Catalyst layer, electrode, membrane electrode assembly, electrolytic device, and electrolytic process

Abstract

This application provides a catalyst layer, an electrode, a membrane electrode assembly, an electrolysis device, and an electrolysis process. The catalyst layer is made of a catalyst and a binder. The binder includes a main chain structure and modified groups directly attached to the main chain structure. The modified groups include cationic hydrophilic groups and non-cationic groups. The non-cationic groups are selected from at least one of sulfonic acid groups, phosphate groups, phosphonic acid groups, hydroxyl groups, carboxyl groups, amino groups, cyano groups, halogen groups, alkyl groups, haloalkyl groups, alkoxy groups, and heteroaryl groups. The catalyst layer can firmly bind water molecules and has a suitable hydrophilic-hydrophobic balance, improving the water retention and interfacial properties of the catalyst layer, thereby enhancing the performance of the catalyst layer, the membrane electrode assembly, and the electrolysis device.

Description

Technical Field

[0001] This application relates to the field of electrolysis technology, specifically to catalyst layers, electrodes, membrane electrode assemblies, electrolysis devices, and electrolysis processes. Background Technology

[0002] Anion exchange membrane electrolysis (AEMWE) is a novel hydrogen production technology that combines the low cost of alkaline water electrolysis with the high current density of proton exchange membrane water electrolysis. In related technologies, to simplify the system and reduce costs, a single-sided electrolyte inlet method is often adopted. This leads to difficulties in replenishing the liquid on the drying side, and the interface between the anion exchange membrane and the catalyst layer on the drying side is prone to dehydration, resulting in a sharp increase in ion conduction impedance, a decrease in catalyst activity, and severely impairing the long-term operational stability and durability of the electrolysis unit. Furthermore, good wetting of the catalyst layer at the anion exchange membrane interface and ion conduction of the membrane electrode assembly are crucial to the performance and stability of the electrolysis unit. Therefore, further improvements to the catalyst layer are needed to enhance the performance of the electrolysis unit. Summary of the Invention

[0003] In view of this, this application provides a catalyst layer, an electrode, a membrane electrode assembly, an electrolysis device, and an electrolysis process.

[0004] In a first aspect, this application provides a catalyst layer, the catalyst layer being made of a catalyst and a binder, the binder comprising a main chain structure and modified groups directly attached to the main chain structure, the modified groups comprising cationic hydrophilic groups and non-cationic groups, the non-cationic groups being selected from at least one of sulfonic acid groups, phosphate groups, phosphonic acid groups, hydroxyl groups, carboxyl groups, amino groups, cyano groups, halogen groups, alkyl groups, haloalkyl groups, alkoxy groups, and heteroaryl groups.

[0005] Optionally, in the adhesive, the molar ratio of the non-cationic group to the cationic hydrophilic group is 0.1%-10%.

[0006] Optionally, the cationic hydrophilic group includes at least one selected from quaternary ammonium cation, piperidinium cation, imidazolium cation, pyrrolidineium cation, quaternary phosphonium cation, guanidineium cation, quinine ring cation, and triazineium cation.

[0007] Optionally, the main chain structure is selected from at least one of polysulfone, polyphenylene ether, polyarylpiperidine, polyarylquinine, polynorbornene, polystyrene, polybenzimidazole, styrene-butadiene block copolymer and polyethylene.

[0008] Optionally, the number average molecular weight of the adhesive is 10 million to 1 million.

[0009] Optionally, the static water contact angle of the catalyst layer is less than or equal to 90°.

[0010] Optionally, the mass content of the binder in the catalyst layer is 2%-50%.

[0011] Optionally, the ion exchange capacity of the binder is 1.5 mmol / g to 3.5 mmol / g.

[0012] Optionally, the thickness of the catalyst layer is 3μm-40μm.

[0013] Optionally, the catalyst may be made of at least one metallic element selected from Ni, Fe, Co, Mn, Cu, Zn, Al, V, Cr, Mo, Ru, Au, Ag, Ir, Rh, Pd, Pt, and Re.

[0014] Secondly, this application provides an electrode comprising the catalyst layer and gas diffusion layer described in the first aspect.

[0015] Thirdly, this application provides a membrane electrode assembly, comprising a cathode gas diffusion layer, a cathode catalyst layer, an anion exchange membrane, an anode catalyst layer, and an anode gas diffusion layer stacked sequentially, wherein at least one of the cathode catalyst layer and the anode catalyst layer is selected from the catalyst layer described in the first aspect.

[0016] Optionally, the ion exchange capacity of the anion exchange membrane is 1.5 mmol / g to 3.5 mmol / g.

[0017] Optionally, the thickness of the anion exchange membrane is 20 μm-300 μm.

[0018] Optionally, the cathode catalyst layer is coated on the cathode gas diffusion layer or the anion exchange membrane; and / or, the anode catalyst layer is coated on the anode gas diffusion layer or the anion exchange membrane.

[0019] Fourthly, this application provides an electrolysis apparatus, including the membrane electrode assembly described in the third aspect.

[0020] Optionally, during electrolysis, the electrolysis device introduces electrolyte into the side of the cathode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the side of the anode catalyst layer facing away from the anion exchange membrane is not introduced with electrolyte; or during electrolysis, the electrolysis device introduces electrolyte into the side of the anode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the side of the cathode catalyst layer facing away from the anion exchange membrane is not introduced with electrolyte.

[0021] Fifthly, this application provides an electrolysis process in which an electrolyte is introduced into the electrolysis apparatus described in the fourth aspect, and a voltage is applied to the cathode catalyst layer and the anode catalyst layer in the electrolysis apparatus to perform electrolysis.

[0022] Optionally, the electrolyte is introduced into one side of the cathode catalyst layer, and the anode catalyst layer is selected from the catalyst layers described in the first aspect; or, the electrolyte is introduced into one side of the anode catalyst layer, and the cathode catalyst layer is selected from the catalyst layers described in the first aspect.

[0023] Optionally, the electrolyte is an aqueous solution containing an electrolyte, wherein the electrolyte includes at least one selected from KOH, NaOH, LiOH, K2CO3, KHCO3, Na2CO3, and NaHCO3, and the concentration of the electrolyte in the electrolyte is 0-7 mol / L.

[0024] Optionally, the electrolysis temperature is 25℃-85℃.

[0025] This application provides a binder in the catalyst layer that can interact with water molecules through cationic hydrophilic groups, enabling the catalyst layer to firmly bind water molecules. It can also adjust the hydrophilic-hydrophobic balance of the catalyst layer through non-cationic groups, thereby improving the water retention performance of the catalyst layer, reducing the interfacial resistance, and obtaining catalyst layers, electrodes and membrane electrode assemblies with excellent interfacial stability, good performance and long service life, thus improving the performance and service life of the electrolysis device. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. The specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0027] Figure 1 This is a cross-sectional schematic diagram of an electrode provided in one embodiment of this application.

