Alkaline electrolytic water hydrogen production equipment, diaphragm and preparation method

Abstract

The invention discloses a method for preparing an alkaline electrolytic water hydrogen production diaphragm, which comprises the following steps: dissolving a polymer matrix of the diaphragm in a solvent to obtain a polymer solution, and dispersing a hydrophilic inorganic filler and a pore-forming agent (also called as a pore-foaming agent) in the polymer solution to obtain slurry; and coating the slurry on the surface of a diaphragm base net, applying pressure to the slurry in the coating process to obtain a base material, and immersing the base material in a coagulating bath to obtain the diaphragm. The external gravity is applied to the coating process of the membrane casting solution before phase inversion (solidification), the content of the membrane casting solution on the surface of the base net can be increased, tight attachment of the membrane casting solution and the base net can be promoted, and therefore the interface bonding strength is enhanced, the problem of uneven structures such as holes caused by interface defects is avoided, the resistance can be reduced, and the strength can be improved.

Description

Technical Field

[0001] This invention relates to a water electrolysis hydrogen production technology, and more particularly to an alkaline water electrolysis hydrogen production device, a diaphragm, and a preparation method. Background Technology

[0002] Hydrogen is the most abundant substance in the universe, constituting 75% of its mass, and its reserves are plentiful. Hydrogen energy is considered the most promising clean energy source of the 21st century. With the increasing global emphasis on green economic development, the demand for and application of hydrogen energy are constantly expanding, making it a new focus of energy competition in the "global decarbonization era." Especially against the backdrop of accelerated progress towards global carbon neutrality goals, hydrogen energy, as a core carrier for achieving renewable energy consumption and deep decarbonization, is becoming increasingly strategically important. "Green hydrogen," produced through the electrolysis of water using renewable energy, has become the ultimate goal of hydrogen energy strategies for various countries due to its near-zero carbon emissions. my country's "dual-carbon" strategy positions the green hydrogen industry as a crucial pillar for national energy transformation and sustainable development.

[0003] Hydrogen production is a crucial link in the hydrogen energy industry chain. Based on production technology, it can be divided into fossil fuel-based hydrogen production, industrial by-product hydrogen production, and water electrolysis hydrogen production. Hydrogen energy can be categorized into three types based on its production source: "gray hydrogen," "blue hydrogen," and "green hydrogen." "Green hydrogen" is produced by electrolysis using renewable energy sources such as wind power, hydropower, solar (photovoltaic), and nuclear power. This process produces hydrogen with zero carbon emissions and yields high-purity hydrogen. However, the volatility and intermittency of renewable energy sources lead to significant power curtailment, posing a serious challenge to grid stability. For example, photovoltaic and wind power are significantly affected by weather conditions; statistics show that my country's annual wind and solar curtailment rate remains as high as 5%-15% during certain periods.

[0004] Converting surplus renewable energy into green hydrogen is a key path to solving the hydrogen production problem, and water electrolysis technology is the core component of this conversion process. Currently, global green hydrogen production accounts for less than 1% of total production, and behind this huge capacity gap, the efficiency, cost, and adaptability of electrolysis systems have become technological bottlenecks restricting industrial-scale development. As the core equipment for water electrolysis hydrogen production, the performance and cost of the electrolyzer directly determine the economic feasibility of green hydrogen, while the membrane, as a key component in the electrolyzer for isolating gases and conducting ions, requires technological innovation to significantly improve electrolysis efficiency.

[0005] Alkaline electrolyzers typically use KOH solution as the electrolyte and are suitable for large-scale engineering applications of water electrolysis for hydrogen production. Although alkaline water electrolysis technology has been commercialized, it is still plagued by problems such as low electrolysis current density, poor stability, and unsatisfactory electrolysis performance. To overcome these bottlenecks, current industrial alkaline water electrolyzers (AWE) generally employ porous composite membranes. Their structural design uses chemically inert polymers as a base to ensure alkali resistance and stability, and incorporates hydrophilic inorganic fillers to improve ion transport efficiency. Polysulfone (PSU) has become the mainstream substrate due to its high mechanical strength, excellent corrosion resistance, and high thermal stability. However, the inherent hydrophobicity of PSU (water contact angle > 85°C) severely limits its wettability in the electrolyte, directly leading to obstructed ion transport paths, increased surface resistivity, and increased hydrogen production energy consumption.

