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

Patent metadata

Field	Value
Publication number	US-2021002777-A1
Application number	US-201916968813-A
Country	US
Kind code	A1
Filing date	Feb 1, 2019
Priority date	Feb 14, 2018
Publication date	Jan 7, 2021
Grant date	—

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

1 . An anode for oxygen evolution reaction in water including chloride, comprising:
a substrate; a passivation layer coating the substrate; and an electrocatalyst layer coating the passivation layer, wherein the passivation layer includes a sulfide of at least one metal.

2 . The anode of claim 1 , wherein the passivation layer includes nickel sulfide or nickel iron sulfide.

3 . The anode of claim 2 , further comprising an anionic layer disposed between the passivation layer and the electrocatalyst layer.

4 . The anode of claim 3 , wherein the anionic layer includes an anionic oxide of sulfur.

5 . An anode for oxygen evolution reaction in water including chloride, comprising:
a substrate; a passivation layer coating the substrate; and an electrocatalyst layer coating the passivation layer, wherein the passivation layer includes a phosphide of at least one metal.

6 . The anode of claim 5 , wherein the passivation layer includes nickel phosphide or nickel iron phosphide.

7 . The anode of claim 6 , further comprising an anionic layer disposed between the passivation layer and the electrocatalyst layer.

8 . The anode of claim 7 , wherein the anionic layer includes an anionic oxide of phosphorus.

9 . An anode for oxygen evolution reaction in water including chloride, comprising:
a substrate; an electrocatalyst layer coating the substrate; and an anionic layer disposed between the substrate and the electrocatalyst layer.

10 . The anode of claim 9 , wherein the anionic layer includes polyatomic anions including carbonate, sulfate, phosphate, or a combination of two or more thereof.

11 . The anode of claim 10 , wherein the polyatomic anions include an anionic oxide of sulfur.

12 . The anode of claim 10 , wherein the polyatomic anions include an anionic oxide of phosphorus.

13 . The anode of claim 10 , wherein the polyatomic anions include carbonate; an anionic oxide of molybdenum, tungsten, vanadium, chromium, boron, or carbon; or a combination thereof.

14 . The anode of claim 9 , wherein the electrocatalyst layer includes 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.

15 . An anode for oxygen evolution reaction in water including chloride, comprising:
a substrate; and an electrocatalyst layer coating the substrate, wherein the electrocatalyst layer includes anions.

16 . The anode of claim 15 , wherein the anions are intercalated within the electrocatalyst layer and an interface between the electrocatalyst layer and the substrate.

17 . The anode of claim 16 , wherein the electrocatalyst layer includes an anion or mixture anion-intercalated metal hydroxide, an anion or mixture anion-intercalated mixed metal hydroxide, an anion or mixture anion-intercalated metal-layered double hydroxide, an anion or mixture anion-intercalated mixed metal-layered double hydroxide, an anion or mixture anion-intercalated metal oxide, or an anion or mixture anion-intercalated mixed metal oxide.

18 . The anode of claim 15 , wherein the anions include polyatomic anions including carbonate, sulfate, phosphate, or a combination of two or more thereof.

19 . The anode of claim 18 , wherein the polyatomic anions include an anionic oxide of sulfur, phosphorus, or carbon.

20 . The anode of claim 15 , wherein the substrate is a metallic foam, foil, or mesh.

21 . The anode of claim 15 , wherein the substrate includes nickel.

22 . A water electrolyzer comprising the anode of claim 15 .

23 . A method of operating the water electrolyzer of claim 22 , comprising generating oxygen and hydrogen from water including sodium chloride.

24 . The method of claim 23 , wherein the water is alkaline seawater with a pH greater than 7.

25 . A method of operating a water electrolyzer, 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 is in a range of 0.05 M to 8 M.

26 . The method of claim 25 , wherein the polyatomic anions include CO 3 2− , HCO 3 − , SO 4 2− , SO 3 2− , PO 4 3− , H 2 PO 4 − , HPO 4 2− , or a combination of two or more thereof.

27 . The method of claim 25 , wherein the concentration of the polyatomic anions is from 0.05 M to 2 M.

28 . A method of manufacturing an anode for oxygen evolution reaction, comprising:
providing a substrate; forming a passivation layer coating the substrate; and forming an electrocatalyst layer coating the passivation layer, thereby forming the anode including the substrate, the passivation layer, and the electrocatalyst layer.

29 . The method of claim 28 , further comprising applying a current to the substrate to form an anionic layer disposed between the passivation layer and the electrocatalyst layer.

30 . A method of manufacturing an anode for oxygen evolution reaction, comprising:
providing a substrate includes a transition metal; forming an electrocatalyst layer coating the substrate; and applying a current to the substrate to form an anionic layer disposed between the substrate and the electrocatalyst layer, wherein the anionic layer includes an anionic oxide of the transition metal.

31 . A method of manufacturing an anode for oxygen evolution reaction, comprising:
providing a substrate; and forming an electrocatalyst layer coating the substrate, thereby forming the anode including the substrate and the electrocatalyst layer, wherein forming the electrocatalyst layer is in the presence of an electrolyte solution including anions, and the anions are incorporated within the electrocatalyst layer.

32 . The method of claim 31 , wherein the anions include sulfate, phosphate, carbonate, or a combination of two or more thereof.

33 . The method of claim 31 , wherein forming the electrocatalyst layer is performed by anodization of the substrate in the presence of the electrolyte solution.

34 . The method of claim 31 , wherein the substrate includes a transition metal, and forming the electrocatalyst layer includes forming an anion-intercalated transition metal hydroxide or an anion-intercalated transition metal-layered double hydroxide.

35 . A method of manufacturing an anode for oxygen evolution reaction, comprising:
providing a substrate; forming a precursor layer coating the substrate; and forming, from the precursor layer, an electrocatalyst layer coating the substrate, thereby forming the anode including the substrate and the electrocatalyst layer, wherein forming the electrocatalyst layer is in the presence of an electrolyte solution including anions, and the anions are incorporated within the electrocatalyst layer.

36 . The method of claim 35 , wherein the substrate includes a first metal, and forming the precursor layer includes exposing the substrate to a precursor solution including at least one second metal different from the first metal.

37 . The method of claim 36 , wherein the first metal is

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