Titanium-based metal micropore back layer for PEM electrolytic bath

Abstract

The utility model relates to a titanium-based metal micropore back layer for a PEM electrolytic bath, which belongs to the technical field of hydrogen production equipment and comprises a pore layer (1) arranged between a current collector (2) and a catalyst layer (3). Holes with different hole diameters are formed in the hole layer (1). The PEM electrolytic cell is used for improving the contact efficiency and the quality transmission performance between the current collector and the catalyst layer of the PEM electrolytic cell, has good adhesiveness and durability, and improves the electrochemical performance of the electrolytic cell; bubble management is improved, quality transmission limitation is reduced, and particularly, performance improvement under high current density is more remarkable.

Description

Technical Field

[0001] The utility model relates to the technical field of hydrogen production equipment, in particular to a titanium-based metal microporous back layer for a PEM electrolytic cell. Background Art

[0002] In a PEM electrolyzer, the contact resistance (ICR) between the current collector (CC) and the catalyst layer (CL) has a significant impact on the overall performance. Traditional CCs are mostly porous structures of titanium, but their microstructure optimization still needs to be improved. In the existing technology, precious metal coatings are often used to reduce the ICR overpotential, but this is costly, and at high current density, bubble management becomes a bottleneck for performance improvement. Utility Model Content

[0003] In order to solve the above-mentioned prior art problems, the utility model provides a titanium-based metal microporous back layer for a PEM electrolyzer, comprising: a pore layer arranged between a current collector and a catalyst layer; and pores with different pore sizes are arranged in the pore layer.

[0004] Furthermore, the pores include inner pores and outer pores, the inner pores are close to the catalyst layer side, and the outer pores are close to the current collector side.

[0005] Furthermore, the diameter of the inner layer holes is smaller than the diameter of the outer layer holes.

[0006] Furthermore, the porosity of the porous layer on the side close to the current collector is greater than the porosity on the side close to the catalyst layer.

[0007] Furthermore, the porous layer is formed by depositing multiple layers of titanium metal on the current collector.

[0008] Furthermore, the thickness of the porous layer is 13.4 μm.

[0009] Furthermore, the average pore size of the pores in the porous layer is 1.6 μm, and the overall porosity of the porous layer is 9.3%.

[0010] Beneficial effects of the utility model: The utility model is used to improve the contact efficiency and mass transfer performance between the current collector and the catalyst layer of the PEM electrolyzer, has good adhesion and durability, and improves the electrochemical performance of the electrolyzer; improves bubble management, reduces mass transfer limitations, and the performance improvement is more significant especially at high current density. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of the utility model.

[0012] Figure numerals: 1, pore layer; 2, current collector; 3, catalyst layer; 4, inner layer pores; 5, outer layer pores. DETAILED DESCRIPTION

[0013] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0014] Embodiment 1:

[0015] Reference Figure 1 A titanium-based metal microporous back layer for a PEM electrolyzer comprises: a pore layer 1 arranged between a current collector 2 and a catalyst layer 3; and pores of different pore sizes are arranged in the pore layer 1.

[0016] The pores include inner pores 4 and outer pores 5 , wherein the inner pores 4 are close to the catalyst layer 3 and the outer pores 5 are close to the current collector 2 .

[0017] The diameter of the inner layer holes 4 is smaller than the diameter of the outer layer holes 5 .

[0018] The porosity of the porous layer 1 on the side close to the current collector is greater than the porosity on the side close to the catalyst layer.

[0019] The porous layer 1 is formed by depositing multiple layers of titanium metal on the current collector.

[0020] In this embodiment 1, VPS technology is used to 2 Two layers of titanium were deposited on the sintered titanium filter to form the MPL (Titanium-based Microporous Metal Backing Layer). Only the CC side in contact with the CL was coated. Grade 1 titanium (particle size less than 45μm) was used as the raw powder. The MPL had an average thickness of 13.4μm, a porosity of about 9.3%, and an average pore size of 1.6μm. Tested in a 25cm² single PEM electrolyser cell, the MPL backing layer showed a significantly higher yield at 2Acm compared to the uncoated CC. -2 The overpotential reduction was shown to be at least 40 mV at a current density of 1.3 Å.

[0021] In this Example 1, a titanium-based metal microporous back layer is prepared by depositing multiple layers of titanium metal on a titanium-based CC by vacuum plasma spraying (VPS) technology; VPS parameters, including chamber pressure, substrate preheating temperature, gas flow rate, and spray gun scanning rate, are adjusted to control the porosity, pore size, and roughness of the MPL.

[0022] The structural design of the titanium-based metal microporous back layer has a gradient pore size structure with small porosity in the inner layer and large pore size in the outer layer to optimize water management and bubble release; the thickness, pore size and porosity of the titanium-based metal microporous layer back layer structure are optimized through image analysis to achieve the best contact area and electrical conductivity performance.

[0023] Optimization of contact resistance and mass transfer: The application of the utility model can significantly reduce the contact resistance by about 20mΩcm² and improve the efficiency of the electrolytic cell at high current density; through the titanium-based metal microporous back layer structure, the gas transmission is improved, the retention of bubbles on the CC is reduced, thereby improving the mass transfer efficiency.

[0024] In the description of the embodiments of the present utility model, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "center", "top", "bottom", "top", "bottom", "inside", "outside", "inner side", "outer side" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. Among them, "inside" refers to an internal or enclosed area or space. "Periphery" refers to the area surrounding a specific component or a specific area.

[0025] In the description of the embodiments of the present utility model, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, the meaning of "multiple" is two or more.

[0026] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", and "assemble" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the description of the embodiments of the present invention, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0028] In the description of the embodiments of the present utility model, it should be understood that "-" and "~" represent the range between two values, and the range includes the endpoints. For example: "AB" represents a range greater than or equal to A and less than or equal to B. "A~B" represents a range greater than or equal to A and less than or equal to B.

[0029] In the description of the embodiments of the present utility model, the term "and / or" herein is only a kind of association relationship of describing the associated objects, indicating that there may be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " herein generally indicates that the associated objects before and after are in an "or" relationship.

[0030] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A titanium-based metal microporous back layer for a PEM electrolyzer, characterized in that: include: A porous layer (1) is arranged between a current collector (2) and a catalyst layer (3); the porous layer (1) is provided with holes of different pore sizes; the holes include inner layer holes (4) and outer layer holes (5), the inner layer holes (4) are close to the catalyst layer (3) side, and the outer layer holes (5) are close to the current collector (2) side; the pore diameter of the inner layer holes (4) is smaller than the pore diameter of the outer layer holes (5).

2. The titanium-based metal microporous back layer for a PEM electrolyzer according to claim 1, characterized in that: The porosity of the porous layer (1) on the side close to the current collector is greater than the porosity on the side close to the catalyst layer.

3. The titanium-based metal microporous back layer for a PEM electrolyzer according to claim 1, characterized in that: The porous layer (1) is formed by depositing multiple layers of titanium metal on the current collector.

4. The titanium-based metal microporous back layer for a PEM electrolyzer according to claim 1, characterized in that: The thickness of the porous layer (1) is 13.4 μm.

5. The titanium-based metal microporous back layer for a PEM electrolyzer according to claim 1, characterized in that: The average pore diameter of the pores in the porous layer (1) is 1.6 μm, and the overall porosity of the porous layer (1) is 9.3%.

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