A cathode plate mesh for water electrolysis, its preparation method, and electrolysis apparatus.
By spraying a nickel-aluminum hybrid coating onto the surface of the electrode plate mesh and forming a nickel-aluminum alloy using laser heating, the problem of insufficient bonding strength of the catalyst layer was solved, and a highly efficient and stable water electrolysis hydrogen production process was achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HANDAN KELING NEW MATERIALS CO LTD
- Filing Date
- 2024-06-27
- Publication Date
- 2026-06-02
Smart Images
Figure CN118756201B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of water electrolysis for hydrogen production technology, and more specifically, to a cathode plate mesh for water electrolysis, its preparation method, and an electrolysis apparatus. Background Technology
[0002] Hydrogen energy, as a clean energy source, has been widely promoted. Utilizing renewable energy for power generation and alkaline water electrolysis to produce green hydrogen is one of the most promising methods for hydrogen production. One of the key factors restricting the industrial application of water electrolysis hydrogen production technology is the cost of electricity. Therefore, developing highly active and stable catalytic electrodes for water electrolysis hydrogen production to achieve higher current densities is one of the important development directions for water electrolysis hydrogen production electrodes.
[0003] Currently, there are numerous methods for preparing water electrolysis electrodes. These include hydrothermal methods to synthesize transition metal-based catalysts on substrates such as nickel foam; electroplating to deposit alloy, sulfide, and nitride coatings on conductive substrates; and coating methods to deposit noble metal and oxide catalysts. However, these methods are often complex, requiring multiple drying and sintering processes, resulting in time-consuming procedures, low efficiency, and high costs. The most mainstream industrial technology is still based on plasma spraying, using a simple nickel-aluminum mixture to prepare a nickel-aluminum mixed coating on the surface of a pure nickel electrode. This method currently offers relatively reliable overall performance. However, during use, under the continuous and intense scouring of large amounts of hydrogen and water, especially under high pressure and high temperature operating conditions, conventional plasma spraying methods struggle to ensure a tight bond between the deposited nickel particles and the nickel electrode substrate. This leads to the peeling, detachment, and loss of the catalyst layer, resulting in increased internal resistance and decreased performance of the membrane electrode, which is extremely detrimental to maintaining the electrode's performance, stability, and lifespan.
[0004] Therefore, improving the bonding between the catalyst layer and the electrode body while enhancing electrolysis efficiency can extend the service life, which is one of the bottlenecks facing the development of water electrolysis electrodes. Currently, there is an urgent need to develop a plasma spraying process suitable for large-scale industrial production, enabling the prepared catalyst-coated electrodes to possess advantages such as high specific surface area and high bonding strength.
[0005] In view of this, the present invention is proposed. Summary of the Invention
[0006] The purpose of this invention is to provide a cathode plate mesh for water electrolysis, its preparation method and electrolysis device, aiming to provide a simple and easy method to manufacture a porous nickel coating with high interfacial bonding strength and high activity on the surface of the electrode plate mesh.
[0007] This invention is implemented as follows:
[0008] In a first aspect, the present invention provides a method for preparing a cathode plate mesh for water electrolysis, comprising:
[0009] Using atmospheric plasma spraying, molten nickel and aluminum droplets are sprayed onto the heated electrode plate mesh to form a nickel-aluminum mixed coating.
[0010] The nickel-aluminum hybrid coating is heated to form a nickel-aluminum alloy.
[0011] In an optional implementation, the deposition rate of the molten nickel and aluminum droplets is less than 150 m / s;
[0012] Preferably, the deposition rate of the molten nickel and aluminum droplets is 50 m / s to 80 m / s.
[0013] In an optional embodiment, nickel powder and aluminum powder are used as raw materials and melted into nickel droplets and aluminum droplets, with a mass ratio of nickel powder to aluminum powder of 1:(0.2-0.3).
[0014] Preferably, the particle size range of both nickel powder and aluminum powder is 45μm-78μm;
[0015] Preferably, the purity of both nickel powder and aluminum powder is greater than 99.5%.
