KR-20260065706-A - POROUS TRANSPORT LAYER FOR WATER ELECTROLYSIS, AND PREPARATION METHOD THEREOF

Abstract

The present invention relates to a method for manufacturing a porous mass transfer layer for water electrolysis, comprising: a coating step (S10) of manufacturing a coated fiber using a coating solution containing a noble metal, wherein the first fiber containing a titanium group element is used to manufacture a coated fiber; and a step (S20) of manufacturing a porous coated body layer by webbing and sintering the coated fiber. The invention also relates to a porous mass transfer layer for water electrolysis manufactured thereby.

Inventors

• 이필영
• 박영준
• 윤수빈

Assignees

• 현대자동차주식회사
• 기아 주식회사

Dates

Publication Date

20260511

Application Date

20241101

Claims (15)

1. A coating step (S10) of manufacturing a coated fiber using a coating solution containing a noble metal on a first fiber containing a titanium group element; and A method for manufacturing a porous mass transfer layer for water electrolysis, comprising the step (S20) of webbing and sintering the above-mentioned coating fibers to manufacture a porous coating layer.
2. In claim 1, A method for manufacturing a porous mass transfer layer for flood control, wherein the first fiber has an average length of 10 cm or more.
3. In claim 2, A method for manufacturing a porous mass transfer layer for water electrolysis, comprising the step (S11) of cutting the coating fiber after the above step (S10).
4. In claim 1, A method for manufacturing a porous mass transfer layer for water electrolysis, wherein the first fiber is manufactured by a pultrusion molding method.
5. In claim 1, A method for manufacturing a porous mass transfer layer for water electrolysis, wherein the above (S10) step is performed by one or more methods selected from the group consisting of electrolytic plating, electroless plating, and vacuum plating.
6. In claim 1, A method for manufacturing a porous mass transfer layer for water electrolysis, wherein the sintering of step (S20) above is performed at a temperature of 900°C or higher and 1,500°C or lower and a vacuum of 10⁻⁵ Torr or lower.
7. In claim 1, A step (S30) of webbing a second fiber containing a titanium group element and sintering it to produce a fiber layer; and A method for manufacturing a porous mass transfer layer for water electrolysis, comprising the step (S40) of manufacturing a multilayer porous mass transfer layer by laminating the porous coating layer and the fiber layer.
8. In claim 7, A method for manufacturing a porous mass transfer layer for water electrolysis, wherein the second fiber has an average length of less than 10 cm.
9. A first fiber comprising a titanium group element; and A porous mass transfer layer for water electrolysis comprising a porous coating layer containing a noble metal and coated over the entire surface of the first fiber.
10. In claim 9, The above coating layer is a porous mass transfer layer for water electrolysis having an average thickness of 5 nm or more and 1000 nm or less.
11. In claim 9, A porous mass transfer layer for water electrolysis, wherein the above titanium group element comprises at least one selected from the group consisting of titanium (Ti), zirconium (Zr) and hafnium (Hf).
12. In claim 9, A porous mass transfer layer for water electrolysis, wherein the precious metal comprises at least one selected from the group consisting of platinum (Pt), gold (Au), iridium (Ir), ruthenium (Ru), palladium (Pd), rhodium (Rh), silver (Ag), and osmium (Os).
13. In claim 9, A porous mass transfer layer for water electrolysis comprising a fiber layer comprising a second fiber comprising a titanium group element on the porous coating layer.
14. A water electrolysis cell comprising a porous mass transfer layer for water electrolysis according to any one of claims 9 to 13.
15. In claim 14, A water electrolysis cell having a membrane-electrode assembly (MEA) laminated on the porous coating layer side of the porous mass transfer layer for water electrolysis.

Description

Porous transport layer for water electrolysis, and method for preparing the same The present invention relates to a porous mass transfer layer for water electrolysis that has excellent electrical and thermal conductivity and can improve the durability and hydrogen production efficiency of a water electrolysis cell containing the same, and a method for manufacturing the same. A Polymer Electrolyte Membrane (PEM) water electrolysis system is an electrochemical conversion device that uses electricity to decompose water ( H₂O ) into hydrogen ( H₂ ) and oxygen ( O₂ ). The PEM water electrolysis system has the advantages of being able to operate at high current densities, enabling the production of high-purity hydrogen and oxygen due to low gas permeability through the solid electrolyte membrane, and ensuring high stability. Typically, such a PEM water electrolysis system consists of a PEM water electrolysis stack and peripheral devices for driving it, and the PEM water electrolysis stack is composed of a plurality of PEM water electrolysis cells. Figure 1 is a cross-sectional view of a conventional polymer electrolyte membrane (PEM) water electrolysis cell. FIG. 2 is a cross-sectional view of a water electrolysis cell according to an embodiment of the present invention. In this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. In this specification, when it is stated that a member is located on the "surface," "one side," "other side," or "both sides" of another member, this includes not only cases where a member is in contact with another member, but also cases where another member exists between the two members. Referring to FIG. 1, a PEM water electrolysis cell typically includes a membrane-electrode assembly (MEA) comprising an electrolyte membrane (10), an anode electrode (20), and a cathode electrode (30), a gas diffusion layer (GDL) (40) for the cathode, a porous transport layer (PTL) (50) for the anode, a cathode separator (60), and an anode separator (70). At this time, water introduced into the anode (20) through the anode separator flow path (a) is supplied through the PTL (50), and hydrogen gas generated in the cathode (30) is discharged through the GDL (40) and the cathode separator flow path (b). In this electrochemical reaction of the PEM water electrolysis cell, water supplied to the anode is separated into hydrogen ions (H + ) and electrons along with oxygen gas by the Oxygen Evolution Reaction (OER), then moves to the cathode through the electrolyte membrane and external circuit, and generates hydrogen gas by the Hydrogen Evolution Reaction. The above PTL serves to uniformly distribute and/or diffuse water, a reactant, onto the surface of the anode electrode, discharge oxygen generated at the anode electrode to the outside through a separator, and collect and/or transport electrons generated by electrochemical reactions. To maximize the functions of this PTL, various physical properties such as corrosion resistance, electrical conductivity, distribution and diffusion properties, low surface roughness, and mechanical strength are essential. Furthermore, it is desirable to use a material for the PTL that has excellent electrical conductivity, thermal conductivity, and corrosion resistance, as well as low ohmic losses and mass transport losses. Accordingly, titanium (Ti)-based materials, which have excellent physical and chemical properties and do not corrode even under high potential and acidic conditions, are widely used in conventional PTLs. Conventional manufacturing methods for PTLs typically involve, for example, manufacturing a porous material using titanium-based fibers and/or powder, and then forming a coating layer to prevent oxide film formation and reduce contact resistance with the electrode. At this time, the methods for forming the coating layer can be divided into dry methods, such as physical vapor deposition (PVD), and wet methods, such as electroplating. Specifically, a manufacturing method for PTLs using titanium-based fibers generally involves processing a titanium block into a fiber shape, webbing it, sintering and rolling it to form a porous layer, and then forming a coating layer on the porous layer. However, methods of forming a coating layer on a porous layer in this manner presented problems, such as the difficulty of forming a coating layer of uniform thickness and the occurrence of uncoated areas, due to the severe surface irregularities and porous nature of the porous layer. In particular, the PVD coating method had limitations in forming a coating layer within the porous layer, specifically in the area where the electrolyte membrane and electrode expand to come into contact with the PTL. Additionally, the electroplating coating method also had limitations, as coating was primarily performed on the surface of the