Membrane electrode for producing hydrogen by electrolyzing water, preparation method of membrane electrode and electrolytic bath

Abstract

The invention provides a water electrolysis hydrogen production membrane electrode, a preparation method thereof and an electrolytic bath, and belongs to the technical field of water electrolysis hydrogen production, the water electrolysis hydrogen production membrane electrode comprises a composite anode layer, an anion exchange membrane and a composite cathode layer, and the composite anode layer comprises an anode substrate layer, a first gas diffusion layer and an anode catalyst layer. The anion exchange membrane is arranged on the side, provided with the anode catalyst layer, of the composite anode layer, the composite cathode layer is arranged on the side, away from the composite anode layer, of the anion exchange membrane, and the composite cathode layer comprises a cathode substrate layer, a second gas diffusion layer and a cathode catalyst layer. According to the water electrolysis hydrogen production membrane electrode provided by the embodiment of the invention, interface resistance among at least part of components can be eliminated, so that ion transmission and gas diffusion are smoother, and the electrolysis efficiency is improved.

Description

Technical Field

[0001] The present application relates to the technical field of hydrogen production by electrolyzing water, and particularly relates to a membrane electrode for hydrogen production by electrolyzing water, a preparation method thereof, and an electrolytic cell. Background Art

[0002] With the continuous growth of energy demand and the pursuit of clean energy, the technology of hydrogen production by electrolyzing water has attracted increasing attention. As an emerging electrolytic water technology, anion exchange membrane water electrolysis (AWMWE) has many advantages, such as the use of non-precious metal catalysts and relatively mild operating conditions. However, in related technologies, the membrane electrode in the anion exchange membrane water electrolysis system is usually assembled from multiple separated components, and the interfacial contact resistance between each component is relatively large, which easily leads to a reduction in electrolysis efficiency and increases the manufacturing cost and assembly difficulty. Summary of the Invention

[0003] Embodiments of the present application provide a membrane electrode for hydrogen production by electrolyzing water, a preparation method thereof, and an electrolytic cell, which can reduce the contact resistance between components, improve the electrolysis efficiency, and at the same time reduce the cost and assembly difficulty.

[0004] In a first aspect, embodiments of the present application provide a membrane electrode for hydrogen production by electrolyzing water, including:

[0005] A composite anode layer, which includes an anode base layer, a first gas diffusion layer, and an anode catalyst layer. The first gas diffusion layer is disposed on one side of the anode base layer, and the anode catalyst layer is disposed on the side of the first gas diffusion layer away from the anode base layer;

[0006] An anion exchange membrane, which is disposed on the side of the composite anode layer with the anode catalyst layer;

[0007] A composite cathode layer, which is disposed on the side of the anion exchange membrane away from the composite anode layer. The composite cathode layer includes a cathode base layer, a second gas diffusion layer, and a cathode catalyst layer. The second gas diffusion layer is disposed on one side of the cathode base layer, and the cathode catalyst layer is disposed on the side of the second gas diffusion layer away from the anode base layer, and the cathode catalyst layer is disposed close to the anion exchange membrane.

[0008] In some embodiments, the thickness of the anion exchange membrane is 20 μm - 150 μm.

[0009] In some embodiments, the material of the anode base layer includes at least one of nickel foam and nickel felt.

[0010] In some embodiments, the first gas diffusion layer includes a first interface layer, a first transition layer, and a first functional layer. The anode base layer, the first interface layer, the first transition layer, the first functional layer, and the anode catalyst layer are sequentially stacked along the thickness direction of the anode base layer;

[0011] The porosity of the first interface layer is P 1 , the porosity of the first transition layer is P 2 , the porosity of the first functional layer is P 3 , and they satisfy: P 1 > P 2 > P 3 .

[0012] In some embodiments, the porosity P 1 of the first interface layer is 70%-80%;

[0013] and / or, the porosity P 2 of the first transition layer is 50%-60%;

[0014] and / or, the porosity P 3 of the first functional layer is 30%-40%.

[0015] In some embodiments, the thickness of the first interface layer is 100μm - 300μm;

[0016] and / or, the thickness of the first transition layer is 50μm - 150μm;

[0017] and / or, the thickness of the first functional layer is 20μm - 50μm.