[0028] Figure 2 This is a cross-sectional schematic diagram of a membrane electrode assembly provided in one embodiment of this application.

[0029] Figure 3 This is a schematic diagram of an electrolysis apparatus provided in one embodiment of this application.

[0030] Figure 4 This is a schematic diagram of the operation of an electrolysis apparatus provided in one embodiment of this application.

[0031] Figure 5 This is a schematic diagram of the operation of an electrolysis apparatus provided in another embodiment of this application.

[0032] Label Explanation: Catalyst layer-10, gas diffusion layer-20, electrode-100, cathode gas diffusion layer-201, cathode catalyst layer-202, anode gas diffusion layer-301, anode catalyst layer-302, anion exchange membrane-400, cathode chamber-200, anode chamber-300, membrane electrode assembly-500, electrolysis device-600. Detailed Implementation

[0033] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0034] This application provides a catalyst layer, the catalyst layer material comprising a catalyst and a binder. The binder includes a main chain structure and modified groups directly attached to the main chain structure. The modified groups include cationic hydrophilic groups and non-cationic groups. The non-cationic groups are selected from at least one of sulfonic acid groups, phosphate groups, phosphonic acid groups, hydroxyl groups, carboxyl groups, amino groups, cyano groups, halogen groups, alkyl groups, haloalkyl groups, alkoxy groups, and heteroaryl groups. The cationic hydrophilic groups in the binder can generate strong electrostatic interactions or hydrogen bonds with water molecules, enabling the catalyst layer to firmly bind a large number of water molecules, improving the water retention performance of the catalyst layer, especially its water retention capacity under low humidity and high temperature conditions, preventing problems such as drying, damage, and detachment of the catalyst layer. At the same time, the binder contains specific non-cationic groups, which can regulate the hydrophilic-hydrophobic balance of the catalyst layer. This is beneficial for the formation of an interconnected hydrophilic nanochannel network through microphase separation, storing and transporting water, achieving water redistribution and dynamic equilibrium, reducing interfacial resistance, and ensuring the structural stability and mechanical properties of the catalyst layer. Thus, a catalyst layer with excellent interfacial stability, good performance, and long service life is obtained.

[0035] The binder in the catalyst layer of this application is a hydrophilic binder, which not only serves as a binder to ensure the performance of the catalyst layer, but also improves the water retention capacity and uniform moisture distribution of the catalyst layer through its own modified groups, thereby enhancing the stability of the catalyst layer interface. This is beneficial for the use of the catalyst layer, electrodes, and membrane electrode assembly in electrolysis devices with a single-sided liquid feeding method, thus improving the performance of the electrolysis device. In some embodiments of this application, the modified groups are chemically bonded to the main chain structure.

[0036] In some embodiments of this application, the cationic hydrophilic group includes at least one selected from quaternary ammonium cations, piperidinium cations, imidazolium cations, pyrrolidineium cations, quaternary phosphonium cations, guanidinium cations, quinine ring cations, and triazineium cations. Quaternary ammonium cations exhibit strong binding forces with water molecules, further enhancing the water retention capacity of the catalyst layer; piperidinium cations, imidazolium cations, pyrrolidineium cations, quaternary phosphonium cations, guanidinium cations, quinine ring cations, and triazineium cations possess excellent alkaline stability, which is beneficial for providing OH- to the catalyst layer while simultaneously achieving water retention. - Transport channel. In some embodiments, the cationic hydrophilic group includes at least one selected from piperidinium cation, imidazolium cation, pyrrolidineonium cation, quaternary phosphonium cation, guanidineonium cation, quinine ring cation, and triazineonium cation, as well as a quaternary ammonium cation. This allows the quaternary ammonium cation to bind water molecules while also leveraging the excellent basic stability of the piperidinium cation, imidazolium cation, pyrrolidineonium cation, quaternary phosphonium cation, guanidineonium cation, quinine ring cation, and / or triazineonium cation, thereby further improving the reliability of the catalyst layer. In some embodiments, when the catalyst layer is an anode catalyst layer, the cationic hydrophilic group may include at least one selected from piperidinium cation, imidazolium cation, pyrrolidineonium cation, and quaternary phosphonium cation. In some embodiments, when the catalyst layer is an anode catalyst layer, the cationic hydrophilic group may include at least one selected from piperidinium cation, imidazolium cation, pyrrolidineonium cation, and quaternary phosphonium cation, as well as a quaternary ammonium cation. In some embodiments, when the catalyst layer is a cathode catalyst layer, the cationic hydrophilic group may include at least one of quaternary ammonium cations and imidazolonium cations.

[0037] The non-cationic groups of the binder in the catalyst layer of this application are selected from at least one of sulfonic acid groups, phosphoric acid groups, phosphonic acid groups, hydroxyl groups, carboxyl groups, amino groups, cyano groups, halogens (e.g., F, Cl, Br, I, etc.), alkyl groups, haloalkyl groups, alkoxy groups, and heteroaryl groups. These groups can regulate the hydrophilic-hydrophobic balance, avoid excessive swelling, and ensure the exhaust of gas in the hydrophobic channels, thereby facilitating the use of the catalyst layer. Among these, sulfonic acid groups, phosphoric acid groups, and phosphonic acid groups are anionic groups, while hydroxyl, carboxyl, amino, cyano, halogen, alkyl, haloalkyl, alkoxy, and heteroaryl groups are nonionic groups. That is, the non-cationic groups are non-cationic under alkaline conditions, and the non-cationic groups are selected from anionic groups and / or nonionic groups. Anionic groups can enhance electrostatic attraction with positively charged catalyst surfaces (such as NiFe-LDH) or metal oxides, improving the binding force between the binder and the catalyst. The electrostatic interaction between anionic and cationic groups helps to form clearer hydrophilic / hydrophobic nanochannels. Nonionic groups can regulate the hydrophilic-hydrophobic balance, enhance the inter-chain forces of the binder polymer, avoid excessive swelling, inhibit excessive water absorption and swelling caused by high ion exchange capacity, improve mechanical stability, and ensure the discharge of gas in the hydrophobic channels, thus benefiting the use of catalyst layers, electrodes and membrane electrode assemblies.

[0038] In this application, the alkyl group is a chain alkyl group, which can be a straight-chain alkyl group or a branched alkyl group. In the embodiments of this application, the number of carbon atoms in the alkyl group can be 1-10. For example, the number of carbon atoms in the alkyl group can be, but is not limited to, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. Specifically, the alkyl group can be, but is not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 2,2-dimethylheptyl, 4-methylhexyl, etc. In this application, the haloalkyl group is an alkyl group substituted with a halogen (F, Cl, Br, I, etc.); at least one hydrogen atom in the alkyl group is substituted with a halogen. For example, 1, 2, 3, 4, 5, 6, or 7 hydrogen atoms in the alkyl group are substituted with the same halogen or different halogens. In this application, the heteroaryl group is an aryl group having at least one heteroatom (oxygen, sulfur, nitrogen, etc.). For example, the number of carbon atoms in a heteroaryl group can be, but is not limited to, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, or 15.