[0016] In an optional embodiment, the surface of the electrode plate is heated to 200°C-300°C using a pretreatment laser heating system, and then nickel droplets and aluminum droplets are sprayed on.
[0017] Preferably, the surface of the electrode plate is heated to 250°C-280°C using a pretreatment laser heating system;
[0018] Preferably, the power of the pretreatment laser heating system is 1KW-2KW.
[0019] In an optional embodiment, a post-processing laser is used to heat the nickel-aluminum hybrid coating to 500°C-600°C, and the laser power of the post-processing laser is controlled to be 4KW-6KW.
[0020] In an optional embodiment, the surface of the electrode plate mesh is heated using a pre-processing laser heating head in the pre-processing laser heating system, and the nickel-aluminum mixed coating is heated using a post-processing laser heating head.
[0021] The pretreatment laser heating head, atmospheric plasma spray gun and posttreatment laser heating head are fixed on a movable slide rail in sequence, so that the pretreatment laser heating head, atmospheric plasma spray gun and posttreatment laser heating head move in conjunction with each other along the same trajectory and speed. The posttreatment laser heating head irradiates the deposited nickel-aluminum mixed coating area, and the overall horizontal moving speed is controlled to be 500mm / s-1000mm / s.
[0022] Preferably, the spacing of atmospheric plasma spraying is 500mm-600mm;
[0023] Preferably, the atmospheric plasma spray gun is controlled to move in a zigzag deposition path. When moving in the opposite direction, the roles and powers of the pre-processing laser heating head and the post-processing laser heating head are interchanged.
[0024] In an optional embodiment, the light spots of both the pre-treatment laser heating head and the post-treatment laser heating head are square light spots, and the nickel-aluminum mixed droplet area corresponding to the atmospheric plasma spray gun is circular. The square light spots of both the pre-treatment laser heating head and the post-treatment laser heating head are tangent to the nickel-aluminum mixed droplet area.
[0025] Preferably, the length of the square spot is greater than the diameter of the nickel-aluminum mixed droplet region, and the length of the square spot is 40mm-60mm, the width is 40mm-60mm, and the diameter of the nickel-aluminum mixed droplet region is 30mm-50mm.
[0026] In an optional embodiment, before depositing the coating, the electrode mesh is cleaned and sandblasted in sequence, and then protective clamps are installed on the pores and edges of the electrode mesh, followed by descaling, degreasing, cleaning and drying in sequence.
[0027] Preferably, the dried electrode mesh is fixed on a fixed stage before coating deposition, so that the electrode mesh remains in a fixed position during the coating deposition process.
[0028] Secondly, the present invention provides a cathode plate mesh for water electrolysis, which is prepared by any of the preparation methods described in the foregoing embodiments.
[0029] Thirdly, the present invention provides an electrolysis apparatus, including the cathode plate mesh for water electrolysis of the foregoing embodiments.
[0030] This invention has the following beneficial effects: by using atmospheric plasma spraying to spray molten nickel and aluminum droplets onto the heated electrode plate surface, the molten nickel and aluminum droplets on the heated electrode plate surface are more likely to diffuse, increasing the contact area between nickel / aluminum and nickel / nickel, and simultaneously allowing a large number of elements to diffuse and form a strong bond; heating the nickel-aluminum mixed coating on the coating surface promotes the bonding of the deposited particles at the interface, while also causing diffusion at the nickel-aluminum interface to form a nickel-aluminum alloy, thereby further enhancing the surface activity of the porous nickel coating after aluminum removal and activation.
[0031] The preparation method provided in this embodiment of the invention is used to prepare a catalytic nickel coating on the surface of the electrode plate mesh, which can create a porous nickel coating with high interfacial bonding strength and high activity, and can meet its requirements for efficient and stable service in the electrolytic cell. Attached Figure Description
[0032] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0033] Figure 1 A schematic diagram illustrating the process of preparing a high-purity, highly active porous catalyst layer on the surface of an electrode plate mesh in an electrolytic cell.