[0018] In some embodiments, the material of the cathode base layer includes at least one of carbon fiber material, porous ceramic material, and carbon nanotube-reinforced carbon fiber composite material.

[0019] In some embodiments, the second gas diffusion layer includes a second interface layer, a second transition layer, and a second functional layer, and the cathode base layer, the second interface layer, the second transition layer, the second functional layer, and the cathode catalyst layer are sequentially stacked along the thickness direction of the cathode base layer;

[0020] The porosity of the second interface layer is P 4 , the porosity of the second transition layer is P 5 , the porosity of the second functional layer is P 6 , and they satisfy: P 4 > P 5 > P 6 .

[0021] In some embodiments, the porosity P 4 of the second interface layer is 70%-80%;

[0022] and / or, the porosity P 5 of the second transition layer is 50%-60%;

[0023] and / or, the porosity P 6 of the second functional layer is 30%-40%.

[0024] In some embodiments, the thickness of the second interface layer is 100 μm - 300 μm;

[0025] and / or, the thickness of the second transition layer is 50 μm - 150 μm;

[0026] and / or, the thickness of the second functional layer is 20 μm - 50 μm.

[0027] In some embodiments, the anode catalyst layer includes a first anode catalyst sub-layer, a second anode catalyst sub-layer, and a third anode catalyst sub-layer;

[0028] The first gas diffusion layer, the first anode catalyst sub-layer, the second anode catalyst sub-layer, the third anode catalyst sub-layer, and the anion exchange membrane are sequentially stacked along the thickness direction of the anode base layer;

[0029] The mass ratio of the anode catalyst in the first anode catalyst sub-layer is A 1 , the mass ratio of the anode catalyst in the second anode catalyst sub-layer is A 2 , the mass ratio of the anode catalyst in the third anode catalyst sub-layer is A 3 , A 1 < A 2 < A 3 ; the mass ratio of the binder in the first anode catalyst sub-layer is B 1 , the mass ratio of the binder in the second anode catalyst sub-layer is B 2 , the mass ratio of the binder in the third anode catalyst sub-layer is B 3 , B 1 > B 2 > B 3 .

[0030] In some embodiments, in the first anode catalyst sub-layer, the mass ratio of the anode catalyst is 30% - 40%, and the mass ratio of the binder is 60% - 70%;

[0031] and / or, in the second anode catalyst sub-layer, the mass ratio of the anode catalyst is 40% - 60%, the mass ratio of the binder is 30% - 55%, and the mass ratio of the first ionomer is 5% - 10%;

[0032] and / or, in the third anode catalyst sub-layer, the mass ratio of the anode catalyst is 80% - 90%, and the mass ratio of the first ionomer is 10% - 20%.

[0033] In some embodiments, the cathode catalyst layer includes a first cathode catalyst sub-layer, a second cathode catalyst sub-layer, and a third cathode catalyst sub-layer;

[0034] The second gas diffusion layer, the first cathode catalyst sub-layer, the second cathode catalyst sub-layer, the third cathode catalyst sub-layer and the anion exchange membrane are sequentially stacked along the thickness direction of the cathode base layer;

[0035] The mass ratio of the cathode catalyst in the first cathode catalyst sub-layer is A 4 , the mass ratio of the cathode catalyst in the second cathode catalyst sub-layer is A 5 , the mass ratio of the cathode catalyst in the third cathode catalyst sub-layer is A 6 , A 4 <A 5 <A 6 ;

[0036] The mass ratio of the second binder in the first cathode catalyst sub-layer is B 4 , the mass ratio of the second binder in the second cathode catalyst sub-layer is B 5 , the mass ratio of the second binder in the third cathode catalyst sub-layer is B 6 , B 4 >B 5 >B 6 .

[0037] In some embodiments, in the first cathode catalyst sub-layer, the mass ratio of the cathode catalyst is 30%-40%, and the mass ratio of the second binder is 60%-70%;

[0038] And / or, in the second cathode catalyst sub-layer, the mass ratio of the cathode catalyst is 40%-60%, the mass ratio of the second binder is 30%-55%, and the mass ratio of the second ionomer is 5%-10%;

[0039] And / or, in the third cathode catalyst sub-layer, the mass ratio of the cathode catalyst is 80%-90%, and the mass ratio of the second ionomer is 10%-20%.