[0039] In some embodiments of this application, the molar ratio of non-cationic groups to cationic hydrophilic groups in the binder is 0.1%-10%. The binder has a relatively large number of cationic hydrophilic groups and a relatively small number of non-cationic groups, allowing the cationic hydrophilic groups to exert a strong hydrophilic and water-retaining effect, while the non-cationic groups assist in the hydrophilic-hydrophobic balance of the catalyst layer, further optimizing the interfacial performance of the catalyst layer. For example, the molar percentage of non-cationic groups to cationic hydrophilic groups in the binder can be, but is not limited to, 0.1%, 0.3%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.7%, 2%, 2.4%, 2.5%, 2.8%, 3%, 3.5%, 3.6%, 4%, 4.2%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10%, etc.

[0040] Modifying groups in the binder are used to improve the binder's performance and enhance the interfacial properties of the catalyst layer and electrode. The main chain structure in the binder ensures the binder's basic bonding performance, mechanical properties, and reliability. In some embodiments of this application, the main chain structure is selected from at least one of polysulfone, polyphenylene ether, polyarylpiperidine, polyarylquinine, polynorbornene, polystyrene, polybenzimidazole, styrene-butadiene block copolymer, and polyethylene. That is, the binder can be selected from at least one of the following: modified polysulfone, modified polyphenylene ether, modified polyarylpiperidine, modified polyarylquinine, modified polynorbornene, modified polystyrene, modified polybenzimidazole, modified styrene-butadiene block copolymer, and modified polyethylene. Polysulfone, polyphenylene ether, polyarylpiperidine, polynorbornene, polystyrene, styrene-butadiene block copolymers, and polyethylene can interact with cationic hydrophilic groups, resulting in microphase separation to form a network of hydrophilic channels for storing and transporting moisture, as well as pathways for transporting gases. This can further optimize the interfacial properties of the catalyst layer and improve its performance. Polyaryl quinine and polybenzimidazole have excellent hydrophilic properties, which are beneficial for further improving the catalyst layer's ability to store and transport moisture, and further enhancing its water retention performance. This is advantageous for use in electrolysis devices with single-sided liquid inlet.

[0041] In some embodiments of this application, the ion exchange capacity of the binder is 1.5 mmol / g-3.5 mmol / g to ensure the ion conductivity of the catalyst layer. Exemplarily, the ion exchange capacity of the binder may be, but is not limited to, 1.5 mmol / g, 1.6 mmol / g, 1.7 mmol / g, 1.8 mmol / g, 1.9 mmol / g, 2 mmol / g, 2.1 mmol / g, 2.2 mmol / g, 2.3 mmol / g, 2.4 mmol / g, 2.5 mmol / g, 2.6 mmol / g, 2.7 mmol / g, 2.8 mmol / g, 2.9 mmol / g, 3 mmol / g, 3.1 mmol / g, 3.2 mmol / g, 3.3 mmol / g, 3.4 mmol / g, or 3.5 mmol / g. In this application, the ion exchange capacity is determined by the 7th point titration method according to the T / CRES0028-2025 standard.

[0042] In some embodiments of this application, the number-average molecular weight of the adhesive is 10 million to 1 million, which is beneficial to the bonding and water-retention properties. For example, the number-average molecular weight of the adhesive may be, but is not limited to, 1000, 5000, 10,000, 30,000, 50,000, 100,000, 150,000, 180,000, 200,000, 250,000, 300,000, 350,000, 400,000, 450,000, 500,000, 550,000, 600,000, 650,000, 700,000, 750,000, 800,000, 850,000, 900,000, 950,000, or 1 million.

[0043] In some embodiments of this application, the static water contact angle of the catalyst layer is less than or equal to 90°. That is, the surface of the catalyst layer is a hydrophilic surface, which is beneficial for the adhesion and distribution of water molecules. In this application, a contact angle meter is used to detect the static water contact angle of the catalyst layer. Exemplarily, the static water contact angle of the catalyst layer can be, but is not limited to, 2°, 5°, 10°, 12°, 15°, 18°, 20°, 25°, 27°, 30°, 35°, 38°, 40°, 43°, 45°, 50°, 55°, 60°, 65°, 68°, 70°, 75°, 80°, 83°, 85°, 88°, or 90°. In some embodiments, the static water contact angle of the catalyst layer can be 2°-80°.

[0044] In some embodiments of this application, the binder content in the catalyst layer is 2%-50% by mass. This not only helps ensure stable adhesion of the catalyst and the effective function of the catalyst layer, but also enhances the water retention capacity of the catalyst layer, thereby improving its performance and durability. For example, the binder content in the catalyst layer can be, but is not limited to, 2%, 5%, 8%, 10%, 13%, 15%, 17%, 20%, 22%, 25%, 28%, 30%, 34%, 35%, 37%, 40%, 41%, 45%, 47%, or 50%.

[0045] The catalyst is used to catalyze the electrolysis reaction. In some embodiments of this application, the mass content of the catalyst in the catalyst layer is 50%-98%, which is beneficial to the electrolysis reaction. Exemplarily, the mass content of the catalyst in the catalyst layer may be, but is not limited to, 50%, 55%, 58%, 60%, 65%, 67%, 70%, 72%, 75%, 80%, 83%, 85%, 88%, 90%, 93%, 95%, 96%, or 98%, etc.

[0046] Understandably, the catalyst layer can serve as the anode catalyst layer or the cathode catalyst layer in an electrolysis device. In some embodiments of this application, the catalyst material includes at least one metallic element selected from Ni, Fe, Co, Mn, Cu, Zn, Al, V, Cr, Mo, Ru, Au, Ag, Ir, Rh, Pd, Pt, and Re. Exemplarily, the catalyst can be selected from at least one of the following: elemental form, alloy, oxide, hydroxide, layered double hydroxide, sulfide, phosphide, selenide, heteroatom-doped carbon material, metal / carbon, and metal / heteroatom-doped carbon; heteroatoms can be, but are not limited to, N, B, S, P, etc. In heteroatom-doped carbon materials, metal atoms are coordinated with heteroatoms and embedded in carbon groups; heteroatom-doped carbon materials can include heteroatom-doped carbon materials containing metallic elements (including metal-nitrogen-carbon) and non-metallic heteroatom-doped carbon materials. Metal / carbon is a composite of metal particles (nanoparticles, nanowires, etc.) and carbon materials (such as carbon black, graphene). Metal / heteroatom-doped carbon consists of metal particles supported on a heteroatom-doped carbon substrate. The catalyst can be an alloy containing at least one of the aforementioned metal elements; for example, the catalyst can be selected from nickel-iron-based layered double hydroxides (NiFe-LDH). Alternatively, the catalyst can be selected from platinum-supported carbon (Pt / C). In some embodiments, the mass content of platinum in the platinum-supported carbon can be 20%-60%. Exemplary examples include, but are not limited to, 20%, 30%, 40%, 50%, or 60% of the platinum in the platinum-supported carbon.

