Techniques for photocatalytic hydrogen generation

Patent metadata

Field	Value
Publication number	US-9790602-B2
Application number	US-201414456708-A
Country	US
Kind code	B2
Filing date	Aug 11, 2014
Priority date	Aug 11, 2014
Publication date	Oct 17, 2017
Grant date	Oct 17, 2017

Abstract

Techniques for photocatalytic hydrogen generation are provided. In one aspect, a hydrogen producing cell is provided. The hydrogen producing cell includes an anode electrode; a photocatalytic material adjacent to the anode electrode; a solid electrolyte adjacent to a side of the photocatalytic material opposite the anode electrode; and a cathode electrode adjacent to a side of the solid electrolyte opposite the photocatalytic material. A solar hydrogen producing system including at least one solar concentrating assembly having the hydrogen producing cell, and a method for producing hydrogen using the hydrogen producing cell are also provided.

First claim

What is claimed is:

1. A hydrogen producing cell, comprising:
an anode electrode;
a photocatalytic material adjacent to the anode electrode;
a solid electrolyte adjacent to a side of the photocatalytic material opposite the anode electrode, wherein the solid electrolyte comprises multiple layers of varying density and porosity; and
a cathode electrode adjacent to a side of the solid electrolyte opposite the photocatalytic material, wherein the cathode electrode, the solid electrolyte, the photocatalytic material, and the anode electrode are configured as a stack of layers disposed one on top of another with the photocatalytic material separating the solid electrolyte from the anode electrode.

2. The hydrogen producing cell of claim 1 , wherein the photocatalytic material comprises titanium oxide, tin oxide, or tungsten trioxide.

3. The hydrogen producing cell of claim 1 , wherein the photocatalytic material is porous and permeable to gases.

4. The hydrogen producing cell of claim 1 , wherein the photocatalytic material is dense and impermeable to gases.

5. The hydrogen producing cell of claim 1 , wherein the solid electrolyte is formed from a proton-conducting electrolyte material selected from the group consisting of: yttrium-doped barium cerium zirconate (BCZY), barium zirconate, barium cerate, yttrium-doped barium zirconate, yttrium-doped barium cerate, and combinations comprising at least one of the foregoing materials, and wherein the solid electrolyte is dense and impermeable to gases.

6. The hydrogen producing cell of claim 1 , wherein the solid electrolyte comprises:
a first solid electrolyte layer adjacent to a side of the photocatalytic material opposite the anode electrode, wherein the first solid electrolyte layer is porous and permeable to gases;
a second solid electrolyte layer adjacent to a side of the first solid electrolyte layer opposite the photocatalytic material, wherein the second solid electrolyte layer is dense and impermeable to gases; and
a third solid electrolyte layer adjacent to a side of the second solid electrolyte layer opposite the first solid electrolyte layer, wherein the third solid electrolyte layer is porous and permeable to gases.

7. The hydrogen producing cell of claim 6 , wherein the first solid electrolyte layer, the second solid electrolyte layer, and the third solid electrolyte layer are each formed from a proton-conducting electrolyte material selected from the group consisting of: BCZY, barium zirconate, barium cerate, yttrium-doped barium zirconate, yttrium-doped barium cerate, and combinations comprising at least one of the foregoing materials.

8. The hydrogen producing cell of claim 1 , wherein the anode electrode is formed from a material selected from the group consisting of: doped indium oxide, doped tin oxide, conductive carbon nanotubes, conductive nanowires, and combinations comprising at least one of the foregoing materials.

9. The hydrogen producing cell of claim 1 , wherein at least one of the anode electrode and the cathode electrode is porous and permeable to gases.

10. The hydrogen producing cell of claim 1 , wherein at least one of the anode electrode and the cathode electrode is dense and impermeable to gases.

11. The hydrogen producing cell of claim 1 , wherein the cathode electrode is formed from at least one metal selected from the group consisting of: platinum, palladium, silver, ruthenium, nickel, and combinations comprising at least one of the foregoing metals.