[0040] In some embodiments, the electrolytic water hydrogen production membrane electrode further includes an anode protection layer, the anode protection layer is disposed between the composite anode layer and the anion exchange membrane, and the anode protection layer is attached to the surface of the anion exchange membrane;

[0041] And / or, the electrolytic water hydrogen production membrane electrode further includes a cathode protection layer, the cathode protection layer is disposed between the composite cathode layer and the anion exchange membrane, and the cathode protection layer is attached to the surface of the anion exchange membrane.

[0042] In some embodiments, the thickness of the anode protection layer is 0.01 mm - 0.1 mm;

[0043] And / or, the thickness of the cathode protection layer is 0.01 mm - 0.1 mm.

[0044] In some embodiments, the material of the anode protective layer includes at least one of fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyethylene terephthalate, polyimide, and polyphenylene sulfide;

[0045] and / or, the material of the cathode protective layer includes at least one of fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyethylene terephthalate, polyimide, and polyphenylene sulfide.

[0046] In a second aspect, embodiments of the present application provide a method for preparing an electrolyzed water hydrogen production membrane electrode, including:

[0047] Coating a first gas diffusion layer slurry on one side of the anode base layer to form a first gas diffusion layer;

[0048] Coating an anode catalyst slurry on the side of the first gas diffusion layer facing away from the anode base layer to form an anode catalyst layer, obtaining a composite anode layer;

[0049] Coating a second gas diffusion layer slurry on one side of the cathode base layer to form a second gas diffusion layer;

[0050] Coating a cathode catalyst slurry on the side of the second gas diffusion layer facing away from the cathode base layer to form a cathode catalyst layer, obtaining a composite cathode layer;

[0051] Stacking the composite anode layer, the anion exchange membrane, and the composite cathode layer in sequence to obtain an electrolyzed water hydrogen production membrane electrode;

[0052] wherein, the anion exchange membrane is disposed on the side of the composite anode layer having the anode catalyst layer, the composite cathode layer is disposed on the side of the anion exchange membrane facing away from the composite anode layer, and the cathode catalyst layer is disposed close to the anion exchange membrane.

[0053] In some embodiments, coating the first gas diffusion layer slurry on one side of the anode base layer includes:

[0054] Spraying the first gas diffusion layer slurry on one side of the anode base layer, setting the spraying pressure to 0.3 MPa - 0.5 MPa, and setting the slurry flow rate to 50 mL / min - 100 mL / min;

[0055] Then, hot pressing and forming for 10 min - 30 min under the conditions of a temperature of 100 °C - 200 °C and a pressure of 5 MPa - 15 MPa.

[0056] In some embodiments, after obtaining the composite anode layer, it further includes:

[0057] Performing an activation treatment on the composite anode layer.

[0058] In a third aspect, an embodiment of the present application further provides an electrolytic cell, including the electrolytic water hydrogen production membrane electrode as described above, and / or a membrane electrode prepared by the preparation method of the electrolytic water hydrogen production membrane electrode as described above.

[0059] Advantageous effects of the embodiment of the present application:

[0060] In the embodiment of the present application, the electrolytic water hydrogen production membrane electrode includes a composite anode layer, an anion exchange membrane, and a composite cathode layer. Among them, the composite anode layer includes an anode base layer, a first gas diffusion layer, and an anode catalyst layer. The first gas diffusion layer is disposed on one side of the anode base layer, and the anode catalyst layer is disposed on the side of the first gas diffusion layer away from the anode base layer. The anion exchange membrane is disposed on the side of the composite anode layer with the anode catalyst layer, and the composite cathode layer is disposed on the side of the anion exchange membrane away from the composite anode layer. The composite cathode layer includes a cathode base layer, a second gas diffusion layer, and a cathode catalyst layer. The second gas diffusion layer is disposed on one side of the cathode base layer, and the cathode catalyst layer is disposed on the side of the second gas diffusion layer away from the anode base layer, and the cathode catalyst layer is disposed close to the anion exchange membrane. By integrating the anode base layer, the first gas diffusion layer, and the anode catalyst layer in the composite anode layer, and the composite cathode layer inheriting the cathode base layer, the second gas diffusion layer, and the cathode catalyst layer, the number of components in the membrane electrode can be reduced, the interfacial resistance between at least some components can be eliminated, the ion transport and gas diffusion can be made smoother, and the electrolysis efficiency can be improved. Since the layers in the composite anode layer and the composite cathode layer can form a tight bond, the electrolytic water hydrogen production membrane electrode is not prone to problems such as delamination and interfacial corrosion during operation, improving the stability during long-term operation. At the same time, since the number of components in the electrolytic water hydrogen production membrane electrode is reduced, the assembly process can be simplified, the waste caused by the machining allowance in the multi-layer composite process in the traditional technology can be reduced, and the production cost can be lowered. Description of the Drawings