[0047] In some embodiments of this application, the thickness of the catalyst layer is 3μm-40μm, which is beneficial for the effective functioning of the catalyst and binder without excessively increasing the thickness and weight of the catalyst layer. Exemplarily, the thickness of the catalyst layer can be, but is not limited to, 3μm, 5μm, 7μm, 8μm, 10μm, 12μm, 15μm, 17μm, 20μm, 22μm, 25μm, 28μm, 30μm, 33μm, 35μm, 37μm, 38μm, or 40μm.

[0048] Please see Figure 1 This is a cross-sectional schematic diagram of an electrode provided in one embodiment of this application. The electrode 100 includes the catalyst layer 10 and the gas diffusion layer 20 in any of the above embodiments.

[0049] A catalyst layer can be disposed on the surface of a gas diffusion layer. The gas diffusion layer serves to support the catalyst layer and also facilitates gas diffusion and transport, ensuring electrolysis. The gas diffusion layer can have a porous structure to facilitate gas transport and diffusion. In some embodiments of this application, when the electrode is the anode of the electrolysis device, the material of the gas diffusion layer can be selected from at least one of elemental nickel, nickel alloys, and stainless steel. Nickel alloys can take the form of fiber felt, powder felt, foam, composite mesh felt, etc. In some embodiments of this application, when the electrode is the cathode of the electrolysis device, the material of the gas diffusion layer can be selected from at least one of carbon materials, elemental nickel, nickel alloys, and stainless steel. For example, carbon materials can take the form of carbon cloth, carbon paper, carbon felt, etc., and nickel alloys can take the form of fiber felt, powder felt, foam, composite mesh felt, etc.

[0050] In some embodiments of this application, the thickness of the gas diffusion layer is 0.1 mm to 3 mm. For example, the thickness of the gas diffusion layer may be, but is not limited to, 0.1 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, or 3 mm.

[0051] This application also provides a method for preparing an electrode, comprising: mixing a catalyst, a binder, and a solvent to form a mixture; coating the mixture onto the surface of a gas diffusion layer; and drying to form a catalyst layer, thereby obtaining an electrode. The coating can be, but is not limited to, applying the mixture to the surface of the gas diffusion layer by methods such as coating (spraying, roller coating, etc.) or deposition (chemical deposition, vapor deposition, hydrothermal deposition, electrochemical deposition, Joule thermal deposition, etc.).

[0052] Please see Figure 2This is a cross-sectional schematic diagram of a membrane electrode assembly provided in one embodiment of this application. The membrane electrode assembly 500 includes a cathode gas diffusion layer 201, a cathode catalyst layer 202, an anion exchange membrane 400, an anode catalyst layer 302, and an anode gas diffusion layer 301 stacked sequentially. At least one of the cathode catalyst layer 202 and the anode catalyst layer 302 is selected from the catalyst layers in any of the above embodiments. The catalyst layer provided in this application has better water adsorption and water retention performance, maintains the wettability of the catalyst layer, and is beneficial to reducing the interfacial impedance between the dry-side catalyst layer and the anion exchange membrane. At the same time, the membrane electrode assembly has good ion transport capability, which can improve the performance and service life of the membrane electrode assembly, especially suitable for use in electrolysis devices with single-sided liquid inlet.

[0053] In some embodiments of this application, the ion exchange capacity (IEC) of the anion exchange membrane is 1.5 mmol / g to 3.5 mmol / g. A high ion exchange capacity of the anion exchange membrane can improve ionic conductivity and ensure OH- - Water can quickly pass through the membrane, and the higher IEC of the anion exchange membrane results in a higher water absorption rate. This facilitates a closer interfacial contact between the anion exchange membrane and the anode and cathode catalyst layers. Especially in electrolysis devices with single-sided liquid inlet, water can be transported to the interface between the anion exchange membrane and the catalyst layer, allowing the catalyst layer to be fully wetted and better adsorb and retain water. This ensures that the interface remains moist during electrolysis, avoiding problems such as dryness and increased interfacial contact resistance. For example, the ion exchange capacity of the anion exchange membrane may be, but is not limited to, 1.5 mmol / g, 1.6 mmol / g, 1.7 mmol / g, 1.8 mmol / g, 1.9 mmol / g, 2 mmol / g, 2.1 mmol / g, 2.2 mmol / g, 2.3 mmol / g, 2.4 mmol / g, 2.5 mmol / g, 2.6 mmol / g, 2.7 mmol / g, 2.8 mmol / g, 2.9 mmol / g, 3 mmol / g, 3.1 mmol / g, 3.2 mmol / g, 3.3 mmol / g, 3.4 mmol / g, or 3.5 mmol / g.

[0054] In some embodiments of this application, the anode includes an anode gas diffusion layer and an anode catalyst layer, and the cathode includes a cathode gas diffusion layer and a cathode catalyst layer, wherein at least one of the anode and cathode is selected from the electrodes in any of the above embodiments. The anode gas diffusion layer and the cathode gas diffusion layer can be selected from the gas diffusion layer in the catalyst layer in any of the above embodiments. In some embodiments of this application, the prepared anode and cathode are bonded to anion exchange resin to obtain a membrane electrode assembly.

[0055] In some embodiments of this application, the thickness of the anion exchange membrane is 20 μm-300 μm, which is beneficial for electrolysis. Exemplary examples include, but are not limited to, thicknesses of 20 μm, 30 μm, 50 μm, 75 μm, 90 μm, 100 μm, 125 μm, 150 μm, 180 μm, 200 μm, 230 μm, 250 μm, 260 μm, 270 μm, or 300 μm.

[0056] In some embodiments of this application, the anion exchange membrane includes anion exchange resin, which may be selected from at least one of functionally modified polysulfone, polyphenylene ether, polyarylpiperidine, polyarylquinine, polynorbornene, polystyrene, polybenzimidazole, styrene-butadiene block copolymer, and polyethylene. The functional groups may be selected from at least one of quaternary ammonium cations, piperidinium cations, imidazolium cations, pyrrolidineium cations, quaternary phosphonium cations, guanidineium cations, quinine ring cations, and triazineium cations. This facilitates interaction with the binder in the catalyst layer, thereby enhancing the anion exchange membrane's ability to transport water to the catalyst layer.