12. The hydrogen producing cell of claim 1 , further comprising:
an external circuit comprising a voltage source connected to both the anode electrode and the cathode electrode.

13. A solar hydrogen producing system, comprising:
at least one solar concentrating assembly having i) a solar concentrator optic and ii) a hydrogen producing cell, wherein the hydrogen producing cell comprises an anode electrode, a photocatalytic material adjacent to the anode electrode, a solid electrolyte adjacent to a side of the photocatalytic material opposite the anode electrode, wherein the solid electrolyte comprises multiple layers of varying density and porosity, and a cathode electrode adjacent to a side of the solid electrolyte opposite the photocatalytic material, wherein the cathode electrode, the solid electrolyte, the photocatalytic material, and the anode electrode are configured as a stack of layers disposed one on top of another with the photocatalytic material separating the solid electrolyte from the anode electrode, and
wherein the solar concentrator optic is positioned relative to the hydrogen producing cell to direct incident sunlight onto the anode electrode of the hydrogen producing cell.

14. The solar hydrogen producing system of claim 13 , further comprising:
a casing enclosing the hydrogen producing cell.

15. The solar hydrogen producing system of claim 14 , wherein the casing comprises:
a water inlet for introducing water vapor into the hydrogen producing cell;
an oxygen exhaust for removing oxygen from the hydrogen producing cell; and
a hydrogen gas exhaust for collecting hydrogen gas from the hydrogen producing cell.

16. The solar hydrogen producing system of claim 13 , wherein the solid electrolyte comprises:
a first solid electrolyte layer adjacent to a side of the photocatalytic material opposite the anode electrode, wherein the first solid electrolyte layer is porous and permeable to gases;
a second solid electrolyte layer adjacent to a side of the first solid electrolyte layer opposite the photocatalytic material, wherein the second solid electrolyte layer is dense and impermeable to gases; and
a third solid electrolyte layer adjacent to a side of the second solid electrolyte layer opposite the first solid electrolyte layer, wherein the third solid electrolyte layer is porous and permeable to gases.

17. The solar hydrogen producing system of claim 16 , wherein the first solid electrolyte layer, the second solid electrolyte layer, and the third solid electrolyte layer are each formed from a proton-conducting electrolyte material selected from the group consisting of: BCZY, barium zirconate, barium cerate, yttrium-doped barium zirconate, yttrium-doped barium cerate, and combinations comprising at least one of the foregoing materials.

18. A method for producing hydrogen, the method comprising the steps of:
introducing water vapor to a hydrogen producing cell having an anode electrode, a photocatalytic material adjacent to the anode electrode, a solid electrolyte adjacent to a side of the photocatalytic material opposite the anode electrode, wherein the solid electrolyte comprises multiple layers of varying density and porosity, and a cathode electrode adjacent to a side of the solid electrolyte opposite the photocatalytic material, wherein the cathode electrode, the solid electrolyte, the photocatalytic material, and the anode electrode are configured as a stack of layers disposed one on top of another with the photocatalytic material separating the solid electrolyte from the anode electrode;
directing concentrated sunlight onto the hydrogen producing cell which provides a source of heat and visible radiation to operate the hydrogen producing cell such that electron-hole pairs are generated in the photocatalytic material and used to split the water vapor into hydrogen ions and oxygen gas;
applying a potential between the anode electrode and the cathode electrode of the hydrogen producing cell which, via a concentration gradient in the solid electrolyte, transports the hydrogen ions through the solid electrol

Assignees

• IBM

Inventors

• Gershon Talia S
• Guha Supratik
• Todorov Teodor K
• Van Kessel Theodore G

Classifications

• C25B9/08

  Chemistry & Metallurgy · mapped topic

• B01J2219/00891

  Feeding or evacuation · CPC title

• B01J2219/0875

  Gas · CPC title

• C25B1/003 Primary

  Chemistry & Metallurgy · mapped topic

• B01J2219/00943

  Visible light, e.g. sunlight · CPC title