[0061] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0062] Figure 1 is a schematic cross-sectional structure of the electrolytic water hydrogen production membrane electrode provided by the embodiment of the present application Figure 1 ;

[0063] Figure 2 is a schematic cross-sectional structure of the electrolytic water hydrogen production membrane electrode provided by the embodiment of the present application Figure 2 ;

[0064] Figure 3Schematic cross-sectional structure of the electrolyzed water hydrogen production membrane electrode provided by the embodiment of the present application Figure 3 ;

[0065] Figure 4 Schematic cross-sectional structure of the electrolyzed water hydrogen production membrane electrode provided by the embodiment of the present application Figure 4 ;

[0066] Figure 5 is Figure 4 the enlarged view of part A in

[0067] Figure 6 Polarization performance test diagram of the embodiment and comparative example in the present application;

[0068] Figure 7 Long-term stability test diagram of the embodiment and comparative example in the present application.

[0069] Explanation of reference numerals:

[0070] 1. Composite anode layer; 11. Anode base layer; 12. First gas diffusion layer; 121. First interface layer; 122. First transition layer; 123. First functional layer; 13. Anode catalyst layer; 131. First anode catalyst sub-layer; 132. Second anode catalyst sub-layer; 133. Third anode catalyst sub-layer; 2. Anion exchange membrane; 3. Composite cathode layer; 31. Cathode base layer; 32. Second gas diffusion layer; 321. Second interface layer; 322. Second transition layer; 323. Second functional layer; 33. Cathode catalyst layer; 331. First cathode catalyst sub-layer; 332. Second cathode catalyst sub-layer; 333. Third cathode catalyst sub-layer; 4. Anode protection layer; 5. Cathode protection layer. Specific embodiments

[0071] The technical solutions in the embodiments of the present application will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0072] In the first aspect, as Figure 1As shown in the figure, an embodiment of the present application provides an electrolytic water hydrogen production membrane electrode, which includes a composite anode layer 1, an anion exchange membrane 2, and a composite cathode layer 3. Among them, the composite anode layer 1 includes an anode base layer 11, a first gas diffusion layer 12, and an anode catalyst layer 13. The first gas diffusion layer 12 is disposed on one side of the anode base layer 11, and the anode catalyst layer 13 is disposed on the side of the first gas diffusion layer 12 away from the anode base layer 11. The anion exchange membrane 2 is disposed on the side of the composite anode layer 1 having the anode catalyst layer 13. The composite cathode layer 3 is disposed on the side of the anion exchange membrane 2 away from the composite anode layer 1. The composite cathode layer 3 includes a cathode base layer 31, a second gas diffusion layer 32, and a cathode catalyst layer 33. The second gas diffusion layer 32 is disposed on one side of the cathode base layer 31, and the cathode catalyst layer 33 is disposed on the side of the second gas diffusion layer 32 away from the anode base layer 11, and the cathode catalyst layer 33 is disposed close to the anion exchange membrane 2. By integrating the anode base layer 11, the first gas diffusion layer 12, and the anode catalyst layer 13 in the composite anode layer 1, and the composite cathode layer 3 integrating the cathode base layer 31, the second gas diffusion layer 32, and the cathode catalyst layer 33, the number of components in the membrane electrode can be reduced, the interfacial resistance between at least some components can be eliminated, so that ion transport and gas diffusion are smoother, and the electrolysis efficiency is improved. Since the composite anode layer 1 and the composite cathode layer 3 can form a tight bond between the layers, the electrolytic water hydrogen production membrane electrode is not prone to problems such as delamination and interfacial corrosion during operation, and the stability during long-term operation is improved. At the same time, since the number of components in the electrolytic water hydrogen production membrane electrode is reduced, the assembly process can be simplified, the waste caused by the machining allowance in the multi-layer composite process in the traditional technology can be reduced, and the production cost can be reduced.

