Method for reducing carbon dioxide and device used therefor

Patent metadata

Field	Value
Publication number	US-10087533-B2
Application number	US-201514795572-A
Country	US
Kind code	B2
Filing date	Jul 9, 2015
Priority date	Aug 29, 2014
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A method for reducing carbon dioxide is provided. In the present method, used is an anode electrode comprises a stacked structure of a photoelectric conversion layer, a metal layer, and an In x Ga 1-x N layer (where 0<x≤1). The In x Ga 1-x N layer is of i-type or n-type. The metal layer is interposed between the photoelectric conversion layer and the In x Ga 1-x N layer. When irradiating the anode electrode with light, a first light part included in the light is absorbed by the In x Ga 1-x N layer and a second light part included in the light travels through the In x Ga 1-x N layer. The second light part is absorbed by the photoelectric conversion layer to generate electric power in the photoelectric conversion layer. The second light part has a longer wavelength than the first light part. The carbon dioxide contained in the first electrolyte solution is reduced on the cathode electrode.

First claim

The invention claimed is:

1. A method for reducing carbon dioxide, comprising:
(a) preparing a carbon dioxide reduction device comprising:
a cathode chamber storing a first electrolyte solution containing carbon dioxide;
an anode chamber storing a second electrolyte solution;
a proton exchange membrane interposed between the cathode chamber and the anode chamber;
a cathode electrode that is in contact with the first electrolyte solution and that comprises a metal or a metal compound on the surface thereof; and
an anode electrode that is in contact with the second electrolyte solution, wherein

the carbon dioxide reduction device does not comprise an external power supply;
the anode electrode comprises a stacked structure of a photoelectric conversion layer, a metal layer, and an In x Ga 1-x N layer (where 0<x≤1);
the In x Ga 1-x N layer is of i-type or n-type;
the metal layer is interposed between the photoelectric conversion layer and the In x Ga 1-x N layer;
the metal layer covers a part of the photoelectric conversion layer;
the photoelectric conversion layer comprises a first p-type semiconductor layer and a first n-type semiconductor layer;
the first p-type semiconductor layer is electrically connected to the In x Ga 1-x N layer; and
the first n-type semiconductor layer is electrically connected to the cathode electrode; and
(b) irradiating the anode electrode with light, wherein in the step (b),
a first light part included in the light is absorbed by the In x Ga 1-x N layer;
a second light part included in the light travels through the In x Ga 1-x N layer;
the second light part is absorbed by the photoelectric conversion layer to generate electric power in the photoelectric conversion layer;
the second light part has a longer wavelength than the first light part; and
the carbon dioxide contained in the first electrolyte solution is reduced on the cathode electrode.

2. The method according to claim 1 , wherein
the light has a wavelength not less than 290 nanometers and not more than 840 nanometers.

3. The method according to claim 2 , wherein
the light is sunlight.

4. The method according to claim 1 , wherein
the value of x is not more than 0.4.

5. The method according to claim 4 , wherein
the value of x is not less than 0.05.

6. The method according to claim 5 , wherein
the value of x is not more than 0.15.

7. The method according to claim 1 , wherein
the anode electrode further comprises an n-type GaN layer; and
the GaN layer is interposed between the In x Ga 1-x N layer and the metal layer.

8. The method according to claim 1 , wherein
the first p-type semiconductor layer is formed of at least one selected from the group consisting of Si, GaAs, GaP, and Ge; and
the first n-type semiconductor layer is formed of at least one selected from the group consisting of Si, GaAs, GaP, and Ge.

9. The method according to claim 1 , wherein
the photoelectric conversion layer further comprises a second p-type semiconductor layer and a second n-type semiconductor layer;
the first n-type semiconductor layer is interposed between the first p-type semiconductor layer and the second p-type semiconductor layer; and
the second p-type semiconductor layer is interposed between the first n-type semiconductor layer and the second n-type semiconductor layer.

10. The method according to claim 1 , wherein
the first p-type semiconductor layer and the first n-type semiconductor layer are formed of a different semiconductor from each other.

