CN-121992425-A - Membrane electrode assembly for water electrolysis and method for producing same

CN121992425ACN 121992425 ACN121992425 ACN 121992425ACN-121992425-A

Abstract

The invention provides a membrane electrode assembly for water electrolysis and a method for producing the same. The membrane electrode assembly is a membrane electrode assembly for water electrolysis comprising a solid electrolyte membrane, and an anode catalyst layer and a cathode catalyst layer sandwiching the solid electrolyte membrane, wherein the solid electrolyte membrane comprises a solid electrolyte layer and a functional layer formed on the anode side surface of the solid electrolyte layer, the anode catalyst layer is formed on the functional layer side surface of the solid electrolyte membrane, the cathode catalyst layer is formed on the surface opposite to the functional layer side surface of the solid electrolyte membrane, and the functional layer comprises a resin and catalyst metal particles dispersed in the resin.

Inventors

KODAMA TOMOKI
AKITA YASUHIRO

Assignees

丰田自动车株式会社

Dates

Publication Date: 20260508
Application Date: 20250924
Priority Date: 20241106

Claims (4)

1. A membrane electrode assembly for use in electrolysis of water, comprising a solid electrolyte membrane, and an anode catalyst layer and a cathode catalyst layer which sandwich the solid electrolyte membrane, The membrane electrode assembly is characterized in that, The solid electrolyte membrane includes a solid electrolyte layer and a functional layer formed on the anode-side surface of the solid electrolyte layer, The anode catalyst layer is formed on the functional layer-side surface of the solid electrolyte membrane, The cathode catalyst layer is formed on a surface of the solid electrolyte membrane on the opposite side to the functional layer side, The functional layer includes a resin, and catalyst metal particles dispersed in the resin.
2. The membrane electrode assembly according to claim 1, wherein, The catalyst metal particles contain 1 or more catalyst metal particles selected from the group consisting of Pt, au, pd, rh and Ir.
3. A method for producing a membrane electrode assembly for water electrolysis, The method for producing the membrane electrode assembly is characterized by comprising the following steps: A preparation step of preparing an electrolyte membrane sheet having a conventional back sheet and a solid electrolyte membrane adhered to the conventional back sheet, the solid electrolyte membrane including a solid electrolyte layer and a functional layer formed on a surface of the solid electrolyte layer opposite to the conventional back sheet side; A bonding step of laminating an electrolyte membrane sheet and a new back sheet so that the new back sheet is in contact with a surface of the solid electrolyte membrane on the functional layer side, thereby forming a laminate, and heating the laminate while pressing from both sides in the lamination direction, thereby bonding the new back sheet to the surface of the solid electrolyte membrane on the functional layer side by thermocompression bonding; an existing back sheet peeling step of peeling the existing back sheet from the solid electrolyte membrane; A cathode catalyst layer forming step of forming a cathode catalyst layer on a surface of the solid electrolyte membrane opposite to the functional layer side after the conventional back sheet peeling step; A new back sheet peeling step of peeling the new back sheet from the solid electrolyte membrane after the cathode catalyst layer forming step, and And an anode catalyst layer forming step of forming an anode catalyst layer on the functional layer side surface of the solid electrolyte membrane after the new back sheet peeling step.
4. The method for producing a membrane electrode assembly according to claim 3, wherein, In the bonding step, the heating temperature when the laminate is heated while being pressurized from both sides in the lamination direction is set to 120 ℃ or higher and the thermal decomposition temperature or lower.

Description

Membrane electrode assembly for water electrolysis and method for producing same Technical Field The present invention relates to a membrane electrode assembly for electrolysis of water in a water electrolysis apparatus and a method for producing the same. Background In recent years, as a water electrolysis apparatus, an apparatus in which cells for water electrolysis using a solid electrolyte membrane are arranged in a predetermined group has been used. The cell for water electrolysis has a membrane-electrode assembly comprising a solid electrolyte membrane, and an anode catalyst layer and a cathode catalyst layer sandwiching the solid electrolyte membrane. As a membrane electrode assembly for water electrolysis, for example, a membrane electrode assembly is known in which a catalyst layer is formed using a catalyst layer formation product containing catalyst particles and an electrolyte component as main components, and the distribution state of the catalyst particles and the electrolyte component forming the catalyst layer is inclined so as not to cause the electrolyte component in the catalyst layer to be biased in the vicinity of the catalyst layer surface (japanese patent application laid-open No. 2001-303285). Further, as a method for producing a membrane electrode assembly for water electrolysis, for example, there is disclosed a method which is carried out by a roll-to-roll method, comprising a first forming step of forming a catalyst layer of either an anode or a cathode on a second surface opposite to the first surface in a state where a support film for holding the electrolyte membrane in an expanded state is adhered to the first surface of an elongated electrolyte membrane, a first adhering step of peeling a holding member from the first surface of the electrolyte membrane, adhering a diffusion member constituting a diffusion layer for diffusing a fluid of a fuel or an oxidant necessary for an electrochemical reaction constituting a fuel cell to the second surface, a second forming step of forming the other catalyst layer on the first surface, and a second adhering step of adhering a diffusion member to the first surface (Japanese patent application laid-open No. 2015-35256). In the conventional membrane electrode assembly for water electrolysis and the method for producing the same, the composition of the catalyst layer, the method for forming the catalyst layer, and the like are improved in order to improve the water electrolysis performance of the water electrolysis cell. On the other hand, in order to secure the safety of the water electrolysis cell, it is necessary to suppress the generation of the oxyhydrogen gas having explosiveness by blocking the permeation of the hydrogen gas generated on the cathode side through the solid electrolyte membrane. It is required to improve the blocking performance against hydrogen permeation through the solid electrolyte membrane. Disclosure of Invention The present invention has been made in view of the above-described points, and an object of the present invention is to provide a membrane electrode assembly for water electrolysis that can improve the blocking performance against hydrogen permeation through a solid electrolyte membrane, and a method for producing the same. In order to solve the above problems, the membrane electrode assembly according to the present invention is a membrane electrode assembly for water electrolysis comprising a solid electrolyte membrane, and an anode catalyst layer and a cathode catalyst layer sandwiching the solid electrolyte membrane, wherein the solid electrolyte membrane comprises a solid electrolyte layer, and a functional layer formed on a surface of the solid electrolyte layer on the anode side, the anode catalyst layer is formed on a surface of the solid electrolyte membrane on the functional layer side, the cathode catalyst layer is formed on a surface of the solid electrolyte membrane on the opposite side of the functional layer side, and the functional layer comprises a resin, and catalyst metal particles dispersed in the resin. The method for producing a membrane electrode assembly for water electrolysis is characterized by comprising a preparation step of preparing an electrolyte membrane sheet having an existing back sheet (sometimes simply referred to as "BS") and a solid electrolyte membrane attached to the existing back sheet, the solid electrolyte membrane comprising a solid electrolyte layer and a functional layer formed on the surface of the solid electrolyte layer opposite to the existing back sheet side, a bonding step of laminating an electrolyte membrane sheet and a new back sheet so that a new back sheet is in contact with the surface of the solid electrolyte membrane on the functional layer side, and heating the laminate while pressing the laminate from both sides in the lamination direction, thereby attaching the new back sheet to the surface of the solid electrolyte membrane on the functional