An electrolytic water anode plate mesh, its preparation method, and electrolysis device.

Abstract

This invention discloses an electrolytic water anode mesh, its preparation method, and an electrolysis apparatus, relating to the field of hydrogen production through water electrolysis. A collision-embedding method is used to deposit electrolytic nickel powder onto the surface of a preheated nickel mesh. By controlling the deposition conditions, a large-area, stable catalytic working layer with a micro / nano structure can be prepared, enhancing the electrolytic catalytic performance of the electrolysis. Compared to plasma spraying for Raney nickel deposition, the method provided by this invention eliminates the need for subsequent alkaline activation, significantly improving preparation efficiency and reducing equipment, maintenance, and manufacturing costs. Furthermore, it avoids the environmental pollution caused by alkaline aluminum removal activators. Compared to plasma spraying for Raney nickel deposition, the micro / nano dual-scale structure working layer prepared by this invention offers controllable micron and nanoscale dimensions and a three-dimensional structure, further enhancing the electrode's electrolytic catalytic performance and demonstrating excellent application prospects.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production technology, and more specifically, to an electrolytic water anode plate mesh, its preparation method, and an electrolysis device. Background Technology

[0002] With the gradual implementation of green and low-carbon energy development strategies and the existing need to control environmental pollution and reduce carbon emissions, the development of renewable energy is becoming increasingly vigorous, but this has also led to a serious problem of power curtailment. Utilizing water electrolysis to produce hydrogen is an effective way to convert, store, and reuse renewable energy, and can effectively promote the development of renewable energy.

[0003] Alkaline water electrolysis is a mature and safe method for hydrogen production, but its high energy consumption limits its application in the field of hydrogen production from surplus electricity. Nickel-based alloys, such as nickel-molybdenum alloys, nickel-molybdenum-sulfur alloys, and nickel-cobalt alloys, exhibit better catalytic hydrogen evolution activity than pure nickel. However, these alloys are unstable in strongly alkaline electrolytic solutions, leading to the dissolution of metal elements. This results in a gradual decrease in the catalytic hydrogen evolution performance of the electrode, and its catalytic performance deteriorates with long-term use.

[0004] Pure nickel porous coated electrodes are currently the electrode material used on a large scale in alkaline water electrolysis equipment. They are made by direct spraying of micron-sized nickel-aluminum mixed powder, with Al as the pore-forming agent. Before installation, the coating needs to be activated with an alkaline solution to prepare the porous electrode. However, this type of electrolysis has problems such as long production cycle, serious environmental pollution, and limited pore-forming capacity.

[0005] In summary, while existing mainstream plasma spraying methods have initially met the technical requirements for creating pores on the surface of pure nickel mesh, they still suffer from low catalytic performance. This is likely due to the limited pore-forming capacity of current preparation methods, resulting in poor interfacial bonding and activation stability of the products. There is an urgent need to prepare a pure nickel mesh with a micro / nano structured surface, eliminating the need for subsequent alkaline activation and further improving the electrode's electrolytic catalytic performance.

[0006] In view of this, the present invention is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide an electrolytic water anode plate mesh, its preparation method, and an electrolysis device, which aims to significantly improve the electrolytic catalytic performance of the electrode.

[0008] This invention is implemented as follows:

[0009] In a first aspect, the present invention provides a method for preparing an electrolytic water anode mesh, comprising: preheating a nickel mesh and then using a collision embedding method to deposit electrolytic nickel powder on the surface of the nickel mesh;

[0010] Among them, the collision embedding method uses high-pressure inert gas to accelerate electrolytic nickel powder through a nozzle, and the accelerated powder is embedded into the nickel plate mesh.

[0011] In an optional embodiment, the surface of the electrolytic nickel powder has protrusions of less than 5 μm, and the electrolytic nickel powder is dendritic.

[0012] Preferably, the average size of the electrolytic nickel powder is 5μm-120μm;

[0013] Preferably, the powder temperature is less than 100°C.

[0014] In an optional embodiment, the pressure of the high-pressure inert gas is 3MPa-10MPa, the gas temperature is less than 100℃, and the powder embedding speed is controlled to be 100m / s-500m / s.

[0015] Preferably, the high-pressure inert gas is unheated argon.

[0016] In an optional implementation, preheating involves heating the nickel plate mesh to a temperature of 500°C or higher.

[0017] Preferably, the preheating temperature is 500℃-600℃.

[0018] In an optional implementation, a high-frequency electromagnetic induction heating system is used to preheat the nickel plate mesh, and the operating frequency is controlled to be greater than 200Hz.