[0073] In some embodiments, the thickness of the anion exchange membrane 2 is 20μm - 150μm. The anion exchange membrane 2 can allow anions to pass through while blocking the passage of cations and other substances, thereby ensuring the efficiency and purity of the electrolysis process. By setting the thickness of the anion exchange membrane 2 to 20μm - 150μm, it can ensure that the electrolytic water hydrogen production membrane electrode can effectively perform ion exchange, and at the same time maintain sufficient mechanical strength and stability to meet the technical requirements of the electrolytic water hydrogen production membrane electrode.

[0074] Exemplarily, the thickness of the anion exchange membrane 2 can be 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, or 150μm.

[0075] In some embodiments, in the anode catalyst layer 13, the anode catalyst includes at least one of NiFe catalyst, NiMo catalyst, and NiCoFe catalyst. The NiFe catalyst, NiMo catalyst, and NiCoFe catalyst are all non-noble metal-based catalysts, which have low costs and high catalytic activities.

[0076] In some embodiments, in the cathode catalyst layer 33, the cathode catalyst includes at least one of platinum (Pt), ruthenium (Ru), iridium (Ir), nickel (Ni), cobalt (Co), and iron (Fe).

[0077] In some embodiments, the material of the anode substrate layer 11 includes at least one of nickel foam and nickel felt.

[0078] Among them, nickel foam is a three-dimensional reticulated foam metal material with high permeability and low density, and has a large number of micropores inside, enabling the electrolyte to more easily penetrate into the electrolysis interior, thereby improving the electrolysis efficiency. Moreover, nickel foam has a large specific surface area, good electrical conductivity and stability, can provide more active sites, and enables electrons to transfer smoothly in the reaction environment. Nickel felt also has high porosity and permeability, which is conducive to the penetration of the electrolyte and gas diffusion, thereby improving the electrolysis efficiency. In addition, nickel felt has high mechanical strength and wear resistance, can maintain a good shape and stability during the electrolysis process, and prolongs the service life.

[0079] In some embodiments, as Figure 2 shown, the first gas diffusion layer 12 includes a first interface layer 121, a first transition layer 122, and a first functional layer 123. The anode substrate layer 11, the first interface layer 121, the first transition layer 122, the first functional layer 123, and the anode catalyst layer 13 are sequentially stacked along the thickness direction of the anode substrate layer 11. The porosity of the first interface layer 121 is P 1 , the porosity of the first transition layer 122 is P 2 , the porosity of the first functional layer 123 is P 3 , and they satisfy: P 1 >P 2 >P 3 .

[0080] That is, the first gas diffusion layer 12 has a gradient porosity structure, with a larger porosity on the side closer to the anode base layer 11 and a smaller porosity on the side closer to the anode catalyst layer 13. The setting of the gradient porosity means that the porosity of the first gas diffusion layer 12 gradually changes from one side to the other, which helps to optimize the gas and liquid transport paths. On the side closer to the anode catalyst layer 13, the first functional layer 123 with a smaller porosity can provide a larger surface area for gas-catalyst contact, thus improving the reaction efficiency. On the side far from the anode catalyst, the first interface layer 121 with a larger porosity helps to reduce the resistance of gas transport, enabling the gas to enter or leave the gas diffusion layer more smoothly. In addition, the first gas diffusion layer 12 with a gradient porosity is more stable in structure, can reduce the problem of stress concentration, and improve the mechanical strength of the first gas diffusion layer 12.

[0081] In some embodiments, the porosity P of the first interface layer 121 1 is 70%-80%. The first interface layer 121 is arranged close to the anode base layer 11 and has a relatively high porosity, which helps to reduce the resistance of gas transport, enables the reaction gas to leave the gas diffusion layer more smoothly, thereby improving the electrolysis efficiency, and the first interface layer 121 with a relatively high porosity also helps to discharge the moisture generated during the reaction from the gas diffusion layer.