[0057] In some embodiments of this application, the cathode catalyst layer is coated on the cathode gas diffusion layer or the anion exchange membrane. In some embodiments of this application, the anode catalyst layer is coated on the anode gas diffusion layer or the anion exchange membrane. The coating can be, but is not limited to, application by coating (spraying, roller coating, etc.) or deposition (chemical deposition, vapor deposition, hydrothermal deposition, electrochemical deposition, Joule thermal deposition, etc.). For example, a membrane electrode assembly can be fabricated by coating a cation catalyst layer onto the surface of the anion exchange membrane and then bonding the cation gas diffusion layer and the cathode; or a membrane electrode assembly can be fabricated by coating an anion catalyst layer onto the surface of the anion exchange membrane and then bonding the anion gas diffusion layer and the anode.

[0058] Please see Figure 3This is a schematic diagram of an electrolysis device provided in one embodiment of this application. The electrolysis device 600 includes a membrane electrode assembly 500, which includes a cathode gas diffusion layer 201, a cathode catalyst layer 202, an anion exchange membrane 400, an anode catalyst layer 302, and an anode gas diffusion layer 301 stacked sequentially. At least one of the cathode catalyst layer 202 and the anode catalyst layer 302 is selected from the catalyst layers in any of the above embodiments. The membrane electrode assembly provided in this application has excellent internal interface performance, which is beneficial to the electrolysis process of the electrolysis device. The electrolysis device provided in this application can perform electrolyte circulation by introducing electrolyte from both sides (both the anode side and the cathode side), or by introducing electrolyte from one side (either the anode side or the cathode side). The membrane electrode assembly can ensure the degree of water wetting on the non-injected side (i.e., the dry side) when introducing electrolyte from one side, reducing the internal interface resistance and improving the stability and reliability of the electrolysis device.

[0059] In some embodiments of this application, during electrolysis, the electrolyte is introduced into the side of the cathode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the electrolyte is not introduced into the side of the anode catalyst layer facing away from the anion exchange membrane. That is, by introducing electrolyte into the side of the cathode facing away from the anion exchange membrane, but not into the side of the anode facing away from the anion exchange membrane, single-sided electrolyte introduction at the cathode is achieved. The electrolysis device provided in this application can maintain the wetting effect on the dry side in a single-sided electrolyte introduction electrolysis process, which is beneficial for the use of the electrolysis device in electrolysis processes. In other embodiments of this application, during electrolysis, the electrolyte is introduced into the side of the anode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the electrolyte is not introduced into the side of the cathode catalyst layer facing away from the anion exchange membrane. In other words, by introducing electrolyte into the side of the anode away from the anion exchange membrane, but not introducing electrolyte into the side of the cathode away from the anion exchange membrane, single-sided liquid inlet of the anode is achieved. The electrolysis device provided in this application can maintain the wetting effect of the dry side in the single-sided liquid inlet electrolysis process, which is beneficial for the use of the electrolysis device in the electrolysis process.

[0060] In some embodiments of this application, such as Figure 3 As shown, the electrolysis apparatus 600 also includes a cathode chamber 200 and an anode chamber 300. The cathode chamber and the anode chamber are separated by an anion exchange membrane, with the cathode located in the cathode chamber and the anode located in the anode chamber; electrolyte can be introduced into both the cathode chamber and the anode chamber. Inlet and / or outlet ports may be provided in the cathode chamber and the anode chamber as needed.

[0061] The electrolysis apparatus provided in this application can be used to produce hydrogen, oxygen, etc. For example, the electrolysis apparatus can generate gas at a pressure of 0.1 MPa or higher. The electrolysis apparatus can be, but is not limited to, an anion exchange membrane (AEM) electrolyzer.

[0062] This application provides an electrolysis process in which an electrolyte is introduced into the electrolysis device of any of the above embodiments, and a voltage is applied to the cathode catalyst layer and the anode catalyst layer in the electrolysis device to perform electrolysis. The voltage can be provided by renewable energy or mains power, and the electrolysis can operate in a steady state or with dynamic fluctuations.

[0063] The electrolyte can be selected as needed. In some embodiments of this application, the electrolyte can be water. In another embodiment of this application, the electrolyte can be an aqueous solution containing an electrolyte. Exemplarily, the electrolyte can be, but is not limited to, at least one of KOH, NaOH, LiOH, K2CO3, KHCO3, Na2CO3, and NaHCO3. In some embodiments, the concentration of the electrolyte in the electrolyte is less than or equal to 7 mol / L, which is beneficial for the electrolysis of water. For example, the concentration of the electrolyte in the electrolyte solution can be, but is not limited to, 0.1 mol / L, 0.2 mol / L, 0.5 mol / L, 0.7 mol / L, 1 mol / L, 1.3 mol / L, 1.5 mol / L, 1.8 mol / L, 2 mol / L, 2.5 mol / L, 2.7 mol / L, 3 mol / L, 3.5 mol / L, 3.8 mol / L, 4 mol / L, 4.5 mol / L, 5 mol / L, 5.5 mol / L, 6 mol / L, 6.5 mol / L, or 7 mol / L. For instance, the concentration of the electrolyte in the electrolyte solution can be between 0.1 mol / L and 2 mol / L. During electrolysis, the anolyte reaction is 4OH⁻. - →O2 + 2H2O + 4e - The cathode reaction process is 4H₂O + 4e⁻ - →2H₂ + 4OH⁻ - .

[0064] In some embodiments of this application, the electrolyte is introduced from one side of the cathode or anode. Single-sided electrolyte introduction eliminates the need for a circulation and gas-liquid separation device, resulting in a more compact system structure and cost savings. Furthermore, the electrolysis device provided in this application exhibits excellent internal interface performance of the membrane electrode assembly, ensuring the dry side remains wetted during electrolysis without issues such as drying or cracking, thus improving electrolysis efficiency and reducing electrolysis costs. In some embodiments, when the electrolysis device introduces electrolyte from one side, with the electrolyte introduced from the cathode side, the anode catalyst layer is selected from any of the catalyst layers described in the above embodiments. In this case, the electrolysis device may further include a cathode inlet and a cathode outlet communicating with the cathode chamber, and an anode outlet communicating with the anode. The cathode inlet is used for passing electrolyte, the cathode outlet is used for discharging electrolyte and hydrogen, and the anode outlet is used for discharging oxygen. In other embodiments, when the electrolysis device is fed into the anode side only, the cathode catalyst layer is selected from the catalyst layer in any of the above embodiments; at this time, the electrolysis device may also include an anode inlet and an anode outlet communicating with the anode chamber, and a cathode outlet communicating with the cathode. The anode inlet is used to pass electrolyte, the anode outlet is used to discharge electrolyte and oxygen, and the cathode outlet is used to discharge hydrogen.