[0019] In an optional embodiment, the nickel plate mesh has a mesh count of 40-60.

[0020] In an optional embodiment, the nickel mesh is pretreated before depositing electrolytic nickel powder to make the roughness of the nickel mesh greater than 5 μm.

[0021] In an optional embodiment, the pretreatment includes: sandblasting the nickel mesh to achieve the required roughness, followed by cleaning and drying;

[0022] Preferably, the stencil tooling is protected before depositing electrolytic nickel powder;

[0023] Secondly, the present invention provides an electrolytic water anode plate mesh, which is prepared by any of the preparation methods described in the foregoing embodiments;

[0024] Preferably, the longitudinal deformation and compression of the deposited powder particles is <20%, and the embedding depth into the surface of the nickel plate mesh is >0.5μm;

[0025] Preferably, the coating on the nickel mesh has a bonding strength greater than 5 MPa with the mesh, and the coating thickness is 40 μm-100 μm.

[0026] Thirdly, the present invention provides an electrolysis apparatus, including the electrolytic water anode plate mesh of the aforementioned embodiments.

[0027] The present invention has the following beneficial effects: by using the collision embedding method, electrolytic nickel powder is deposited on the surface of the preheated nickel plate mesh. By controlling the deposition conditions, a catalytic working layer with micro-nano structure can be stably prepared over a large area, thereby improving the electrolytic catalytic performance of electrolysis.

[0028] Furthermore, compared to plasma spraying for Raney nickel deposition, the method provided by this invention can eliminate the subsequent alkaline activation step, significantly improving preparation efficiency and greatly reducing equipment, maintenance, and manufacturing costs, while eliminating environmental pollution caused by alkaline aluminum removal activators. Compared to plasma spraying for Raney nickel deposition, the micro-nano dual-scale working layer prepared by this invention has controllable micron and nano-scale dimensions and a three-dimensional structure, which can further improve the electrode electrolysis catalytic performance and has very good application prospects. Attached Figure Description

[0029] 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.

[0030] Figure 1 A schematic diagram illustrating the method for preparing a pure nickel plate mesh catalyst layer according to an embodiment of the present invention;

[0031] Figure 2 The image shows an electron microscope (EM) image of the electrolytic nickel powder used in the method of this embodiment of the invention.

[0032] Figure 3 This is a cross-sectional morphology diagram of the catalytic working layer formed by the method of this embodiment of the invention;

[0033] Figure 4 This is a surface morphology diagram of the catalytic working layer formed by the method of this embodiment of the invention;

[0034] Figure 5 This is a magnified partial view of the surface of the catalytic working layer formed by the method of this embodiment of the invention;

[0035] Figure 6 Electron micrograph of raw material (conventional gas-atomized nickel powder) used in conventional plasma methods;

[0036] Figure 7 This is a surface morphology diagram of the catalyst working layer formed by conventional plasma method;

[0037] Figure 8The image shows the morphology of dendritic electrolytic nickel powder in Comparative Example 4, where it melts completely or partially. Detailed Implementation

[0038] 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.

[0039] This invention provides a method for preparing an anode plate mesh for water electrolysis, comprising the following steps:

[0040] S1. Provides electrolytic nickel powder and nickel plate mesh.

[0041] like Figure 1 As shown, this embodiment of the invention uses dendritic electrolytic nickel powder, the surface of which has protrusions smaller than 5 μm. The inventors discovered that by using electrolytic nickel powder with this morphology as a raw material, micron-sized powder with a dendritic micro / nano structure can be directly deposited onto the surface of a plate mesh, thereby forming a catalytic layer with a micro / nano two-dimensional structure on the surface of the pure nickel plate mesh, thus improving the electrolytic catalytic performance of the electrode.

[0042] In some embodiments, the electrolytic nickel powder is pure nickel or nickel-based powder with a micro / nano two-dimensional structure. The average particle size of the electrolytic nickel powder is 5 μm-120 μm. Electrolytic nickel powder within this particle size range can produce a more uniform catalyst layer. Specifically, the average particle size of the electrolytic nickel powder can be 5 μm, 10 μm, 30 μm, 50 μm, 80 μm, 100 μm, 120 μm, etc.

[0043] Specifically, the electrolytic nickel powder can be commercially available materials, such as electrolytic nickel powder raw materials purchased from Changsha Tianjiu Metal Materials Co., Ltd.

[0044] In some embodiments, the mesh size of the nickel mesh is 40-60 mesh, such as 40 mesh or 60 mesh, which is more suitable for depositing the catalyst layer. The nickel mesh can be commercially available materials, such as 60# nickel mesh purchased from Jiangyin Nickel Mesh Factory Co., Ltd.