[0034] Figure 2 Microscopic morphology of the coating surface of the alkaline water electrolysis cathode electrode prepared by conventional plasma spraying process; in the figure, (b) is a partial magnification of (a);
[0035] Figure 3 Microscopic morphology of the coating surface of the alkaline water electrolysis cathode electrode prepared by the method of the present invention; in the figure, (b) is a partial magnification of (a). Detailed Implementation
[0036] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.
[0037] This invention provides a method for preparing a cathode plate mesh for water electrolysis, comprising:
[0038] S1, Preprocessing
[0039] Before depositing the coating, the electrode mesh is pretreated to remove impurities and clean the surface, which helps to improve the bonding effect between the coating and the electrode mesh.
[0040] In some embodiments, the pretreatment steps include: sequentially cleaning and sandblasting the electrode mesh, then assembling protective fixtures on the pores and edges of the electrode mesh, followed by sequentially removing dust, oil, cleaning, and drying. Sandblasting can improve surface roughness, which is beneficial to the bonding between the coating and the substrate. Removing dust and oil can achieve surface cleaning, which is beneficial to further improving the bonding effect of the coating.
[0041] It should be noted that in other embodiments, if the roughness and surface cleanliness of the electrode plate mesh meet the requirements, pretreatment may not be necessary.
[0042] In some embodiments, the dried electrode mesh is fixed on a fixed platform before coating deposition, so that the electrode mesh remains in a fixed position during the coating deposition process, thereby improving the stability of the device operation.
[0043] Specifically, the electrode mesh is made of high-purity nickel with a purity greater than 99.9%.
[0044] S2, Heating-Spraying-Reheating
[0045] First, the electrode plate mesh is heated to the required temperature. Then, molten nickel and aluminum droplets are sprayed onto the heated electrode plate mesh surface using atmospheric plasma spraying. This makes it easier for the heated electrode plate mesh surface and the molten nickel and aluminum droplets to diffuse and form a nickel-aluminum mixed coating. After the coating is formed, the nickel-aluminum mixed coating on the coating surface is heated to allow diffusion at the nickel-aluminum interface, forming a nickel-aluminum alloy. This further enhances the surface activity of the porous nickel coating after aluminum removal and activation.
[0046] In some embodiments, the surface of the electrode plate is heated to 200°C-300°C (preferably 250°C-280°C) using a pretreatment laser heating system before nickel and aluminum droplets are sprayed onto it. Similarly, a post-treatment laser is used to heat the nickel-aluminum mixed coating to 500°C-600°C (e.g., 500°C, 500°C, 530°C, 550°C, 580°C, 600°C, etc.). Laser heating is convenient to operate and easy to control. The power of the pretreatment laser heating system is 1KW-2KW, and the laser power of the post-treatment laser is controlled to be 4KW-6KW. It is preferable to control the power of both pretreatment and post-treatment laser heating within the above range to achieve the preset temperature more quickly.
[0047] Specifically, the temperature of the electrode plate surface heated by the pre-processing laser heating system can be 200℃, 230℃, 250℃, 280℃, 300℃, etc., and the power of the pre-processing laser heating system can be 1.0KW, 1.5KW, 2.0KW, etc.; the laser power of the post-processing laser can be 4.0KW, 4.5KW, 5.0KW, 5.5KW, 6.0KW, etc.
[0048] In some embodiments, please combine Figure 1Nickel and aluminum powders are used as raw materials, and are melted into nickel and aluminum droplets through atmospheric plasma spraying. The mass ratio of nickel to aluminum powder is 1:(0.2-0.3), such as 1:0.20, 1:0.23, 1:0.25, 1:0.28, 1:0.30, etc. The nickel and aluminum powders are mixed and heated to produce nickel and aluminum droplets. The ratio of nickel to aluminum powder within the above range is preferable to further improve the surface activity of the porous nickel coating. The particle size range of both nickel and aluminum powders is 45μm-78μm, and the purity of both is greater than 99.5%. The smaller particle size of nickel and aluminum powders is beneficial for forming a uniform coating; the higher purity of nickel and aluminum powders is beneficial for improving the purity of the coating.