[0065] Please see Figure 4 This is a schematic diagram of the operation of an electrolysis device provided in one embodiment of this application. It shows a single-sided electrolyte inlet circulation at the anode. Arrow a1 indicates the direction of electrolyte inlet, arrow a2 indicates the direction of water movement in the membrane electrode assembly 500, and arrow a3 indicates the direction of OH- in the electrolysis device. - The direction of movement is indicated by arrow a4, which is the discharge direction of the outlet in the anode chamber 300, used to discharge electrolyte and oxygen, and arrow a5, which is the discharge direction of the outlet in the cathode chamber 200, used to discharge hydrogen.

[0066] Please see Figure 5 This is a schematic diagram of the operation of an electrolysis device provided in another embodiment of this application. It shows a single-sided cathode inlet circulation. Arrow b1 indicates the direction of electrolyte inlet, arrow b2 indicates the direction of water movement in the membrane electrode assembly 500, and arrow b3 indicates the direction of OH- in the electrolysis device. - The direction of movement is indicated by arrow b4, which is the discharge direction of the outlet in the anode chamber 300, used to discharge oxygen, and arrow b5, which is the discharge direction of the outlet in the cathode chamber 200, used to discharge electrolyte and hydrogen.

[0067] In some embodiments of this application, the electrolysis temperature can be between 25°C and 85°C, which is beneficial for the electrolysis process. Exemplary examples include, but are not limited to, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, or 85°C. In some embodiments, the electrolysis temperature can be between 30°C and 80°C.

[0068] The effects of the technical solution in this application will be further illustrated below with specific examples.

[0069] Experimental Group A Example A1-1 The binder is a modified polyarylpiperidine with modified groups, namely piperidine cationic group and hydroxyl group. The molar ratio of hydroxyl group to piperidine cationic group in the binder is 2%. The binder has an IEC of 2.4 mmol / g and a number average molecular weight of 10,000.

[0070] The binder and cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) were mixed at a mass ratio of 3:7, and isopropanol solvent was added. The mixture was ultrasonically dispersed to form a uniform slurry. The mixture was then ultrasonically sprayed onto carbon paper and dried to obtain a catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 23°.

[0071] Example A1-2 The difference from Example A1-1 is that the binder is a modified polyarylpiperidine with modified groups, the modified groups being piperidine cationic groups and -CF3 groups, the molar ratio of -CF3 groups to piperidine cationic groups in the binder is 1.5%, the IEC of the binder is 2.4 mmol / g, the number average molecular weight is 10000, and the static water contact angle of the catalyst layer is 43°.

[0072] Examples A1-3 The difference from Example A1-1 is that the binder is a modified polyarylpiperidine with modified groups, the modified groups being piperidine cationic groups and carboxyl groups, the molar ratio of carboxyl groups to piperidine cationic groups in the binder is 0.5%, the IEC of the binder is 2.4 mmol / g, the number average molecular weight is 10000, and the static water contact angle of the catalyst layer is 27°.

[0073] Examples A1-4 The difference from Example A1-1 is that the binder is a modified polyaromatic quinine with modified groups, the modified groups being quinine cyclic cationic groups and amino groups, the molar ratio of amino groups to quinine cyclic cationic groups in the binder is 5%, the IEC of the binder is 2.8 mmol / g, the number average molecular weight is 50,000, and the static water contact angle of the catalyst layer is 30°.

[0074] Examples A1-5 The difference from Example A1-1 is that the binder is polystyrene modified with modified groups, the modified groups being imidazole cationic groups and hydroxyl groups, the molar ratio of hydroxyl groups to imidazole groups in the binder is 0.5%, the IEC of the binder is 2 mmol / g, and the number average molecular weight is 20000; the static water contact angle of the catalyst layer is 41°.

[0075] Examples A1-6 The difference from Example A1-1 is that the binder is a modified polyarylpiperidine with modified groups, the modified groups being piperidine cationic groups and sulfonic acid groups, the molar ratio of sulfonic acid groups and piperidine cationic groups in the binder is 5%, the IEC of the binder is 2.0 mmol / g, the number average molecular weight is 100,000, and the static water contact angle of the catalyst layer is 67°.

[0076] Examples A1-7 The difference from Example A1-1 is that the modified groups are piperidine cationic groups, hydroxyl groups and sulfonic acid groups, the molar ratio of hydroxyl groups to piperidine cationic groups in the binder is 1%, the molar ratio of sulfonic acid groups to piperidine cationic groups is 1%, the IEC of the binder is 2.0 mmol / g, the number average molecular weight is 10000, and the static water contact angle of the catalyst layer is 25°.

[0077] Examples A1-8 The difference from Example A1-1 is that the molar ratio of hydroxyl groups to piperidine cationic groups in the binder is 12%, the IEC of the binder is 2.4 mmol / g, the number average molecular weight is 10000, and the static water contact angle of the catalyst layer is 20°.

[0078] Examples A1-9 The binder is a modified polyarylpiperidine with modified groups, namely piperidine cationic group and hydroxy group. The molar ratio of hydroxy group to piperidine cationic group in the binder is 2%. The binder has an IEC of 1.4 mmol / g and a number average molecular weight of 10,000.

[0079] The binder and cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) were mixed at a mass ratio of 3:7, and isopropanol solvent was added. The mixture was ultrasonically dispersed to form a uniform slurry. The mixture was then ultrasonically sprayed onto carbon paper and dried to obtain a catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 46°.

[0080] Examples A1-10 The binder is a modified polyarylpiperidine with modified groups, namely piperidine cationic group and hydroxy group. The molar ratio of hydroxy group to piperidine cationic group in the binder is 2%. The binder has an IEC of 3.6 mmol / g and a number average molecular weight of 10,000.

[0081] The binder and cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) were mixed at a mass ratio of 3:7, and isopropanol solvent was added. The mixture was ultrasonically dispersed to form a uniform slurry. The mixture was then ultrasonically sprayed onto carbon paper and dried to obtain a catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 20°.

[0082] Example A2-1 NiFe-LDH and polytetrafluoroethylene (PTFE) were mixed at a mass ratio of 8:2, and isopropanol solvent was added. The mixture was then ultrasonically dispersed to form a uniform slurry. The slurry was ultrasonically sprayed onto a nickel felt (0.4 mm thick) and dried at 60 °C to obtain a catalyst layer, thus producing the anode. The NiFe-LDH loading in the anode was 10 mg / cm³. 2 .

[0083] The above-mentioned anode, quaternized polyarylpiperidine anion exchange membrane (Alkymer W-75, IEC 2.5 mmol / g) and the cathode prepared in Example A1-1 were stacked and assembled in an electrolytic cell, with liquid circulation only on the anode side, and the electrolyte was a 1M KOH solution.

[0084] Example A2-2 The difference from Example A2-1 is that the cathode prepared in Example A1-2 is used.

[0085] Example A2-3 The difference from Example A2-1 is that the cathode prepared in Example A1-3 is used.

[0086] Examples A2-4 The difference from Example A2-1 is that the cathode prepared in Example A1-4 is used.