[0045] S2, Nickel Mesh Pretreatment

[0046] Before depositing electrolytic nickel powder, the nickel plate mesh is pretreated to make the roughness of the nickel plate mesh greater than 5μm, so as to further improve the bonding strength between the catalyst layer and the nickel plate mesh.

[0047] In some embodiments, the pretreatment includes: sandblasting the nickel mesh to achieve the required roughness, followed by cleaning and drying. Specifically, different sandblasting conditions can be used to sandblast the mesh surface to achieve a surface roughness greater than 5 μm. The cleaning reagent is not limited; organic reagents (such as acetone) can be used. The drying method is not limited; compressed gas can be used to dry the mesh surface, ensuring that the surface is free of impurities after pretreatment.

[0048] In some embodiments, the stencil is protected and clamped before depositing electrolytic nickel powder to prevent loosening during the deposition process.

[0049] S3, sedimentation

[0050] like Figure 1 As shown, after preheating the nickel mesh, an impact embedding method is used to deposit electrolytic nickel powder onto the surface of the nickel mesh. This invention bypasses the existing research approach of preparing pure nickel mesh with surface pores using ion-sprayed Raney nickel. Instead, it creatively utilizes a fully impact embedding method to directly plant micron-sized powder with a dendritic micro / nano structure onto the mesh surface, thereby forming a catalytic layer with a micro / nano two-dimensional structure on the pure nickel mesh surface, thus enhancing the electrolytic catalytic performance of the electrode.

[0051] In some embodiments, preheating involves induction heating of the nickel mesh to above 500°C, preferably 500°C-600°C. By controlling the preheating temperature, the electrolytic nickel powder deposited has a good bonding strength with the electrolytic nickel powder. Specifically, a high-frequency electromagnetic induction heating system can be used to preheat the surface of the activated area of ​​the nickel mesh, controlling the operating frequency to be greater than 200Hz, so that the nickel mesh can quickly reach the preset temperature.

[0052] Furthermore, collision embedding utilizes high-pressure inert gas to accelerate electrolytic nickel powder through a nozzle. The accelerated electrolytic nickel powder is then embedded into the nickel plate mesh, resulting in a catalyst layer with high bonding strength with the nickel plate mesh.

[0053] In some embodiments, the pressure of the high-pressure inert gas is 3MPa-10MPa, the gas temperature is less than 100℃, the powder embedding speed is controlled at 100m / s-500m / s, and the powder temperature is less than 100℃. By adjusting the collision embedding operation parameters, a uniform catalytic layer is formed after deposition, improving the catalytic performance of the electrode. When the powder is accelerated to the surface region, the dendritic electrolytic nickel powder will embed into the heated and softened surface of the plate mesh, uniformly forming a pure nickel coating with a micro-nano dual-scale structure. The activation specific surface area is greatly improved, and it has advantages such as high interfacial bonding strength, the activation layer is not easy to fall off, and stable electrolytic catalytic performance.

[0054] Specifically, the pressure of the high-pressure inert gas can be 3 MPa, 5 MPa, 8 MPa, 10 MPa, etc., and the gas temperature can be less than 100°C. It can be an unheated gas. "Powder embedding velocity" refers to the collision velocity of the powder after acceleration by the high-pressure inert gas. The powder embedding velocity after acceleration can be controlled to be 100 m / s, 200 m / s, 300 m / s, 400 m / s, 500 m / s, etc. The powder temperature is less than 100°C, and direct heating is not required during the deposition process. The high-pressure inert gas can be unheated argon, but is not limited to this.

[0055] This invention also provides an electrolytic water anode mesh, which is prepared by the above-described method. By forming a catalytic layer with a micro-nano two-dimensional structure on the surface of the pure nickel mesh, the electrolytic catalytic performance of the electrode is improved.

[0056] The thickness of the catalyst layer can be 40μm-100μm, such as 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, etc.

[0057] Testing revealed that the longitudinal deformation and compression of the deposited powder particles was less than 20%, indicating a relatively small deformation and compression. The embedding depth into the nickel mesh surface was greater than 0.5 μm, which is beneficial for improving the bonding strength between the coating and the mesh, resulting in a bonding strength greater than 5 MPa.

[0058] This invention also provides an electrolysis device, including the above-mentioned electrolytic water anode plate mesh, and may also include a cathode plate mesh, an electrolytic cell, etc., to form a complete electrolysis device.

[0059] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0060] It should be noted that the electrolytic nickel powder used in the following examples is a commercially available material, and the electron microscope image is shown below. Figure 2 As shown, the nickel powder exhibits a dendritic surface morphology with nanoscale protrusions on its surface.