[0006] To overcome this bottleneck, researchers have introduced inorganic fillers to modify the membrane, enhancing its surface hydrophilicity, constructing ion channels to reduce surface resistivity, and improving OH- conductivity. However, the interfacial bonding strength between inorganic particles (ZrO2, TiO2, Al2O3, etc.) and the polymer matrix (polysulfone, polyetheretherketone, etc.) in the composite membrane, as well as the membrane surface smoothness, are key bottlenecks restricting its industrial application. Moreover, if the inorganic particle content is too low, the modification effect is limited; if the inorganic particle content is too high, it is easy to cause particle agglomeration, decreased interfacial bonding, and even powder shedding and cracking, which will damage the membrane performance and ultimately lead to a decrease in the physical and electrochemical properties of the membrane. This is detrimental to the operating efficiency and safety of the electrolyzer and may even cause gas permeation, leading to the risk of explosion. Summary of the Invention

[0007] This invention provides an alkaline water electrolysis hydrogen production membrane and its preparation method, as well as a water electrolysis hydrogen production device containing the membrane, to solve the problems mentioned in the above-mentioned technical background.

[0008] The first aspect of this application is to provide a method for preparing an alkaline water electrolysis hydrogen production membrane, comprising: The polymer matrix of the diaphragm is dissolved in a solvent to obtain a polymer solution. A slurry is obtained by dispersing a hydrophilic inorganic filler and a pore-forming agent (also known as a pore-forming agent) in the polymer solution; A slurry is coated onto the surface of a diaphragm substrate. Pressure is applied to the slurry during or after the coating process to obtain the substrate. The substrate is immersed in a coagulation bath to obtain the diaphragm.

[0009] In a preferred embodiment, the solvent may be one or more of alcohols, ethers, esters, carboxylic acids, ketones, aldehydes, amines, amides, phenols, aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons, heterocyclic compounds, sulfones, thioethers, and thiols.

[0010] In a preferred embodiment, the boiling point of the solvent is preferably ≥60℃, more preferably ≥80℃, more preferably ≥100℃, more preferably ≥120℃, more preferably ≥150℃, more preferably 80-300℃, and more preferably 100-250℃.

[0011] In a preferred embodiment, the solvent may contain or be selected from any one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, and dimethyl sulfoxide.

[0012] In a preferred embodiment, the polymer matrix may contain or be selected from any one or more of polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyphenylene sulfide, polyphenylene ethersulfone, polyoxazoline, polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, tetrafluoroethylene / hexafluoropropylene copolymer, perfluorosulfonic acid resin, polychlorotrifluoroethylene, and asbestos.

[0013] In a preferred embodiment, the weight ratio of the polymer matrix to the solvent is preferably 1:(1-10), more preferably 1:(2-9), even more preferably 1:(3-8), such as 1:4, 1:5, 1:6, 1:7.

[0014] In a preferred embodiment, the hydrophilic inorganic filler preferably contains or is selected from one or more of alumina, zirconium oxide, titanium dioxide, silicon dioxide, talc, mica, wollastonite, diatomaceous earth, kaolin, heavy calcium carbonate, feldspar, silica fume, zinc oxide, calcium carbonate, and aluminum hydroxide.

[0015] In a preferred embodiment, the weight ratio of the hydrophilic inorganic filler to the polymer matrix is ​​preferably 1:(0.1-10), more preferably 1:(0.5-9), even more preferably 1:(1-8), even more preferably 1:(2-7), such as 1:2, 1:3, 1:4, 1:5, 1:6, etc.

[0016] In a preferred embodiment, the pore-forming agent may be one or more of the following: β-cyclodextrin, polyethylene glycol, glycerin, polyvinylpyrrolidone, polyvinyl alcohol, silicone oil, sodium alginate, sucrose, hydroxypropyl cellulose, povidone, and polyurethane.

[0017] In a preferred embodiment, the weight ratio of the pore-forming agent to the polymer matrix is ​​preferably 1:(0.05-0.5), more preferably 1:(0.1-0.4), such as 1:0.2, 1:0.3, or 1:0.4.

[0018] In a preferred embodiment, "applying pressure to the slurry during or after coating" can be any one or more of the following methods: roller pressing, plate pressing, spot pressing.

[0019] For example, applying pressure to the slurry can be done by applying pressure to the coater during the coating process, thereby applying pressure to the slurry flowing out of the coater and contacting the surface of the diaphragm substrate.

[0020] For example, applying pressure to the slurry can be done by rollers applying pressure to the slurry applied to the diaphragm substrate after the coater during or after the coating process.

[0021] For example, applying pressure to the slurry can be done by a pressure plate applying pressure to the slurry applied to the diaphragm substrate after the coater during or after the coating process.

