Method for producing photocatalyst electrode for water decomposition

1. A method for producing a photocatalyst electrode for water decomposition, the method comprising:

a metal layer forming step of forming a metal layer on one surface of a first substrate by a vapor phase film-forming method or a liquid phase film-forming method;

a photocatalyst layer forming step of forming a photocatalyst layer by subjecting the metal layer to at least one treatment selected from an oxidation treatment, a nitriding treatment, a sulfurization treatment, or a selenization treatment;

a current collecting layer forming step of forming a current collecting layer on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate; and

a detachment step of detaching the first substrate from the photocatalyst layer.

2. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , wherein the photocatalyst layer forming step is a step of performing the oxidation treatment, and then performing at least one treatment selected from the nitriding treatment, the sulfurization treatment, and the selenization treatment.

3. The method for producing a photocatalyst electrode for water decomposition according to claim 2 , wherein the metal that constitutes the metal layer is at least one metal selected from the group consisting of Ta, Nb, Ti, W, Ba, La, Sr, Ca, Fe, Bi, V, Zn, Cu, Ni, Pb, Ag, Cd, Ga, In, Sm, and Mg.

4. The method for producing a photocatalyst electrode for water decomposition according to claim 2 , further comprising:

after the photocatalyst layer forming step and before the current collecting layer forming step, a contact layer forming step of forming a contact layer containing a semiconductor or a good conductor on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate.

5. The method for producing a photocatalyst electrode for water decomposition according to claim 2 , further comprising:

after the current collecting layer forming step and before the detachment step, a second substrate laminating step of laminating a second substrate on a surface of the current collecting layer, the surface being on the opposite side of the photocatalyst layer.

6. The method for producing a photocatalyst electrode for water decomposition according to claim 2 , wherein the photocatalyst layer has a thickness of 100 nm to 1,200 nm.

7. The method for producing a photocatalyst electrode for water decomposition according to claim 2 , wherein the first substrate is a silicon substrate.

8. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , wherein the metal that constitutes the metal layer is at least one metal selected from the group consisting of Ta, Nb, Ti, W, Ba, La, Sr, Ca, Fe, Bi, V, Zn, Cu, Ni, Pb, Ag, Cd, Ga, In, Sm, and Mg.

9. The method for producing a photocatalyst electrode for water decomposition according to claim 8 , further comprising:

after the photocatalyst layer forming step and before the current collecting layer forming step, a contact layer forming step of forming a contact layer containing a semiconductor or a good conductor on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate.

10. The method for producing a photocatalyst electrode for water decomposition according to claim 8 , further comprising:

after the current collecting layer forming step and before the detachment step, a second substrate laminating step of laminating a second substrate on a surface of the current collecting layer, the surface being on the opposite side of the photocatalyst layer.

11. The method for producing a photocatalyst electrode for water decomposition according to claim 8 , wherein the photocatalyst layer has a thickness of 100 nm to 1,200 nm.

12. The method for producing a photocatalyst electrode for water decomposition according to claim 8 , wherein the first substrate is a silicon substrate.

13. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , further comprising:

after the photocatalyst layer forming step and before the current collecting layer forming step, a contact layer forming step of forming a contact layer containing a semiconductor or a good conductor on a surface of the photocatalyst layer, the surface being on the opposite side of the first substrate.

14. The method for producing a photocatalyst electrode for water decomposition according to claim 13 , further comprising:

after the current collecting layer forming step and before the detachment step, a second substrate laminating step of laminating a second substrate on a surface of the current collecting layer, the surface being on the opposite side of the photocatalyst layer.

15. The method for producing a photocatalyst electrode for water decomposition according to claim 13 , wherein the photocatalyst layer has a thickness of 100 nm to 1,200 nm.

16. The method for producing a photocatalyst electrode for water decomposition according to claim 13 , wherein the first substrate is a silicon substrate.

17. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , further comprising:

after the current collecting layer forming step and before the detachment step, a second substrate laminating step of laminating a second substrate on a surface of the current collecting layer, the surface being on the opposite side of the photocatalyst layer.

18. The method for producing a photocatalyst electrode for water decomposition according to claim 17 , wherein the photocatalyst layer has a thickness of 100 nm to 1,200 nm.

19. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , wherein the photocatalyst layer has a thickness of 100 nm to 1,200 nm.

20. The method for producing a photocatalyst electrode for water decomposition according to claim 1 , wherein the first substrate is a silicon substrate.