[0087] Examples A2-5 The difference from Example A2-1 is that the cathode prepared in Example A1-5 is used.

[0088] Examples A2-6 The difference from Example A2-1 is that the cathode prepared in Example A1-6 is used.

[0089] Examples A2-7 The difference from Example A2-1 is that the cathode prepared in Example A1-7 is used.

[0090] Examples A2-8 The difference from Example A2-1 is that the cathode prepared in Example A1-8 is used.

[0091] Examples A2-9 The difference from Example A2-1 is that the cathode prepared in Example A1-9 is used.

[0092] Example A2-10 The difference from Example A2-1 is that the cathode prepared in Example A1-10 is used.

[0093] Experimental Group B Example B1-1 The binder is a modified polyarylpiperidine with modified groups, namely piperidine cationic group and hydroxy group. The molar ratio of hydroxy group to piperidine cationic group in the binder is 2%. The binder has an IEC of 2.4 mmol / g and a number average molecular weight of 5000.

[0094] The binder and the anode catalyst NiFe-LDH were mixed at a mass ratio of 2:8, and then isopropanol solvent was added. The mixture was ultrasonically dispersed to form a uniform slurry. The slurry was then ultrasonically sprayed onto a nickel felt (0.4 mm thick) and dried at 60°C to obtain the catalyst layer, thus producing the anode. The NiFe-LDH loading in the anode was 10 mg / cm³. 2 The static water contact angle of the catalyst layer is 25°.

[0095] Example B2-1 The cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) was mixed with PTFE at a mass ratio of 7:3. The slurry was then coated onto carbon paper using ultrasonic spraying and dried to obtain the catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 .

[0096] The above-mentioned cathode, quaternized polyarylpiperidine anion exchange membrane (Alkymer W-75, IEC 2.5 mmol / g) and the anode prepared in Example B1-1 were stacked and assembled in an electrolytic cell, with liquid circulation only on the cathode side, and the electrolyte was a 1M KOH solution.

[0097] Comparative Example 1 NiFe-LDH and PTFE were mixed at a mass ratio of 8:2, and isopropanol solvent was added. The mixture was then ultrasonically dispersed to form a uniform slurry. The slurry was then ultrasonically sprayed onto a nickel felt (0.4 mm thick) and dried at 60 °C to obtain a catalyst layer, thus producing the anode. The NiFe-LDH loading in the anode was 10 mg / cm³. 2 The static water contact angle of the catalyst layer is 168°.

[0098] The cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) was mixed with PTFE at a mass ratio of 7:3. The slurry was then coated onto carbon paper using ultrasonic spraying and dried to obtain the catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 179°.

[0099] The cathode, the quaternized polyarylpiperidine anion exchange membrane (Alkymer W-75, IEC 2.5 mmol / g) and the anode were stacked and assembled in an electrolytic cell with double-sided liquid inlet circulation. The electrolyte was a 1M KOH solution.

[0100] Comparative Example 2 NiFe-LDH and PTFE were mixed at a mass ratio of 8:2, and isopropanol solvent was added. The mixture was then ultrasonically dispersed to form a uniform slurry. The slurry was then ultrasonically sprayed onto a nickel felt (0.4 mm thick) and dried at 60 °C to obtain a catalyst layer, thus producing the anode. The NiFe-LDH loading in the anode was 10 mg / cm³. 2 The static water contact angle of the catalyst layer is 168°.

[0101] The cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) was mixed with PTFE at a mass ratio of 7:3. The slurry was then coated onto carbon paper using ultrasonic spraying and dried to obtain the catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 179°.

[0102] The cathode, the quaternized polyarylpiperidine anion exchange membrane (Alkymer W-75, IEC 2.5 mmol / g) and the anode were stacked and assembled in an electrolytic cell, with liquid circulation only on the anode side, and the electrolyte was a 1M KOH solution.

[0103] Comparative Example 3 NiFe-LDH and PTFE were mixed at a mass ratio of 8:2, and isopropanol solvent was added. The mixture was then ultrasonically dispersed to form a uniform slurry. The slurry was then ultrasonically sprayed onto a nickel felt (0.4 mm thick) and dried at 60 °C to obtain a catalyst layer, thus producing the anode. The NiFe-LDH loading in the anode was 10 mg / cm³. 2 The static water contact angle of the catalyst layer is 168°.

[0104] The cathode catalyst Pt / C (Pt / C containing 40% Pt by mass) was mixed with PTFE at a mass ratio of 7:3. The slurry was then coated onto carbon paper using ultrasonic spraying and dried to obtain the catalyst layer, thus producing the cathode. The Pt loading in the catalyst layer was 0.5 mg / cm³. 2 The static water contact angle of the catalyst layer is 179°.

[0105] The cathode, the quaternized polyarylpiperidine anion exchange membrane (Alkymer W-75, IEC 2.5 mmol / g) and the anode were stacked and assembled in an electrolytic cell, with liquid circulation only on the cathode side, and the electrolyte was a 1M KOH solution.

[0106] Performance testing The performance of the electrolysis devices prepared in Examples A2-1 to A2-10, Example B2-1, and Comparative Examples 1 to 3 was tested as follows, with the operating temperature of the electrolysis devices being 60°C.

[0107] Ohmic impedance: Using an electrochemical workstation, the working electrode (WE) line and the working sensing electrode (WS) line were connected to the cathode side plate, and the reference electrode (RE) line and the auxiliary electrode line were connected to the anode side plate. The constant voltage AC impedance of the test object was measured at open circuit potential, with a high frequency of 100,000 Hz, a low frequency of 1 Hz, and an amplitude of 10 mV. After fitting the test results, the ohmic impedance (HFR) value was calculated based on the electrode area (the smaller of the anode surface area and the cathode surface area; in this test, the anode and cathode surface areas were equal). The results are shown in Table 1.

[0108] Electrolysis performance of the water electrolysis unit: Using an electrochemical workstation, the working electrode (WE) line and the working sensing electrode (WS) line are connected to the cathode side plate, and the reference electrode (RE) line and the auxiliary electrode line are connected to the anode side plate. A constant current testing method is employed, at 0 A / cm². 2 -1A / cm 2 Under the given current, 10 current steps were set, and each step was tested for 5 minutes. A voltage value was recorded every second. The voltage after stabilization on each current step was recorded. The response potential difference and the stable voltage during the load increase process were also recorded. The results are shown in Table 1.