[0082] Exemplarily, the porosity P of the first interface layer 121 1 can be 70%, 72%, 75%, 78% or 80%.

[0083] In some embodiments, the porosity P of the first transition layer 122 2 is 50%-60%. The porosity P of the first transition layer 122 located between the first interface layer 121 and the first functional layer 123 2 is set to 50%-60%, which can ensure smooth gas transport while effectively balancing the pressure loss, can not only meet the requirements of efficient gas penetration, but also reduce the sharp drop in pressure caused by too large porosity. The porosity of the first transition layer 122 is set to 50%-60%, which also helps to reduce the phenomenon of local accumulation or shortage of gas during the transport process, and improve the gas utilization rate and electrolysis efficiency.

[0084] Exemplarily, the porosity P of the first transition layer 122 2 can be 50%, 52%, 55%, 58% or 60%.

[0085] In some embodiments, the porosity P of the first functional layer 123 3 is 30%-40%. By setting the porosity P of the first functional layer 123 close to the anode catalyst layer 13 3Set to 30%-40%, it helps to improve the full contact between the anode catalyst layer 13 and the reaction gas, thereby improving the activity of the catalyst in the anode catalyst layer 13 and enhancing the rate and efficiency of hydrogen production by electrolyzing water. The first functional layer 123 has a lower porosity, which can ensure its mechanical strength and reduce the structural damage caused by gas pressure or temperature changes during the electrolysis process.

[0086] Exemplarily, the porosity P of the first functional layer 123 3 can be 30%, 32%, 35%, 38% or 40%.

[0087] In some embodiments, the thickness of the first interface layer 121 is 100 μm - 300 μm. When the thickness of the first interface layer 121 is within the above range, it can provide sufficient gas transmission channels, provide good mechanical strength, and ensure stability.

[0088] In some embodiments, the thickness of the first transition layer 122 is 50 μm - 150 μm. By setting the thickness of the first transition layer 122 to 50 μm - 150 μm, it can ensure a good transition effect, optimize the gas and moisture transmission paths, and at the same time ensure the mechanical strength of the first transition layer 122.

[0089] In some embodiments, the thickness of the first functional layer 123 is 20 μm - 50 μm. By setting the thickness of the first functional layer 123 to 20 μm - 50 μm, it can make the anode catalyst layer 13 better adhere to the surface of the first functional layer 123, ensure the adhesion effect, and help to improve the full contact between the anode catalyst layer 13 and the reaction gas, thereby improving the activity of the catalyst in the anode catalyst layer 13 and enhancing the rate and efficiency of hydrogen production by electrolyzing water.

[0090] In some embodiments, the material of the cathode base layer 31 includes at least one of carbon fiber material, porous ceramic material, and carbon nanotube-reinforced carbon fiber composite material.

[0091] Among them, the carbon fiber material has excellent electrical conductivity, corrosion resistance, and relatively high strength, which can improve the electron transport performance and has good stability. The porous ceramic material has stable chemical and physical properties, excellent structural stability, and the porous ceramic material itself has catalytic performance, which can improve the reaction rate of hydrogen production by electrolyzing water. The carbon nanotube-reinforced carbon fiber composite material combines the advantages of carbon fiber and carbon nanotube, has relatively high strength and toughness, improves the electrical conductivity and catalytic performance, and can improve the efficiency of hydrogen production by electrolyzing water.

[0092] In some embodiments, such as Figure 2As shown, the second gas diffusion layer 32 includes a second interface layer 321, a second transition layer 322, and a second functional layer 323. The cathode base layer 31, the second interface layer 321, the second transition layer 322, the second functional layer 323, and the cathode catalyst layer 33 are sequentially stacked along the thickness direction of the cathode base layer 31. The porosity of the second interface layer 321 is P 4 , the porosity of the second transition layer 322 is P 5 , and the porosity of the second functional layer 323 is P 6 , satisfying: P 4 > P 5 > P 6 .