[0049] Specifically, the particle size of nickel powder and aluminum powder can be the same or different, with a particle size of 45μm-78μm being preferable, such as 45μm, 50μm, 55μm, 60μm, 65μm, 70μm, 75μm, 78μm, etc.
[0050] Furthermore, the deposition rate of the molten nickel and aluminum droplets is less than 150 m / s; preferably, the deposition rate of the molten nickel and aluminum droplets is 50 m / s-80 m / s. The deposition rate of the nickel and aluminum droplets is preferably within the above range to reduce droplet splashing and improve interfacial bonding and deposition efficiency. Specifically, the deposition rate of the nickel and aluminum droplets can be 10 m / s, 30 m / s, 50 m / s, 60 m / s, 70 m / s, 80 m / s, 100 m / s, 120 m / s, 140 m / s, 145 m / s, etc.
[0051] like Figure 1 As shown, the pre-treatment laser heating head in the pre-treatment laser heating system heats the surface of the electrode plate mesh, and the post-treatment laser heating head heats the nickel-aluminum hybrid coating. The pre-treatment laser heating head, atmospheric plasma spray gun, and post-treatment laser heating head, arranged sequentially, are fixed on a movable slide rail, allowing them to move in unison along the same trajectory and at the same speed. After treatment by the atmospheric plasma spray gun, a conventional catalytic layer is formed. The post-treatment laser heating head irradiates the deposited nickel-aluminum hybrid coating area to form an optimized catalytic layer. This promotes the bonding of deposited particles at the interface and creates a diffusion layer at the interface of the nickel-aluminum hybrid coating, further enhancing the surface activity of the porous nickel coating after aluminum removal and activation. By assembling the pre-treatment laser heating head, atmospheric plasma spray gun, and post-treatment laser heating head, the spraying process can be more easily controlled, and the conditions in different areas of the coating can be better controlled, improving the uniformity of the coating.
[0052] Specifically, during the process, a pre-treatment laser heating head is first used to heat a portion of the electrode grid. Then, atmospheric plasma spraying is used to spray molten nickel and aluminum droplets into this area for deposition, forming a coating. The post-treatment laser heating head irradiates the already coated area to achieve nickel-aluminum diffusion. The high-frequency post-treatment laser heating head, linked with atmospheric plasma spraying, can irradiate the area of the old catalyst layer to be overlapped before a new round of deposition begins on the surface of the formed catalyst layer. This allows a diffusion layer to form at the interface of the nickel-aluminum mixed coating, thereby further enhancing the surface activity of the porous nickel coating after aluminum removal and activation.
[0053] In some embodiments, control Figure 1 The overall horizontal movement speed of the device is 500mm / s-1000mm / s, such as 500mm / s, 600mm / s, 700mm / s, 800mm / s, 900mm / s, 1000mm / s, etc. The spacing for atmospheric plasma spraying is 500mm-600mm (e.g., 500mm, 530mm, 550mm, 580mm, 600mm, etc.), referring to the distance between the spray gun and the electrode mesh. By controlling parameters such as spacing, movement speed, and heating temperature, the temperature of the heated electrode mesh can be further controlled, improving the bonding strength of the coating on the electrode mesh.
[0054] The atmospheric plasma spray gun can be controlled to move in a zigzag deposition path. When moving in the reverse direction, the roles and powers of the pre-processing laser heating head and the post-processing laser heating head are interchanged. That is, when moving in the reverse direction, the original pre-processing laser heating head becomes the post-processing laser heating head, and the original post-processing laser heating head becomes the pre-processing laser heating head.
