Methods and system for hydrogen production by water electrolysis

Patent metadata

Field	Value
Publication number	US-11208729-B2
Application number	US-201916599351-A
Country	US
Kind code	B2
Filing date	Oct 11, 2019
Priority date	Nov 19, 2014
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

A system and method for generating hydrogen gas from an aqueous solution are disclosed herein. The system comprises a compartment with a working electrode for reducing water in response to an applied voltage to generate hydrogen and a redox-active electrode capable of reversibly undergoing oxidation and reduction. The system may further comprise a second compartment with a working electrode for generating oxygen and redox-active electrode electrically connectable to the redox-active electrode in the first compartment. The method comprises applying a voltage between a working electrode and a redox-active electrode of a system described herein and/or between comprising a working electrode of one compartment and a working electrode of a second compartment of a system described herein.

First claim

The invention claimed is:

1. A system for generation of oxygen gas from an aqueous solution, the system comprising:
a compartment comprising a working electrode and a redox-active electrode, wherein said compartment containing an aqueous solution optionally comprising hydroxide ions, and wherein said compartment is a non-partitioned compartment having an inlet configured for receiving an aqueous solution, and at least one gas outlet configured for controllably evacuating a gas from the compartment,
said redox-active electrode being in an oxidized state and configured to undergo reduction in the absence of electrical bias to generate oxygen gas.

2. The system according to claim 1 , wherein said redox-active electrode being capable of reversibly undergoing oxidation in response to an applied electrical bias between the working electrode and the redox-active electrode of at least 1.23V when measured at 25° C.

3. The system according to claim 1 , wherein said oxidized redox-active electrode comprises nickel oxyhydroxide (NiOOH).

4. A system for generation of oxygen gas from an aqueous solution, the system comprising:
a non-partitioned compartment comprising said a working electrode and said a redox-active electrode, wherein said compartment containing an aqueous solution optionally comprising hydroxide ions;
said compartment having an inlet configured for receiving an aqueous solution, and at least one gas outlet configured for controllably evacuating a gas from the compartment,
said redox-active electrode comprises nickel oxyhydroxide (NiOOH) capable of reversibly undergoing reduction in the absence of bias and subsequent oxidation under an applied bias applied between the working electrode and redox-active electrode of at least 1.23V when measured at 25° C.

5. A method for generating oxygen gas, in a non-partitioned cell, the method comprising
in a system operating under an applied electrical bias between a working electrode and an oxidized redox-active electrode;
stopping the bias or applying a stimulation to said cell to cause the oxidized redox-active electrode to generate oxygen gas.

Assignees

• Technion Res & Dev Foundation

Inventors

• Rothschild Avner
• Grader Gideon
• Shter Gennady
• Landman Avigail
• Dotan Hen

Classifications

• C25B15/00

  Operating or servicing cells · CPC title

• C25B1/55

  Photoelectrolysis · CPC title

• C25B11/04

  characterised by the material · CPC title

• C25B1/04 Primary

  by electrolysis of water · CPC title

• C25B9/17

  Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof · CPC title