Method for generating hydrogen by decoupled water electrolysis

Patent metadata

Field	Value
Publication number	US-2024327998-A1
Application number	US-202218577608-A
Country	US
Kind code	A1
Filing date	Jul 7, 2022
Priority date	Jul 7, 2021
Publication date	Oct 3, 2024
Grant date	—

Abstract

A method for generating hydrogen by water electrolysis, comprising only a positive electrode based on a bifunctional catalyst successively forming an oxygen evolution reaction (OER) electrode and a hydrogen evolution reaction (HER) electrode, depending if the device is subjected to or produces an electric charge, and a negative electrode using a redox pair Mm+/M, wherein M represents a metal element in reduced form and Mm+ represents said metal element in oxidized form, submerged in an aqueous electrolyte, comprising performing biased electrolysis to cause, at the negative electrode, the metal element in oxidized form Mm+ to be reduced to a reduced metal element M in solid form, the metal exhibiting an H2 overvoltage, and to cause, at the positive electrode, O2 to be generated to form the OER electrode and performing spontaneous reaction conversion between the positive electrode generating H2, to form the HER electrode, and the negative electrode at which the M is oxidized into Mm+.

First claim

1 . A method for generating hydrogen by water electrolysis, wherein same uses an electrochemical device comprising only two electrodes, namely a positive electrode containing a bifunctional catalyst successively forming an oxygen evolution reaction electrode and a hydrogen evolution reaction electrode, according to whether the device is subjected to an electric charge or produces an electric charge, and a negative electrode using a redox pair M m+ /M, wherein M represents a metal element in reduced form and M m+ represents said metal element in oxidized form, the electrodes being immersed in an aqueous electrolyte, the method comprising-at-least:
a step of electrolysis under biasing inducing, at the negative electrode, a reduction of the metal element in oxidized form M m+ to a reduced metal element M in solid form, the metal exhibiting an H 2 overvoltage, and inducing, at the positive electrode, the generation of oxygen O 2 forming the OER electrode; a step of conversion by spontaneous reaction, between the positive electrode generating hydrogen H 2 , forming the HER electrode, and the negative electrode, seat of the oxidation of the metal element in reduced form M into a metal element in oxidized form M m+ .

2 . The method according to claim 1 , wherein the reduced metal element M in solid form forms a deposit on the negative electrode.

3 . The method according to claim 1 , wherein the step of conversion by spontaneous reaction generates an electrical voltage, giving rise to an effective electrical energy.

4 . A method according to claim 1 , wherein M represents Pb and M m+ represents PbSO 4 and the electrolyte comprises H 2 SO 4 .

5 . The method according to claim 1 , wherein M represents Zn and M m+ represents Zn 2+ and the electrolyte is basic.

6 . The device for implementing the method according to claim 1 , wherein same comprises:
at least one closed chamber intended to contain at least one aqueous electrolyte; at least one positive electrode capable of forming an OER electrode and an HER electrode intended to be immersed in the electrolyte; at least one negative electrode forming a redox electrode intended to be immersed in the electrolyte; a power supply connected to the positive electrode and to the negative electrode; an electrical connection for managing the charge and discharge of the device, apt to successively produce the functioning the positive electrode as OER electrode and as HER electrode; at least one discharge pipe for the gaseous oxygen generated by the method, and independently, at least one discharge pipe for the gaseous hydrogen generated by the method.

7 . The device according to claim 6 , wherein same comprises only two electrodes.

8 . The device according to claim 6 , wherein same comprises a device for storing the gaseous hydrogen generated by the method- and a device for storing the gaseous oxygen generated by the method.

Assignees

• Totalenergies Onetech

Inventors

• Aymé-Perrot David

Classifications

• H01M2300/0011

  Sulfuric acid-based · CPC title

• H01M8/065

  by dissolution of metals or alloys; by dehydriding metallic substances · CPC title

• C25B5/00

  Electrogenerative processes, i.e. processes for producing compounds in which electricity is generated simultaneously · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title