[0055] like Figure 1 As shown, both the pre-processing and post-processing laser heating heads have square laser spots, as illustrated in the figure. The nickel-aluminum mixed droplet region corresponding to the atmospheric plasma spray gun is a circle with a diameter of D. The square laser spots of both the pre-processing and post-processing laser heating heads are tangent to the nickel-aluminum mixed droplet region. Figure 1 In the diagram, the circular plasma spraying area is tangent to the square laser spots on either side. During operation, the pretreatment laser heating head, atmospheric plasma spraying, and post-treatment laser heating head work simultaneously. For the same area, heating occurs first, followed by spraying, and finally, heating diffusion. The term "tangent" here refers to approximate tangency; a small gap may also exist. The post-treatment laser heating head overlaps with the short sides of the two square laser spots on the laser heating head, covering the overlap area between the old and new catalyst layers.
[0056] Furthermore, the length of the square spot is greater than the diameter of the nickel-aluminum mixed droplet region, i.e., L > D, and the length of the square spot is 40mm-60mm (e.g., 40mm, 50mm, 60mm, etc.), and the width is 40mm-60mm (e.g., 40mm, 50mm, 60mm, etc.), while the diameter of the nickel-aluminum mixed droplet region is 30mm-50mm (e.g., 30mm, 40mm, 50mm, etc.). By optimizing the dimensions of each region, temperature control is achieved more precisely, allowing the coating to adhere uniformly to the screen.
[0057] This invention provides a cathode plate mesh for water electrolysis, which is prepared by the above-described method. The nickel coating on the surface of the electrode plate mesh has a high bonding strength and can meet the requirements for long-term service at temperatures above 80°C.
[0058] This invention also provides an electrolysis device, including the above-mentioned cathode plate mesh for water electrolysis, and may also include an electrolysis cell, forming a complete water electrolysis device.
[0059] The features and performance of the present invention will be further described in detail below with reference to embodiments.
[0060] Example 1
[0061] This embodiment provides a method for preparing a cathode plate mesh for water electrolysis, including:
[0062] (1) Pretreatment: The surface of the electrode plate mesh (material is 40#, purity 99.9% pure nickel mesh) of the electrolytic cell is cleaned and sandblasted in sequence. Then, protective clamps are installed on the pores and edges of the electrode plate mesh. Then, the ash is removed, the oil is removed, cleaned and dried. The surface of the electrode plate mesh after treatment should be free of impurities. Finally, the electrode plate mesh is installed on the electrode plate mesh fixing platform and fixed to ensure that the electrode plate mesh does not move during the preparation of the catalyst layer.
[0063] (2) Figure 1 As shown, the pretreatment laser heating head, atmospheric plasma spray gun, and posttreatment laser heating head are fixed on a movable slide rail, and the three are linked together with the same movement trajectory and speed. When the catalytic layer on the electrode plate mesh surface is prepared, the nozzle movement path is a simple U-shaped deposition path. With the help of the movable slide rail, the solid-state atmospheric plasma spray can move at a uniform speed of 500 mm / s relative to the electrode plate mesh surface.
[0064] (3) A moving laser heating head, an atmospheric plasma spray gun, and a high-frequency post-processing laser heating head are used. Before powder deposition, the electrode mesh surface is heated by a laser heating system. Supersonic molten nickel and aluminum droplets ejected from the nozzle, with a nickel-aluminum powder volume ratio of 1:0.25, collide with the laser-heated electrode mesh surface. The molten nickel and aluminum droplets and the electrode mesh surface material are more likely to diffuse, increasing the contact bonding area. At the same time, a large number of elements diffuse, thus forming a strong bond. The pre- and post-processing laser heating heads are square spots with a side length of 50 mm, and the diameter of the nickel-aluminum mixed droplet area is 40 mm. The pre-processing laser heating head has a power of 2000 W, and the pre-processing laser heating system raises the temperature of the 50 mm square area on the electrode mesh surface to about 250 °C. Nickel and aluminum powders with a purity >99.5%, spherical shape, and an average particle size of 50 μm are melted by plasma spraying and accelerated to 80 m / s. After the molten nickel and aluminum droplets are successively deposited on the heated electrode plate mesh surface, a catalytic coating with a thickness of 50 μm is formed on the electrode plate mesh wall.