[0061] Example 1

[0062] This embodiment provides a method for preparing an anode plate mesh for water electrolysis, the specific steps of which are as follows:

[0063] The surface of the 40-mesh nickel wire mesh is sandblasted to achieve a surface roughness greater than 5μm, then cleaned with acetone, and finally dried with compressed gas until the surface is free of impurities. The wire mesh fixture is then protected and securely clamped in place.

[0064] The surface of the activated area of ​​the plate mesh was preheated to 500℃ using a high-frequency electromagnetic induction heating system with a power of 5kW and a frequency of 200Hz. High-pressure argon gas was used to accelerate electrolytic nickel powder with an average size of 60 micrometers through a nozzle at a gas pressure of 3MPa and a gas temperature of 25℃. The accelerated powder velocity was 300m / s, and the deposition thickness was 50μm.

[0065] The morphology of the catalyst working layer prepared in this embodiment is shown in the figure below. Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, it can be seen that the dendritic electrolytic nickel powder is uniformly planted on the surface of the nickel plate mesh, forming numerous micron-sized pores, which effectively increases the specific surface area. At the same time, the surface of the electrolytic nickel powder contact also has a nano-sized protruding structure, which can significantly increase its contact area with media such as water, increase the reaction site, and improve catalytic performance.

[0066] Example 2

[0067] This embodiment provides a method for preparing an anode plate mesh for water electrolysis, the specific steps of which are as follows:

[0068] The surface of the 60-mesh nickel wire mesh is sandblasted to achieve a surface roughness greater than 5μm, then cleaned with acetone, and finally dried with compressed gas until the surface is free of impurities. The wire mesh fixture is then protected and securely clamped in place.

[0069] The surface of the activated area of ​​the plate mesh was preheated to 600℃ using a high-frequency electromagnetic induction heating system with a working power of 5kW and a frequency of 200Hz. Electrolytic nickel powder with an average size of 50μm was accelerated by high-pressure argon gas through a nozzle at a gas pressure of 3MPa and a gas temperature of 25℃. The accelerated powder velocity was 100m / s, and the deposition thickness was 35μm.

[0070] Example 3

[0071] This embodiment provides a method for preparing an anode plate mesh for water electrolysis, the specific steps of which are as follows:

[0072] The surface of the 60-mesh nickel wire mesh is sandblasted to achieve a surface roughness greater than 5μm, then cleaned with acetone, and finally dried with compressed gas until the surface is free of impurities. The wire mesh fixture is then protected and securely clamped in place.

[0073] The surface of the activated area of ​​the plate mesh was preheated to 600℃ using a high-frequency electromagnetic induction heating system with a power of 5kW and a frequency of 200Hz. High-pressure argon gas was used to accelerate electrolytic nickel powder with an average size of 120 micrometers through a nozzle at a pressure of 10MPa and a temperature of 25℃. The accelerated powder velocity was 500m / s, and the deposition thickness was 100μm.

[0074] Comparative Example 1

[0075] The surface of a 40-mesh nickel mesh is sandblasted to achieve a surface roughness greater than 5 μm, then cleaned with acetone, and finally dried with compressed gas until the surface is free of impurities. The mesh fixture is then protected and securely clamped in place. The activation area of ​​the mesh is preheated to 500°C using a high-frequency electromagnetic induction heating system (5 kW, 200 Hz). High-pressure argon gas is used to accelerate atomized spherical nickel powder with an average size of 60 μm through a nozzle (3 MPa, 25°C). The accelerated powder reaches a velocity of 300 m / s, resulting in a deposition thickness of 50 μm.

[0076] Taking Example 1 as an example, the only difference between this comparative example and Example 1 is that gas-atomized spherical nickel powder is used. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0077] The results showed that using traditional plasma spraying to atomize spherical powder could not form micro-nano scale structures on the surface of pure nickel mesh.

[0078] Specifically, the morphology diagram of the gas-atomized nickel powder used in the comparative example is as follows: Figure 6 As shown in the figure, the nickel powder is spherical or near-spherical. The morphology of the catalyst working layer prepared in this comparative example is shown in the figure. Figure 7 As shown, it can be seen that the powder melts significantly, forming a relatively dense nickel coating, and the contact area with water is significantly reduced.

[0079] Comparative Example 2

[0080] Taking Example 1 as an example, the only difference between this comparative example and Example 1 is that water atomization or fragmented irregular powder is used. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0081] The results showed that it was impossible to form micro-nano scale structures on the surface of pure nickel mesh.

