Catalyst and method of use thereof

Patent metadata

Field	Value
Publication number	US-11965255-B2
Application number	US-201916973890-A
Country	US
Kind code	B2
Filing date	Jun 12, 2019
Priority date	Jun 12, 2018
Publication date	Apr 23, 2024
Grant date	Apr 23, 2024

Abstract

This composite comprises: a material having electrical conductivity; and a transition metal oxide which is supported by said material. The transition metal oxide has an amorphous structure.

First claim

What is claimed is:

1. A composite comprising:
an electrically conductive material; and
an oxide of a transition metal supported on the electrically conductive material,
wherein the transition metal is at least one of transition metals of Group 8 to Group 10 in a periodic table,
wherein the oxide of the transition metal has an amorphous structure, wherein the oxide of the transition metal is a particle having an average particle size of 100 nm or less determined from a transmission electron microscope (TEM) image,
wherein in the oxide of the transition metal, an oxidation number of the transition metal changes flexibly and reversibly in response to an applied voltage, and
wherein the oxidation number of the transition metal changes when a voltage is applied to the composite, and the oxidation number further changes when the application of voltage is released.

2. An electrode catalyst in which the composite according to claim 1 is held on an electrically conductive base material,
wherein said electrically conductive base material is a porous material.

3. A membrane electrode assembly comprising:
an anode including a structure in which the composite according to claim 1 is held on an electrically conductive base material;
a cathode; and
an electrolyte membrane provided between said anode and said cathode,
wherein said electrically conductive base material is a porous material.

4. An alcohol synthesizer comprising the membrane electrode assembly according to claim 3 , and
including a first supply means for supplying water or water vapor to said anode,
a second supply means for providing carboxylic acids to said cathode, and
a means for recovering an alcohol produced at said cathode.

5. A method for producing the electrode catalyst according to claim 2 ,
the method comprising a step of immersing an electrically conductive material in a solution of a precursor of an oxide of a transition metal, and heating said solution in which said material is immersed.

6. A method for producing the electrode catalyst according to claim 2 ,
the method comprising a step of applying a transition metal obtained from a transition metal obtained by treating a precursor of an oxide of a transition metal with an aqueous solution of an alkali metal or an aqueous polyhydric alcohol to a solid electrolyte membrane, and joining together a base material holding an electrically conductive material.

7. The method for producing the electrode catalyst according to claim 5 ,
wherein said electrically conductive material is titanium oxide,
said oxide of the transition metal is iridium oxide, and
said electrically conductive base material is titanium.

8. A method for activating an electrode catalyst,
the method comprising a step of sweeping an applied voltage for one or more cycles in a range of −3.0 V to 1.5 V with respect to an onset potential, in a system of the electrode catalyst according to claim 2 and a standard electrode provided in an electrolytic solution.

9. The composite according to claim 1 , wherein the electrically conductive material and the oxide of the transition metal are bridged through oxygen.

10. The composite according to claim 1 , wherein a hydroxyl group is present on the oxide of the transition metal.

11. The composite according to claim 1 , wherein the oxide of the transition metal contains a lattice defect.

12. The composite according to claim 1 , wherein the electrically conductive material is at least one selected from the group consisting of carbon-based material and metal compound.

13. The composite according to claim 1 , wherein the electrically conductive material is at least one selected from the group consisting of a carbon-based material, a metal of Ni, V, Co, Mo, Fe, Cu, Zn, Sn, W, or Zr, an oxide of Ni, V, Co, Mo, Fe, Cu, Zn, Sn, W, or Zr, a carbide of Ni, V, Ti, Co, Mo, Fe, Cu, Zn, Sn, W, or Zr, a nitride of Ni, V, Ti, Co, Mo, Fe, Cu, Zn, Sn, W, or Zr, and TiO 2 .

14. The composite according to claim 13 , wherein the electrically conductive material is TiO 2 , and TiO 2 has a crystal structure of anatase type.

15. A composite comprising:
an electrically conductive material; and
an oxide of a transition metal supported on the electrically conductive material,
wherein the transition metal is at least one of transition metals of Group 8 to Group 10 in a periodic table,
wherein the oxide of the transition metal has an amorphous structure,
wherein the oxide of the transition metal is a particle having an average particle size of 100 nm or less determined from a transmission electron microscope (TEM) image, and
wherein the electrically conductive material is TiO 2 , and TiO 2 has a crystal structure of anatase type.

16. The composite according to claim 15 , wherein the electrically conductive material and the oxide of the transition metal are bridged through oxygen.

17. The composite according to claim 15 , wherein a hydroxyl group is present on the oxide of the transition metal.

18. The composite according to claim 15 , wherein the oxide of the transition metal contains a lattice defect.

Assignees

• Japan Science & Tech Agency

Inventors

• Yamauchi Miho
• Nakashima Naotoshi
• Kitano Sho
• Cheng Junfang
• Fukushima Takashi
• Higashi Manabu

Classifications

• C25B11/031

  Porous electrodes · CPC title

• C25B9/23

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

• C25B11/093 Primary

  at least one noble metal or noble metal oxide and at least one non-noble metal oxide · CPC title

• C25B11/052 Primary

  Electrodes comprising one or more electrocatalytic coatings on a substrate · CPC title

• C25B3/07

  Oxygen containing compounds · CPC title