Titanium substrate, method for producing titanium substrate, electrode for water electrolysis, and water electrolysis apparatus

Patent metadata

Field	Value
Publication number	US-2023143743-A1
Application number	US-202117912960-A
Country	US
Kind code	A1
Filing date	Mar 25, 2021
Priority date	Mar 26, 2020
Publication date	May 11, 2023
Grant date	—

Abstract

A titanium substrate of the present invention includes a substrate main body formed of titanium or a titanium alloy, in which a Magneli phase titanium oxide film formed of a Magneli phase titanium oxide represented by a chemical formula Ti n O 2n-1 (4≤n≤10) is formed on a surface of the substrate main body and a BET value of the substrate main body on which the Magneli phase titanium oxide film is formed is 0.1 m 2 /g or less.

First claim

1 . A titanium substrate comprising:
a substrate main body formed of titanium or a titanium alloy, wherein a Magneli phase titanium oxide film is formed on a surface of the substrate main body, the Magneli phase titanium oxide film is formed of a Magneli phase titanium oxide represented by a chemical formula Ti n O 2n-1 (4≤n≤10), and a BET value of the substrate main body on which the Magneli phase titanium oxide film is formed is 0.1 m 2 /g or less.

2 . The titanium substrate according to claim 1 ,
wherein the Magneli phase titanium oxide film contains at least one of Ti 4 O 7 and Ti 5 O 9 .

3 . The titanium substrate according to claim 1 ,
wherein the Magneli phase titanium oxide film has a film thickness in a range of 0.01 μm or more and 3.0 μm or less.

4 . The titanium substrate according to claim 1 ,
wherein the substrate main body is a porous body having a porosity in a range of 30% or more and 97% or less.

5 . A method for producing a titanium substrate, in which the titanium substrate according to claim 1 is produced, the method comprising:
a TiO 2 film forming step of forming a TiO 2 film on a surface of a substrate main body formed of titanium or a titanium alloy; and
a reduction treatment step of reducing the TiO 2 film formed on the surface of the substrate main body by using a microwave plasma reduction method to obtain a Magneli phase titanium oxide film, the Magneli phase titanium oxide film being formed of a Magneli phase titanium oxide represented by a chemical formula Ti n O 2n-1 (4≤n≤10).

6 . An electrode for water electrolysis, comprising:
the titanium substrate according to claim 1 .

7 . The electrode for water electrolysis according to claim 6 ,
wherein, in a voltammetry test in which one cycle is denoted by a step of holding for 1 minute at 2.5 V and a step of holding for 1 minute at 0 V, an energy efficiency after 10 cycles is 90% or more of an initial value.

8 . A solid polymer-type water electrolysis apparatus comprising: the electrode for water electrolysis according to claim 6 .

Assignees

• Mitsubishi Materials Corp

Inventors

• Sano Yosuke
• Ohmori Shinichi

Classifications

• C25B11/031

  Porous electrodes · CPC title

• C25B9/23

  comprising ion-exchange membranes in or on which electrode material is embedded · CPC title

• C25B11/063 Primary

  Valve metal, e.g. titanium · CPC title

• C25B11/02

  characterised by shape or form · CPC title

• C25B1/04 Primary

  by electrolysis of water · CPC title