11. The method according to claim 1 , wherein
the stacked structure further comprises a NiO y particle or a NiO y layer (0<y≤1); and
the In x Ga 1-x N layer is interposed between the NiO y particle or the NiO y layer and the metal layer.

12. A carbon dioxide reduction device comprising:
a cathode chamber storing a first electrolyte solution containing carbon dioxide;
an anode chamber storing a second electrolyte solution;
a proton exchange membrane interposed between the cathode chamber and the anode chamber;
a cathode electrode that is in contact with the first electrolyte solution and that comprises a metal or a metal compound on the surface thereof; and
an anode electrode that is in contact with the second electrolyte solution, wherein
the carbon dioxide reduction device does not comprise an external power supply;
the anode electrode comprises a stacked structure of a photoelectric conversion layer, a metal layer, and an In x Ga 1-x N layer (where 0<x≤1);
the In x Ga 1-x N layer is of i-type or n-type;
the metal layer is interposed between the photoelectric conversion layer and the In x Ga 1-x N layer;
the metal layer covers a part of the photoelectric conversion layer;
the photoelectric conversion layer comprises a first p-type semiconductor layer and a first n-type semiconductor layer;
the first p-type semiconductor layer is electrically connected to the In x Ga 1-x N layer; and
the first n-type semiconductor layer is electrically connected to the cathode electrode.

13. A method for reducing carbon dioxide, comprising:
(a) preparing a carbon dioxide reduction device comprising:
a cathode chamber storing a first electrolyte solution containing carbon dioxide;
an anode chamber storing a second electrolyte solution;
a proton exchange membrane interposed between the cathode chamber and the anode chamber;
a cathode electrode that is in contact with the first electrolyte solution and that comprises a metal or a metal compound on the surface thereof; and
an anode electrode that is in contact with the second electrolyte solution, wherein

the carbon dioxide reduction device does not comprise an external power supply;
the anode electrode comprises a stacked structure of a photoelectric conversion layer, a transparent electrode layer, and an In x Ga 1-x N layer (where 0<x≤1);
the In x Ga 1-x N layer is of i-type or n-type;
the transparent electrode layer is interposed between the photoelectric conversion layer and the In x Ga 1-x N layer;
the photoelectric conversion layer comprises a first p-type semiconductor layer and a first n-type semiconductor layer;
the first p-type semiconductor layer is electrically connected to the In x Ga 1-x N layer; and
the first n-type semiconductor layer is electrically connected to the cathode electrode; and
(b) irradiating the anode electrode with light, wherein in the step (b),
a first light part included in the light is absorbed by the In x Ga 1-x N layer;
a second light part included in the light travels through the In x Ga 1-x N layer;
the second light part is absorbed by the photoelectric conversion layer to generate electric power in the photoelectric conversion layer;
the second light part has a longer wavelength than the first light part; and
the carbon dioxide contained in the first electrolyte solution is reduced on the cathode electrode.

14. The method according to claim 13 , wherein
the light has a wavelength not less than 290 nanometers and not more than 840 nanometers.

15. The method according to claim 14 , wherein
the light is sunlight.

16. The method according to claim 13 , wherein
the value of x is not more than 0.4.

17. The method according to claim 16 , wherein
the value of x is not less than 0.05.

18. The method according to claim 17 , wherein
the value of x is not more than 0.15.

19. The method according to claim 13 , wherein
the anode electrode further comprises an n-type GaN layer; and
the GaN layer is interposed between the In x Ga 1-x

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Sekimoto Takeyuki
• Deguchi Masahiro
• Yotsuhashi Satoshi
• Hashiba Hiroshi
• Yamada Yuka
• Shinagawa Shuichi

Classifications

• B01J19/127

  Sunlight; Visible light · CPC title

• C25B3/04 Primary

  Chemistry & Metallurgy · mapped topic

• B01J19/128

  Infrared light · CPC title

• B01J19/123

  Ultraviolet light · CPC title

• C25B9/08

  Chemistry & Metallurgy · mapped topic