Alkaline water electrolysis method, and anode for alkaline water electrolysis

Patent metadata

Field	Value
Publication number	US-11692276-B2
Application number	US-202117905232-A
Country	US
Kind code	B2
Filing date	Mar 8, 2021
Priority date	Mar 9, 2020
Publication date	Jul 4, 2023
Grant date	Jul 4, 2023

Abstract

The present invention realizes industrially excellent effects such that when electric power having a large output fluctuation, such as renewable energy, is used as a power source, electrolysis performance is unlikely to be deteriorated and excellent catalytic activity is retained stably over a longer period of time, and in addition, the present invention provides a technique that enables forming a catalyst layer of an oxygen generation anode, which gives such excellent effects, with a more versatile materials and by a simple electrolysis method. Provided are an alkaline water electrolysis method including supplying an electrolyte obtained by dispersing a catalyst containing a hybrid nickel-iron hydroxide nanosheet (NiFe-ns) being a composite of a metal hydroxide and an organic substance to an anode chamber and a cathode chamber, and using the electrolyte for electrolysis in each chamber in common, an alkaline water electrolysis method including supplying an electrolyte obtained by dispersing a catalyst containing the NiFe-ns to an anode chamber and a cathode chamber, and performing electrolytic deposition of the NiFe-ns in the electrolytic cell during operation to electrolytically deposit the NiFe-ns on a surface of an electrically conductive substrate having a catalyst layer formed on a surface of an oxygen generation anode, thereby recovering and improving electrolysis performance, and an alkaline water electrolysis anode.

First claim

The invention claimed is:

1. An alkaline water electrolysis method comprising
supplying an electrolyte obtained by dispersing a catalyst comprising a hybrid nickel-iron hydroxide nanosheet (NiFe-ns) being a composite of a metal hydroxide and an organic substance to an anode chamber and a cathode chamber that form an electrolytic cell, and using the electrolyte for electrolysis in each chamber in common.

2. An alkaline water electrolysis method comprising:
supplying an electrolyte obtained by dispersing a catalyst comprising a hybrid nickel-iron hydroxide nanosheet (NiFe-ns) being a composite of a metal hydroxide and an organic substance to an anode chamber and a cathode chamber that form an electrolytic cell, and using the electrolyte for electrolysis in each chamber in common; and
performing electrolytic deposition of the NiFe-ns in the electrolytic cell during operation to electrolytically deposit the NiFe-ns on a surface of an electrically conductive substrate that forms an oxygen generation anode and has a catalyst layer formed on a surface thereof, thereby recovering and improving electrolysis performance.

3. The alkaline water electrolysis method according to claim 1 , wherein the NiFe-ns has a layered molecular structure having a size of 10 to 100 nm.

4. The alkaline water electrolysis method according to claim 2 , wherein a condition of electrolytically depositing the NiFe-ns on the surface of the electrically conductive substrate is to retain the electrically conductive substrate in a potential range of 1.2 V to 1.8 V vs. RHE.

5. The alkaline water electrolysis method according to claim 1 , wherein an electrolyte prepared using the NiFe-ns dispersion liquid having a concentration of 10 to 100 g/L in such a way that a concentration of the NiFe-ns dispersion liquid added to the electrolyte falls within a range of 0.1 to 5 mL/L is used as the electrolyte obtained by dispersing the NiFe-ns.

6. An alkaline water electrolysis anode that performs oxygen generation, the alkaline water electrolysis anode comprising:
an electrically conductive substrate having a surface comprising nickel or a nickel base alloy;
an intermediate layer formed on the surface of the electrically conductive substrate, the intermediate layer comprising a lithium-containing nickel oxide represented by compositional formula Li x Ni 2-x O 2 wherein 0.02≤x≤0.5; and
a catalyst layer formed on a surface of the intermediate layer, the catalyst layer comprising a hybrid nickel-iron hydroxide nanosheet (NiFe-ns) being a composite of a metal hydroxide and an organic substance.

Assignees

• De Nora Permelec Ltd
• Kawasaki Heavy Ind Ltd
• Nat Univ Corp Yokohama Nat Univ

Inventors

• Mitsushima Shigenori
• Kuroda Yoshiyuki
• TAKATSU Shohei
• Nagashima Ikuo
• Taniguchi Tatsuya
• Inomata Akihiko
• Nagai Ayaka
• Nishiki Yoshinori
• Kato Akihiro
• Zaenal Awaludin
• Nakai Takaaki

Classifications

• C25B15/029

  Concentration · CPC title

• C25B15/08

  Supplying or removing reactants or electrolytes; Regeneration of electrolytes · CPC title

• C25B11/077

  the compound being a non-noble metal oxide · CPC title

• C25B11/085

  Organic compound · CPC title

• C25B11/061

  Metal or alloy · CPC title