[0022] In a preferred embodiment, pressure can be applied to the coater, platen, or roller by loading a load.

[0023] Preferably, the load can be an object that provides additional weight, such as a weight or counterweight.

[0024] In a preferred embodiment, the pressure can be preferably ≥1N, more preferably ≥2N, more preferably ≥3N, more preferably 3-10N, such as 3-8N, for example 2N, 3N, 4N, 5N, 6N, 7N, etc.

[0025] In a preferred embodiment, the coagulation bath includes a first coagulation bath and a second coagulation bath. The substrate is successively immersed in the first coagulation bath and the second coagulation bath. The first coagulation bath and the second coagulation bath contain a liquid that can cause the polymer substrate to precipitate and solidify into a film. More preferably, the liquid may be one or more of the following: water, alcohol, ether, ester, carboxylic acid, ketone, aldehyde, phenol, amine, amide, halogenated hydrocarbon, aliphatic hydrocarbon, aromatic hydrocarbon, heterocyclic compound, and sulfoxide. For example, it may be one or more of the following: water, ethanol, isopropanol, n-propanol, methanol, diethyl ether, ethyl acetate, butyl acetate, glycerol, petroleum ether, acetic acid, formic acid, benzoic acid, acetone, formaldehyde, phenol, benzyl chloride, dichlorotoluene, chloroform, carbon tetrachloride, dioxane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, dimethyl sulfoxide, benzene, toluene, xylene, chlorobenzene, and N-methylpyrrolidone.

[0026] In a preferred embodiment, the residence time of the substrate in the first coagulation bath is preferably at least 5 minutes, more preferably 5-180 minutes, more preferably 10-150 minutes, more preferably 20-120 minutes, more preferably 30-100 minutes, and more preferably 40-90 minutes. For example, 50 minutes, 60 minutes, 70 minutes, 80 minutes, etc.

[0027] In a preferred embodiment, the residence time of the substrate in the second coagulation bath is preferably at least 5 minutes, more preferably 5-180 minutes, more preferably 10-150 minutes, more preferably 20-120 minutes, more preferably 30-100 minutes, and more preferably 40-90 minutes. For example, 50 minutes, 60 minutes, 70 minutes, 80 minutes, etc.

[0028] In a preferred embodiment, the slurry is degassed before being coated onto the surface of the diaphragm substrate. Preferably, the degassed treatment is performed under negative pressure; more preferably, the negative pressure is 0.1-10 × 10⁻⁶. -5 Pa, more preferably 0.5-8×10 -5 Pa, more preferably 1-5×10 Pa -5 Pa.

[0029] In a preferred embodiment, the degassing is carried out under heating conditions. Preferably, the heating temperature is at least 20°C, more preferably at least 30°C, more preferably 40-100°C, more preferably 45-80°C, and more preferably 50-75°C, such as 55°C, 60°C, 70°C, or 75°C.

[0030] An alkaline water electrolysis hydrogen production membrane, wherein the alkaline water electrolysis hydrogen production membrane is prepared by the above method.

[0031] An alkaline water electrolysis device includes an electrolysis cell with a positive electrode and a negative electrode inside. The alkaline water electrolysis hydrogen production membrane of the present invention is located between the positive electrode and the negative electrode.

[0032] This invention applies external gravity to the casting solution coating process before phase transformation (solidification), which helps to increase the content of casting solution on the substrate surface and promotes the tight adhesion between the casting solution and the substrate, thereby enhancing the interfacial bonding strength and avoiding structural unevenness problems such as pores caused by interfacial defects. This can reduce resistance and increase strength. Attached Figure Description

[0033] The accompanying drawings, which constitute a part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 These are SEM images of the diaphragm obtained in this invention; Figure 2 These are SEM images of the diaphragm obtained in the comparative analysis. Figure 3 This is a schematic diagram of the membrane preparation process of the present invention. Detailed Implementation

[0034] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be used interchangeably where appropriate. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or apparatuses.

[0036] Example 1: Refer to Figure 3 The method for preparing the diaphragm in this embodiment is as follows: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0037] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0038] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0039] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:1:0.3:4.

[0040] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 5N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0041] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0042] Example 2: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0043] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0044] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0045] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 7:1:0.5:5.

[0046] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 5N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0047] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0048] Example 3: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0049] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0050] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0051] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:2:0.5:5.

[0052] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 5N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0053] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0054] Example 4: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0055] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0056] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0057] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:2:0.5:5.