[0109] Table 1 Performance Test Results

[0110] Both Example A2-1 and Comparative Example 2 involve anode-side circulating liquid inlet. The cathode-side electrode in Comparative Example 2 uses a hydrophobic binder, resulting in a cathode surface contact angle as high as 179°, classifying it as a superhydrophobic surface with almost no wetting. This makes it impossible to guarantee wetting at the interface between the cathode catalyst layer and the anion exchange membrane, leading to interface instability and poor water electrolysis performance. In Example A2-1, a specific hydrophilic binder is used in the cathode catalyst layer, making its surface hydrophilic. Simultaneously, the binder in the cathode catalyst layer and the high IEC anion exchange membrane work together to transport water from the anode to the cathode side via diffusion. Furthermore, the binder in the cathode catalyst layer ensures water wetting within it, forming a continuous ion and water transport channel. This electrolysis device exhibits lower ohmic impedance, a lower operating voltage at 1 A / cm², a lower response potential difference, and significantly improved long-term operational stability with a reduced voltage decay rate.

[0111] Both Example B2-1 and Comparative Example 3 involve cathode-side circulating liquid inlet. In Comparative Example 3, the anode catalyst layer uses a hydrophobic binder, resulting in a surface contact angle as high as 168°, classifying it as a superhydrophobic surface with almost no wetting. This makes it impossible to guarantee interfacial wetting between the anode catalyst layer and the anion exchange membrane, leading to interface instability and poor water electrolysis performance. In Example B2-1, a specific hydrophilic binder is used in the anode catalyst layer, making its surface hydrophilic. Simultaneously, the binder in the anode catalyst layer and the high IEC anion exchange membrane work together to transport water from the cathode to the anode side via electrodialysis and diffusion. Furthermore, the binder in the anode catalyst layer ensures water wetting within it, forming a continuous ion and water transport channel. This electrolysis device exhibits lower ohmic impedance, a lower operating voltage at 1 A / cm², a lower response potential difference, and significantly improved long-term operational stability with a reduced voltage decay rate.

[0112] As can be seen from Examples A2-1 to A2-10, Example B2-1, and Comparative Example 1, the HFR values, response potential differences, operating voltages, and decay rates of the examples are comparable to those of Comparative Example 1. This indicates that the electrode containing the binder in this application can effectively solve the problem of dryness at the existing single-sided liquid inlet interface, resulting in lower resistance to interfacial charge transfer and mass transport. At the same time, it can also work in conjunction with the high IEC anion exchange membrane to further improve the performance of the electrolysis device. Furthermore, compared to Comparative Example 1 with double-sided liquid inlet, the electrolysis device provided by the examples of this application not only eliminates the need for a circulation system but also has excellent electrochemical performance and long-term stability, making it more suitable for use.

[0113] The above description is an exemplary embodiment of this application, but it should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications are also considered to be within the scope of protection of this application.

Claims

1. A catalyst layer characterized by, The catalyst layer is made of a catalyst and a binder. The binder includes a main chain structure and modifying groups directly attached to the main chain structure. The modifying groups include cationic hydrophilic groups and non-cationic groups. The non-cationic groups are selected from at least one of sulfonic acid groups, phosphate groups, phosphonic acid groups, hydroxyl groups, carboxyl groups, amino groups, cyano groups, halogen groups, alkyl groups, haloalkyl groups, alkoxy groups, and heteroaryl groups.

2. The catalyst layer according to claim 1, wherein In the adhesive, the molar ratio of the non-cationic group to the cationic hydrophilic group is 0.1%-10%; and / or, The hydrophilic group of the cation includes at least one selected from quaternary ammonium cation, piperidinium cation, imidazolium cation, pyrrolidineium cation, quaternary phosphonium cation, guanidineium cation, quinine ring cation, and triazineium cation.

3. The catalyst layer according to any one of claims 1 to 2, wherein The main chain structure is selected from at least one of polysulfone, polyphenylene ether, polyarylpiperidine, polyarylquinine, polynorbornene, polystyrene, polybenzimidazole, styrene-butadiene block copolymer, and polyethylene; and / or, The number average molecular weight of the adhesive is 10 million to 1 million.

4. The catalyst layer according to any one of claims 1 to 3, wherein The static water contact angle of the catalyst layer is less than or equal to 90°; and / or, The mass content of the binder in the catalyst layer is 2%-50%; and / or, The ion exchange capacity of the binder is 1.5 mmol / g-3.5 mmol / g; and / or, The thickness of the catalyst layer is 3μm-40μm.

5. The catalyst layer according to any one of claims 1 to 4, wherein The catalyst is made of at least one metallic element selected from Ni, Fe, Co, Mn, Cu, Zn, Al, V, Cr, Mo, Ru, Au, Ag, Ir, Rh, Pd, Pt, and Re.

6. An electrode, characterized in that, It includes the catalyst layer and gas diffusion layer as described in any one of claims 1-5.

7. A membrane electrode assembly, characterized by It includes a cathode gas diffusion layer, a cathode catalyst layer, an anion exchange membrane, an anode catalyst layer, and an anode gas diffusion layer stacked sequentially, wherein at least one of the cathode catalyst layer and the anode catalyst layer is selected from the catalyst layer described in any one of claims 1-5.

8. The membrane electrode assembly of claim 7, wherein, The anion exchange membrane has an ion exchange capacity of 1.5 mmol / g to 3.5 mmol / g; and / or, The thickness of the anion exchange membrane is 20μm-300μm.

9. The membrane-electrode assembly as claimed in claim 7, characterized in that The cathode catalyst layer is coated on the cathode gas diffusion layer or the anion exchange membrane; and / or The anode catalyst layer is coated on the anode gas diffusion layer or the anion exchange membrane.

10. An electrolysis device, characterized by Includes the membrane electrode assembly as described in any one of claims 7-9.

11. The electrolytic device of claim 10, wherein During electrolysis, the electrolyte is introduced into the side of the cathode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the electrolyte is not introduced into the side of the anode catalyst layer facing away from the anion exchange membrane. or During electrolysis, the electrolyte is introduced into the side of the anode catalyst layer facing away from the anion exchange membrane in the membrane electrode assembly, while the electrolyte is not introduced into the side of the cathode catalyst layer facing away from the anion exchange membrane.

12. An electrolysis process characterized in that, Electrolyte is introduced into the electrolysis apparatus according to any one of claims 10-11, and voltage is applied to the cathode catalyst layer and the anode catalyst layer in the electrolysis apparatus to perform electrolysis.

13. The electrolysis process of claim 12, wherein, The electrolyte is introduced into the cathode catalyst layer, and the anode catalyst layer is selected from the catalyst layers described in any one of claims 1-5; or, The electrolyte is introduced into one side of the anode catalyst layer, and the cathode catalyst layer is selected from the catalyst layers described in any one of claims 1-5.

14. The electrolysis process as described in claim 12, characterized in that, The electrolyte is an aqueous solution containing an electrolyte, wherein the electrolyte includes at least one selected from KOH, NaOH, LiOH, K₂CO₃, KHCO₃, Na₂CO₃, and NaHCO₃, and the concentration of the electrolyte in the electrolyte is 0-7 mol / L; and / or The electrolysis temperature is 25℃-85℃.

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