[0082] Comparative Example 3

[0083] The only difference from Example 1 is that the pure nickel mesh was not preheated using an electromagnetic induction heating system; all other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0084] The results showed that the surface of the pure nickel mesh was not softened, and when the electrolytic powder impacted the mesh surface, it could not embed itself into the mesh, the powder could not be deposited, and a catalytic working layer could not be formed.

[0085] Comparative Example 4

[0086] The only difference between this comparative example and Example 1 is that the deposition method used is the traditional plasma spraying method (argon flow rate 60L / min, spraying power 50kw, hydrogen flow rate 20L / min, powder feeding rate 20g / min, spraying distance 100mm), and all other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0087] The results showed that dendritic electrolytic nickel powder would melt completely or partially. Figure 8 After material deposition, a conventional layered structure will be formed, making it impossible to form a co-working layer with micro-nano scale structures.

[0088] Comparative Example 5

[0089] The only difference between this comparative example and Example 1 is that the powder collision velocity is 1500 m / s. All other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0090] The results showed that dendritic electrolytic nickel powder would deform significantly, and the dendrites would compact and densify with each other, making it impossible to form a micro-nano scale co-working layer.

[0091] Comparative Example 6

[0092] The only difference between this comparative example and Example 1 is that the powder temperature is 600°C, while all other conditions (including structure, materials, parameters, etc.) are the same as in Example 1.

[0093] The results showed that the dendritic electrolytic nickel powder softened as a whole and deformed significantly after being sprayed onto the substrate surface. The dendrites compacted and densified each other, making it impossible to form a micro-nano scale co-working layer.

[0094] Experimental Example 1

[0095] The catalytic performance of the anode plates prepared in the test examples and comparative examples is shown in Table 1.

[0096] Test method: The oxygen evolution current was measured at 0.5 A / cm using an electrochemical workstation. 2 The oxygen evolution overpotential at that time.

[0097] Table 1. Oxygen evolution potential of anode mesh prepared in the examples and comparative examples @0.5 A / cm 2 OER overpotential

[0098]

[0099]

[0100] It is evident that the overpotential of the anode mesh prepared in the embodiments of the present invention is significantly lower.

[0101] 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 an electrolytic water anode plate mesh, characterized in that, include: After the nickel mesh is preheated, an impact embedding method is used to deposit electrolytic nickel powder on the surface of the nickel mesh. The collision embedding method utilizes high-pressure inert gas to accelerate the electrolytic nickel powder through a nozzle, and the accelerated powder then collides and embeds into the nickel plate mesh. The surface of the electrolytic nickel powder has protrusions smaller than 5 μm, and the electrolytic nickel powder is dendritic; the average size of the electrolytic nickel powder is 5 μm-120 μm, and the powder temperature is less than 100℃. The pressure of the high-pressure inert gas is 3MPa-10MPa, the gas temperature is less than 100℃, and the powder embedding speed is controlled to be 100m / s-500m / s. Before depositing the electrolytic nickel powder, the nickel plate mesh is pretreated to make the roughness of the nickel plate mesh greater than 5 μm.

2. The preparation method according to claim 1, characterized in that, The high-pressure inert gas is unheated argon.

3. The preparation method according to claim 1, characterized in that, The preheating involves heating the nickel plate mesh to a temperature of 500°C or higher.

4. The preparation method according to claim 3, characterized in that, The preheating temperature is 500℃-600℃.

5. The preparation method according to claim 4, characterized in that, The nickel plate mesh is preheated using a high-frequency electromagnetic induction heating system, with the operating frequency controlled to be greater than 200Hz.

6. The preparation method according to claim 1, characterized in that, The nickel plate mesh has a mesh count of 40-60.

7. The preparation method according to claim 1, characterized in that, The pretreatment includes: sandblasting the nickel plate mesh to achieve the required roughness, followed by cleaning and drying.

8. The preparation method according to claim 7, characterized in that, The stencil tooling is protected before the electrolytic nickel powder is deposited.

9. A water electrolysis anode plate mesh, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

10. The electrolytic water anode plate mesh according to claim 9, characterized in that, The longitudinal deformation and compression of the deposited powder particles is <20%, and the depth of embedding into the surface of the nickel plate mesh is >0.5μm.

11. The electrolytic water anode plate mesh according to claim 9, characterized in that, The coating on the nickel plate mesh has a bonding strength greater than 5 MPa with the plate mesh, and the coating thickness is 40 μm-100 μm.

12. An electrolysis apparatus, characterized in that, Includes the electrolytic water anode plate mesh according to any one of claims 9-11.

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