[0058] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 4N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0059] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0060] Example 5: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0061] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0062] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0063] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:2:0.5:5.

[0064] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 3N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0065] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0066] Example 6: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0067] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0068] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0069] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:2:0.5:5.

[0070] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A weight of 2N is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0071] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0072] Example 7: Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0073] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0074] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0075] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:2:0.5:5.

[0076] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 1N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0077] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0078] Comparative Example 1 Dissolve polysulfone in N-methylpyrrolidone and stir until homogeneous.

[0079] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0080] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0081] The weight ratio of N-methylpyrrolidone:polysulfone:polyvinylpyrrolidone:zirconium dioxide is 5:1:0.3:4.

[0082] At room temperature, the casting solution is uniformly coated onto the surface of the base mesh using a coating applicator with adjustable thickness to obtain the substrate. No additional external force is applied during the coating process.

[0083] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0084] Dissolve polyphenylene sulfide in N-methylpyrrolidone and stir until homogeneous.

[0085] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0086] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0087] The weight ratio of N-methylpyrrolidone:polyphenylene sulfide:polyvinylpyrrolidone:zirconium dioxide is 5:1:0.3:4.

[0088] At room temperature, the casting solution is uniformly coated (with a certain external force applied) onto the surface of the substrate using a coating applicator with adjustable thickness. A 5N weight is applied above the applicator to increase the gravity during the coating process, thereby obtaining the substrate.

[0089] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0090] Dissolve polyphenylene sulfide in N-methylpyrrolidone and stir until homogeneous.

[0091] Add polyvinylpyrrolidone and stir for 24 hours. Add zirconium dioxide and magnetically stir at 1000 rpm for 0.5 hours.

[0092] At a vacuum degree of 1×10 -5 Degassing was performed under conditions of Pa and 60℃ to obtain the casting solution.

[0093] The weight ratio of N-methylpyrrolidone:polyphenylene sulfide:polyvinylpyrrolidone:zirconium dioxide is 5:1:0.3:4.

[0094] At room temperature, the casting solution is uniformly coated onto the surface of the base mesh using a coating applicator with adjustable thickness to obtain the substrate. No additional external force is applied during the coating process.

[0095] The composite diaphragm can be obtained by immersing the coated substrate in the first coagulation bath and the second coagulation bath in sequence.

[0096] Table 1. Performance of the products obtained in this invention and comparative examples <![CDATA[Sheet resistance (Ω·cm 2 ).]]> Tensile strength (MPa) Alkali loss (%) Bubble pressure (bar) Example 1 0.21 24.4 0.23 2.55 Example 2 0.24 19.1 0.27 4.04 Example 3 0.27 20.9 0.31 6.73 Example 4 0.31 23.2 0.26 3.07 Example 5 0.29 21.7 0.30 3.54 Example 6 0.34 22.1 0.32 3.79 Example 7 0.32 20.3 0.29 5.03 Comparative Example 1 0.44 18.7 0.35 7.99 Example 8 0.29 20.7 0.28 4.96 Comparative Example 2 0.41 17.9 0.33 5.47 The test results from the above examples and comparative examples show that applying directional gravity during the coating preparation process of the alkaline water electrolysis hydrogen production membrane can significantly optimize the membrane performance. This method not only greatly improves the peel strength between the coating and the substrate, but also effectively reduces the sheet resistance and bubble point pressure of the membrane. As a result, the hydrogen production system can achieve higher electrolysis efficiency, lower energy consumption, and significantly enhanced operational safety and long-term stability.

[0097] contrast Figure 1 and Figure 2The characterization results of the membrane's microstructure show that the membrane in Example 1 has a microstructure with small and uniformly distributed pores; while the membrane in Comparative Example 1 exhibits larger pores and poorer uniformity. This structural difference will significantly affect the membrane's gas barrier performance. The larger pore size increases the risk of gas penetration, thus adversely affecting the operational safety of the hydrogen production system.

[0098] The specific embodiments of the present invention have been described in detail above, but they are merely examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications and substitutions to the present invention are also within the scope of the present invention. Therefore, all equivalent transformations and modifications made without departing from the spirit and scope of the present invention should be covered within the scope of the present invention.

Claims

1. A method for preparing an alkaline water electrolysis hydrogen production membrane, characterized in that, include: The polymer matrix of the diaphragm is dissolved in a solvent to obtain a polymer solution. A slurry is obtained by dispersing a hydrophilic inorganic filler and a pore-forming agent (also known as a pore-forming agent) in the polymer solution; The slurry is coated onto the surface of the diaphragm substrate. Pressure is applied to the slurry during the coating process to obtain the substrate. The substrate is immersed in a coagulation bath to obtain the diaphragm.

