Highly sustained electrodes and electrolytes for salty alkaline and neutral water splitting

Patent metadata

Field	Value
Publication number	US-11326265-B2
Application number	US-201916968813-A
Country	US
Kind code	B2
Filing date	Feb 1, 2019
Priority date	Feb 14, 2018
Publication date	May 10, 2022
Grant date	May 10, 2022

Abstract

A corrosion resistant anode is provided for oxygen evolution reaction in water including chloride ions. The anode includes: (1) a substrate; (2) a passivation layer coating the substrate; and (3) an electrocatalyst layer coating the passivation layer. Polyanion adjusted alkaline seawater electrolyte for hydrogen generation by electrolysis is also provided.

First claim

What is claimed is:

1. An anode for oxygen evolution in water including chloride, comprising:
a substrate;
a passivation layer coating the substrate;
an anionic layer comprising an anionic oxide of sulfur; and
an electrocatalyst layer coating, wherein the anionic layer is disposed at an interface between the passivation layer coating and the electrocatalyst layer coating.

2. The anode of claim 1 , wherein the electrocatalyst comprises a metal hydroxide, a mixed metal hydroxide, a metal-layered double hydroxide, a mixed metal-layered double hydroxide, a metal oxide or a mixed metal oxide.

3. The anode of claim 1 , wherein the passivation layer comprising a nickel sulfide or nickel-iron sulfide.

4. The anode of claim 1 , wherein the substrate is a metallic foam, foil or mesh.

5. The anode of claim 1 , wherein the substrate comprises nickel.

6. A water electrolyzer comprising the anode of claim 1 .

7. A method of operating the water electrolyzer of claim 6 , comprising generating oxygen and hydrogen from water including sodium chloride.

8. The method of claim 7 , wherein the water is alkaline seawater.

9. A method of operating a water electrolyzer containing the anode of claim 1 , comprising generating oxygen and hydrogen from an electrolyte, wherein the electrolyte includes alkaline adjusted seawater and polyatomic anions dispersed in the alkaline adjusted seawater with precipitated alkaline earth and heavy metal ions removed by filtration and a concentration of the polyatomic anions in the electrolyte in a range of 0.05 M to 8 M.

10. The method of claim 9 , wherein the polyatomic anions include CO 3 2− , HCO 3 − , SO 4 2− , SO 3 2− , PO 4 2− , H 2 PO 4 2− , HPO 4 2− , or a combination of two or more thereof.

11. The method of claim 9 , wherein the concentration of the polyatomic anions is from 0.05 M to 2 M.

12. A method of manufacturing the anode for oxygen evolution according to claim 1 , comprising:
providing a substrate;
forming the passivation layer coating on the substrate;
forming the electrocatalyst layer coating on the passivation layer coating; and
applying a current to the substrate to form the anionic layer disposed at the interface between the passivation layer coating and the electrocatalyst layer coating.

13. The method of claim 11 , wherein the forming the anionic layer further comprising applying the current to the substrate in the presence of an electrolyte comprising sulfate.

Assignees

• Univ Leland Stanford Junior

Inventors

• Kenney Michael J
• Dai Hongjie
• Kuang yun
• Meng Yongtao

Classifications

• C25D11/36

  Phosphatising · CPC title

• C25D11/34

  of metals or alloys not provided for in groups C25D11/04 - C25D11/32 · CPC title

• C25D9/08

  by cathodic processes · CPC title

• C25D9/06

  by anodic processes · CPC title

• C25D5/12

  at least one layer being of nickel or chromium · CPC title