[0065] (4) Use a 6000W post-processing laser heating head to irradiate the surface of the formed catalyst layer. The surface of the catalyst layer is heated to about 550°C, so that a diffusion layer is formed at the interface of the nickel-aluminum mixed coating, which can further enhance the surface activity of the porous nickel coating after aluminum removal and activation.
[0066] The cathode plate mesh prepared in this embodiment was subjected to performance testing. The testing methods were: (1) physical folding; (2) precise weighing; and (3) electrochemical testing.
[0067] Testing revealed that when the catalytic coating was folded 90° and held in this position for more than 5 seconds, no coating peeling or substrate exposure occurred at the fold. Similarly, when folded 120° and held for more than 5 seconds, no coating peeling or substrate exposure occurred at the fold. When folded 180° and held for more than 5 seconds, no coating peeling or substrate exposure occurred at the fold. After activation with a 30wt% potassium hydroxide solution for 24 hours and followed by ultrasonication for 30 minutes, the coating weight loss was 15%. The hydrogen evolution current was 100 mA / cm². 2 The hydrogen evolution overpotential is 0.3V.
[0068] Comparative Example 1
[0069] The only difference between this comparative example and Example 1 is that the post-processing laser was not used to heat and diffuse the deposited catalyst layer; all other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.
[0070] The surface microstructure of the electrode coating prepared in this comparative example is as follows: Figure 2 As shown, the surface microstructure of the electrode coating prepared in Example 1 is as follows. Figure 3As shown in the figure, the results indicate that compared to Example 1, when the catalytic coating is folded at 90°, 120°, and 180°, there is no peeling or exposure of the substrate at the folds; after activation with 30wt% potassium hydroxide solution for 24 hours and ultrasonication for 30 minutes, the coating weight loss rate is 18%; the hydrogen evolution current is 100mA / cm. 2 The hydrogen evolution overpotential is 0.33V, which increases, indicating poor hydrogen evolution performance.
[0071] Comparative Example 2
[0072] The only difference between this comparative example and Example 1 is that a laser heating device is used, and the heating temperature of the electrode plate mesh surface is 600°C. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.
[0073] The results showed that, compared with Example 1, Comparative Example 2 had severe molten particle splashing, plate deformation, and could not obtain a uniform catalytic coating, resulting in unsatisfactory appearance.
[0074] Comparative Example 3
[0075] The only difference between this comparative example and Example 1 is that the collision deposition rate of the molten nickel droplets and aluminum droplets is 300 m / s. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.
[0076] The results showed that, compared with Example 1, Comparative Example 3 had severe molten particle splashing, making it impossible to obtain a uniform catalytic coating and failing the appearance inspection.
[0077] Comparative Example 4
[0078] The only difference between this comparative example and Example 1 is that the pretreatment laser heating device was not used, that is, the electrode plate was not heated before the coating was deposited. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.
[0079] The results showed that when the catalytic coating was folded at 90° and held in this position for more than 5 seconds, some coating peeled off at the fold, exposing 40% of the substrate. After activation with 30wt% potassium hydroxide solution for 24 hours and ultrasonication for 30 minutes, the coating weight loss rate was 36%. The hydrogen evolution current was 100 mA / cm². 2 The hydrogen evolution overpotential is 0.36V.
[0080] Comparative Example 5
[0081] The only difference between this comparative example and Example 1 is that nickel powder and aluminum powder with an average particle size of 350 μm are used. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.
[0082] The results showed that after the coating was activated by 30wt% potassium hydroxide solution for 24 hours and then sonicated for 30 minutes, the coating weight loss rate was 55%, which was significantly higher and the electrode stability was poor.
