conformably by using a horizontal flow-type atomic layer deposition process;

forming a metal-based photocatalyst layer consisting of one single sort of a metal material, which the metal material is one selected from a group consisting of a Pt, an Au, a Cu, and a Ni, partly on a part of the metal-oxide-based photocatalyst layer by using a vertical flow-type atomic layer deposition process; and

transforming the metal-oxide-based photocatalyst layer into an anatase phase.

2. The method according to claim 1 further comprising:

removing an excessive overlay of the metal-oxide-based photocatalyst layer by using one of a mechanical polishing scheme and a chemical mechanical polishing scheme; and

transforming the metal-oxide-based photocatalyst layer into an anatase phase by an annealing scheme.

3. The method according to claim 1, wherein the first chemical-based deposition process is one selected from a group consisting of an atomic layer deposition (ALD) process, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process and a combination thereof and the second chemical-based deposition process is one selected from a group consisting of an atomic layer deposition (ALD) process, a chemical vapor deposition (CVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process and a combination thereof.

4. The method according to claim 3, wherein the first chemical-based deposition process and the second chemical-based deposition process are the same chemical-based deposition process and the first chemical-based deposition process and the second chemical-based deposition process are the ALD process.

5. The method according to claim 1, wherein the metal oxide material is one selected from a group consisting of a TiO₂, a ZnO, a SnO₂, and a TiO_XN_2-X.

6. A nanoporous thin film having a composite photocatalyst structure for a photodegradation and a water purification and manufactured by using a chemical-based deposition process, comprising:

a porous substrate with an array of through-nanopores therein, each of which through-nanopores have an inner tube wall;

a metal-oxide-based photocatalyst layer consisting of one single sort of metal oxide material formed over the porous substrate and the inner tube wall conformably by a horizontal flow-type atomic layer deposition process, wherein the metal-oxide-based photocatalyst layer is in an anatase phase; and

a metal-based photocatalyst layer consisting of one single sort of a metal material, which the metal material is one selected from a group consisting of a Pt, an Au, a Cu, and a Ni, formed on a part of the metal-oxide-based photocatalyst layer by a vertical flow-type atomic layer deposition process, wherein the nanoporous thin film acts as a nanoreactor and is applied to a nanoreactor unit, and the nanoreactor unit comprises;

a first base having a first conduit for guiding a reactant fluid flowing therethrough;

a second base having a second conduit for guiding the reactant fluid flowing therethrough, wherein one of the first and second bases is made of a light transmissible material; and

the nanoporous thin film acting as the nanoreactor sandwiched between the first base and the second base, wherein the reactant fluid flows through the nanoreactor unit via the first conduit, the nanoporous thin film and the second conduit.

7. The nanoporous thin film according to claim 6, wherein the composite photocatalyst structure comprises the metal-oxide-based photocatalyst layer and the metal-based photocatalyst layer.

8. The nanoporous thin film according to claim 6, wherein the metal-based photocatalyst layer includes a plurality of metal photocatalyst particles, each of which particles have a particle diameter in a range between 0.5 nm˜

100 nm.

9. The nanoporous thin film according to claim 6, wherein each of the through-nanopores have a tube with the inner tube wall therein and the tube has a tube diameter in a range between 11 nm˜

200 nm and a tube length in a range between 0.001 cm˜

10 cm.

10. The nanoporous thin film according to claim 6, wherein the nanoreactor unit further comprises:

a spacer sheet having a center part and an open hole disposed at the center part, in which the nanoreactor is placed on the spacer sheet and situated correspondingly at the center part.

11. The nanoporous thin film according to claim 6, wherein there are multiple nanoreactor units arranged in a configuration selected from a group consisting of a serial configuration, a parallel configuration, a hybrid configuration of the serial and parallel configurations, an array configuration and a combination thereof.

12. The nanoporous thin film according to claim 6, wherein there are multiple nanoreactors arranged in a configuration selected from a group consisting of a serial configuration, a parallel configuration, a hybrid configuration of the serial and parallel configurations, an array configuration and a combination thereof.

13. The nanoporous thin film according to claim 6, wherein the nanoreactor unit is included in a nanoreactor system and the nanoreactor system comprises:

a reservoir connected with the first conduit and used for storing the reactant fluid; and

a pump connected with the second conduit and used for providing a suction force to the reactant fluid so as to drive it to flow through the nanoreactor.

14. The nanoporous thin film according to claim 13, wherein the nanoreactor system further comprises the plurality of the nanoreactor units.

15. The nanoporous thin film according to claim 6, wherein the nanoreactor has an ability to photodegrade 27.7% of a contaminant off within 2.7×

10<sup>−

2</sup> second.