2. The method according to claim 1, characterized in that, The solvent has a boiling point of ≥60℃, more preferably ≥80℃, more preferably ≥100℃, more preferably ≥120℃, more preferably ≥150℃, more preferably 80-300℃, and more preferably 100-250℃.

3. The method according to claim 1 or 2, characterized in that, The solvent contains or is selected from any one or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, and dimethyl sulfoxide.

4. The method according to claim 1, characterized in that, The polymer matrix contains or is selected from any one or more of polysulfone, polyethersulfone, polyetherketone, polyetheretherketone, polyphenylene sulfide, polyphenylene ethersulfone, polyoxazoline, polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, tetrafluoroethylene / hexafluoropropylene copolymer, perfluorosulfonic acid resin, polychlorotrifluoroethylene, and asbestos; and / or The hydrophilic inorganic filler contains or is selected from one or more of the following: alumina, zirconium oxide, titanium dioxide, silicon dioxide, talc, mica, wollastonite, diatomaceous earth, kaolin, superphosphate, feldspar, silica fume, zinc oxide, calcium carbonate, and aluminum hydroxide; and / or The pore-forming agent may contain or be selected from one or more of β-cyclodextrin, polyethylene glycol, glycerin, polyvinylpyrrolidone, polyvinyl alcohol, silicone oil, sodium alginate, sucrose, hydroxypropyl cellulose, povidone, and polyurethane.

5. The method according to claim 1 or 4, characterized in that, The weight ratio of the polymer matrix to the solvent is preferably 1:(1-10), more preferably 1:(2-9), even more preferably 1:(3-8), such as 1:4, 1:5, 1:6, 1:7; and / or The weight ratio of the hydrophilic inorganic filler to the polymer matrix is ​​1:(0.1-10), more preferably 1:(0.5-9), even more preferably 1:(1-8), even more preferably 1:(2-7), such as 1:2, 1:3, 1:4, 1:5, 1:6; and / or The weight ratio of the pore-forming agent to the polymer matrix is ​​preferably 1:(0.05-0.5), more preferably 1:(0.1-0.4), such as 1:0.2, 1:0.3, 1:0.

4.

6. The method according to claim 1, characterized in that, The pressure is ≥1N, more preferably ≥2N, more preferably ≥3N, more preferably 3-10N, such as 3-8N, for example 2N, 3N, 4N, 5N, 6N, 7N.

7. The method according to claim 1 or 6, characterized in that, "Applying pressure to the slurry during the coating process" refers to any one or more methods such as roller pressing, plate pressing, and spot pressing.

8. The method according to claim 1, characterized in that, The coagulation bath includes a first coagulation bath and a second coagulation bath. The substrate is immersed in the first coagulation bath and the second coagulation bath successively. The first coagulation bath and the second coagulation bath contain a liquid that can cause the polymer substrate to precipitate and solidify into a film. More preferably, the liquid may be one or more of the following: water, alcohol, ether, ester, carboxylic acid, ketone, aldehyde, phenol, amine, amide, halogenated hydrocarbon, aliphatic hydrocarbon, aromatic hydrocarbon, heterocyclic compound, and sulfoxide. For example, it may be one or more of the following: water, ethanol, isopropanol, n-propanol, methanol, diethyl ether, ethyl acetate, butyl acetate, glycerol, petroleum ether, acetic acid, formic acid, benzoic acid, acetone, formaldehyde, phenol, benzyl chloride, dichlorotoluene, chloroform, carbon tetrachloride, dioxane, tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylformamide, dimethyl sulfoxide, benzene, toluene, xylene, chlorobenzene, and N-methylpyrrolidone. More preferably, the residence time of the substrate in the first coagulation bath and the second coagulation bath is independently at least 5 min, more preferably 5-180 min, more preferably 10-150 min, more preferably 20-120 min, more preferably 30-100 min, more preferably 40-90 min; for example 50 min, 60 min, 70 min, 80 min, etc.

9. An alkaline water electrolysis hydrogen production membrane prepared by the method of claim 1.

10. An alkaline water electrolysis device, comprising an electrolyzer, wherein a positive electrode and a negative electrode are provided in the electrolyzer, and the alkaline water electrolysis hydrogen production diaphragm as described in claim 1 or 9 is located between the positive electrode and the negative electrode.

Images