[0083] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing a cathode plate mesh for water electrolysis, characterized in that, include: Using atmospheric plasma spraying, molten nickel and aluminum droplets are sprayed onto the heated electrode plate mesh to form a nickel-aluminum mixed coating. The nickel-aluminum mixed coating is heated to form a nickel-aluminum alloy; The surface of the electrode plate is heated to 200℃-300℃ using a pretreatment laser heating system, and then the nickel droplets and aluminum droplets are sprayed on. The deposition rate of the molten nickel and aluminum droplets is less than 150 m / s; Nickel powder and aluminum powder are used as raw materials to melt into nickel droplets and aluminum droplets, wherein the mass ratio of nickel powder to aluminum powder is 1:(0.2-0.3), and the particle size range of both nickel powder and aluminum powder is 45μm-78μm; The nickel-aluminum hybrid coating is heated to 500℃-600℃ using a post-processing laser.
2. The preparation method according to claim 1, characterized in that, The deposition rate of the molten nickel and aluminum droplets is 50 m / s to 80 m / s.
3. The preparation method according to claim 2, characterized in that, The purity of both the nickel powder and the aluminum powder is greater than 99.5%.
4. The preparation method according to claim 1, characterized in that, The surface of the electrode plate is heated to 250°C-280°C using the pretreatment laser heating system.
5. The preparation method according to claim 1, characterized in that, The power of the pretreatment laser heating system is 1KW-2KW.
6. The preparation method according to claim 1, characterized in that, The laser power of the post-processing laser is controlled to be 4KW-6KW.
7. The preparation method according to claim 6, characterized in that, The surface of the electrode plate mesh is heated using a pre-processing laser heating head in a pre-processing laser heating system, and the nickel-aluminum mixed coating is heated using a post-processing laser heating head. The pretreatment laser heating head, atmospheric plasma spray gun, and posttreatment laser heating head, arranged sequentially, are fixed on a movable slide rail, so that the pretreatment laser heating head, atmospheric plasma spray gun, and posttreatment laser heating head move in tandem along the same trajectory and speed. The posttreatment laser heating head irradiates the deposited nickel-aluminum mixed coating area, and the overall horizontal movement speed is controlled to be 500mm / s-1000mm / s.
8. The preparation method according to claim 7, characterized in that, The spacing of the atmospheric plasma spraying is 500mm-600mm.
9. The preparation method according to claim 7, characterized in that, The atmospheric plasma spray gun is controlled to move in a U-shaped deposition path. When moving in the opposite direction, the roles and powers of the pre-processing laser heating head and the post-processing laser heating head are interchanged.
10. The preparation method according to claim 7, characterized in that, The laser spots of both the pre-treatment laser heating head and the post-treatment laser heating head are square laser spots. The nickel-aluminum mixed droplet area corresponding to the atmospheric plasma spray gun is circular. The square laser spots of both the pre-treatment laser heating head and the post-treatment laser heating head are tangent to the nickel-aluminum mixed droplet area.
11. The preparation method according to claim 10, characterized in that, The length of the square light spot is greater than the diameter of the nickel-aluminum mixed droplet region, and the length of the square light spot is 40mm-60mm and the width is 40mm-60mm, while the diameter of the nickel-aluminum mixed droplet region is 30mm-50mm.
12. The preparation method according to claim 1, characterized in that, Before the coating is deposited, the electrode mesh is cleaned and sandblasted in sequence. Then, protective fixtures are installed on the pores and edges of the electrode mesh, followed by dust removal, oil removal, cleaning and drying.
13. The preparation method according to claim 12, characterized in that, The dried electrode mesh is fixed on a fixed stage before coating deposition, so that the electrode mesh remains in a fixed position during the coating deposition process.
14. A cathode plate mesh for water electrolysis, characterized in that, It is prepared by the preparation method according to any one of claims 1-13.
15. An electrolysis apparatus, characterized in that, Includes the cathode plate mesh for water electrolysis as described in claim 14.