Corrosion resistant and electrically conductive surface of metal

• US 9,493,883 B2
• Filed: 05/15/2015
• Issued: 11/15/2016
• Est. Priority Date: 02/23/2012
• Status: Active Grant

• Current Assignee: Treadstone Technologies, Inc.
• Original Assignee: Treadstone Technologies, Inc.
• Inventors: Wang, Conghua
• Primary Examiner(s): Ryan, Patrick
• Assistant Examiner(s): MCCONNELL, WYATT P
• Application Number:
  US14/713,348
• Publication Number:
  US 20150247247A1
• Time in Patent Office: 550 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: C23C 16/513 using plasma jets
• CPC Class Codes: C23C 28/321 with at least one metal alloy layer
• CPC Class Codes: C23C 28/3455 with a refractory ceramic layer, e.g. refractory metal oxide, ZrO2, rare earth oxides or a thermal barrier system comprising at least one refractory oxide layer
• CPC Class Codes: C23C 4/08 containing only metal elements C23C4/073 takes precedence
• CPC Class Codes: C23C 4/18 After-treatment
• CPC Class Codes: C23C 8/10 Oxidising
• CPC Class Codes: C25B 11/091 consisting of at least one catalytic element and at least one catalytic compound; consisting of two or more catalytic elements or catalytic compounds
• CPC Class Codes: C25B 13/04 characterised by the material
• CPC Class Codes: C25B 9/23 comprising ion-exchange membranes in or on which electrode material is embedded
• CPC Class Codes: C25D 11/022 Anodisation on selected surface areas
• CPC Class Codes: C25D 11/26 of refractory metals or alloys based thereon
• CPC Class Codes: H01M 4/02 Electrodes composed of, or comprising, active material
• CPC Class Codes: H01M 4/36 Selection of substances as active materials, active masses, active liquids
• CPC Class Codes: H01M 4/8647 consisting of more than one material, e.g. consisting of composites
• CPC Class Codes: H01M 8/0202 Collectors; Separators, e.g. bipolar separators; Interconnectors
• CPC Class Codes: H01M 8/0208 Alloys
• CPC Class Codes: H01M 8/0228 in the form of layered or coated products
• CPC Class Codes: H01M 8/0245 in the form of layered or coated products
• CPC Class Codes: H01M 8/188 by recharging of redox couples containing fluids; Redox flow type batteries
• CPC Class Codes: H01M 8/20 Indirect fuel cells, e.g. fuel cells with redox couple being irreversible H01M8/18 takes precedence
• CPC Class Codes: Y02E 60/10 : Energy storage using batteries
• CPC Class Codes: Y02E 60/50 : Fuel cells

Abstract

Methods for coating a metal substrate or a metal alloy with electrically conductive titania-based material. The methods produce metal components for electrochemical devices that need high electrical conductance, corrosion resistance and electrode reaction activities for long term operation at a low cost.

Claims

1. A method of coating a surface of a metal substrate, said method comprising:

providing the metal substrate;

depositing a titanium alloy on the surface of the metal substrate; and

heat treating the deposited titanium alloy on the surface of the metal substrate to grow a doped titania material on an outer surface of the titanium alloy to form a conductive surface layer and maintain a layer of the titanium alloy between the doped titania conductive surface layer and the metal substrate,

wherein the titanium alloy contains elements having a valence greater than +4.

2. The method of claim 1, wherein the elements having a valence greater than +4 comprise at least one of niobium, vanadium, arsenic, selenium, antimony, molybdenum or tungsten, and a concentration of the elements having a valence greater than +4 are in the range of 1%-30%.

3. The method of claim 1, wherein the doped titania material is grown using a thermal oxidation process.

4. The method of claim 1, wherein the doped titania material is grown using a plasma oxidization.

5. The method of claim 1, further comprising an interface layer on the metal substrate.

6. An electrochemical device comprising:

a metal component having a first surface; and

an electrically conductive doped titanium oxide surface coating layer being bonded to the first surface of the metal component by a titanium alloy layer,

wherein the doped titanium oxide surface layer and the titanium alloy layer contain same elements having a valence greater than +4.

7. The device of claim 6, wherein the elements having a valence greater than +4 comprise at least one of niobium, vanadium, arsenic, selenium, antimony, molybdenum or tungsten, and a concentration of the elements having a valence greater than +4 are in the range of 1-30%.

8. The device of claim 6, wherein the device is an electrolyzer cell and the metal component is separator plate or gas diffusion layer.

9. The device of claim 6, wherein the device is a lead acid flow battery and the component is an electrode of the battery.

10. The device of claim 6, wherein the device is a flow battery and the metal component is a separator plate or an electrode of the battery.

11. The device of claim 6, wherein the device is a proton exchange membrane fuel cell and the metal component is a separator plate of the fuel cell.

12. The device of claim 6, further comprising an interface layer on the metal component.

13. A plate for a fuel cell, said plate comprising:

a metal substrate having a first surface;

an interface layer on the first surface of the substrate, said interface layer comprising a titanium alloy; and

an electrically conductive doped titanium oxide surface layer comprising a doped titania material and being bonded to the first surface of the metal substrate by the titanium alloy interface layer,

wherein the titanium alloy contains a same element as the dopant in the doped titania material and the same element has a valence greater than +4.

14. The plate of claim 13, wherein said titanium alloy comprises at niobium.

15. The plate of claim 13, wherein the titanium has a thickness of approximately 0.1 nm to 100 μ

m.

16. The plate of claim 13, wherein the titanium alloy has a thickness of approximately 0.01 μ

m to 10 μ

m.

17. The plate of claim 13, wherein the titanium alloy has a thickness of approximately 0.5 μ

m to 5 μ

m.