[0093] Similar to the composite anode layer 1, the second gas diffusion layer 32 in the composite cathode layer 3 also adopts a gradient porosity setting. The gradient porosity setting means that the porosity of the second gas diffusion layer 32 gradually changes from one side to the other, which helps to optimize the gas and liquid transport paths. On the side close to the cathode catalyst layer 33, the second functional layer 323 with a smaller porosity can provide a larger surface area for gas-catalyst contact, thereby improving the reaction efficiency. On the side far from the cathode catalyst, the second interface layer 321 with a larger porosity helps to reduce the resistance of gas transport, enabling the gas to enter or leave the second gas diffusion layer 32 more smoothly. In addition, the second gas diffusion layer 32 with gradient porosity is more stable in structure, can reduce the problem of stress concentration, and improve the mechanical strength of the second gas diffusion layer 32.

[0094] In some embodiments, the porosity P 4 of the second interface layer 321 is 70% - 80%. The advantages of setting the porosity P 4 of the second interface layer 321 to 70% - 80% are the same as those of the first interface layer 121 and will not be elaborated here.

[0095] In some embodiments, the porosity P 5 of the second transition layer 322 is 50% - 60%. The advantages of setting the porosity P 5 of the second transition layer 322 to 50% - 60% are the same as those of the first transition layer 122 and will not be elaborated here.

[0096] In some embodiments, the porosity P 6 of the second functional layer 323 is 30% - 40%. The advantages of setting the porosity P 6 of the second functional layer 323 to 50% - 60% are the same as those of the first functional layer 123 and will not be elaborated here.

[0097] In some embodiments, the thickness of the second interface layer 321 is 100 μm - 300 μm. The advantages of setting the thickness of the second interface layer 321 to 100 μm - 300 μm are the same as those of the first interface layer 121, which will not be elaborated here.

[0098] In some embodiments, the thickness of the second transition layer 322 is 50 μm - 150 μm. The advantages of setting the thickness of the second transition layer 322 to 50 μm - 150 μm are the same as those of the first transition layer 122, which will not be elaborated here.

[0099] In some embodiments, the thickness of the second functional layer 323 is 20 μm - 50 μm. The advantages of setting the thickness of the second functional layer 323 to 20 μm - 50 μm are the same as those of the first functional layer 123, which will not be elaborated here.

[0100] In some embodiments, as Figure 4 and Figure 5 shown, the anode catalyst layer 13 includes a first anode catalyst sub - layer 131, a second anode catalyst sub - layer 132, and a third anode catalyst sub - layer 133. The first gas diffusion layer 12, the first anode catalyst sub - layer 131, the second anode catalyst sub - layer 132, the third anode catalyst sub - layer 133, and the anion exchange membrane 2 are sequentially stacked along the thickness direction of the anode base layer 11. The mass ratio of the anode catalyst in the first anode catalyst sub - layer 131 is A 1 , the mass ratio of the anode catalyst in the second anode catalyst sub - layer 132 is A 2 , the mass ratio of the anode catalyst in the third anode catalyst sub - layer 133 is A 3 , A 1 <A 2 <A 3 , the mass ratio of the first binder in the first anode catalyst sub - layer 131 is B 1 , the mass ratio of the first binder in the second anode catalyst sub - layer 132 is B 2 , the mass ratio of the first binder in the third anode catalyst sub - layer 133 is B 3 , B 1 >B 2 >B 3 .

[0101] That is, the anode catalyst layer 13 includes a first anode catalyst sub-layer 131, a second anode catalyst sub-layer 132, and a third anode catalyst sub-layer, and there are differences in the ratios of the anode catalyst and the first binder in the first anode catalyst sub-layer 131, the second anode catalyst sub-layer 132, and the third anode catalyst sub-layer. In the first anode catalyst sub-layer 131 disposed adjacent to the first gas diffusion layer 12, the mass ratio of the anode catalyst is relatively low, and the ratio of the first binder is relatively high. The mass ratio of the anode catalyst in the second anode catalyst sub-layer 132 and the third anode catalyst sub-layer 133 gradually increases, and the mass ratio of the first binder gradually decreases. Through the above setting method, the bonding strength between the anode catalyst layer 13 and the first gas diffusion layer 12 can be ensured, and the reaction activity can be ensured.

[0102] In some embodiments, in the first anode catalyst sub-layer 131, the mass ratio of the anode catalyst is 30%-40%, and the mass ratio of the first binder is 60%-70%.

[0103] By setting the mass ratio of the first binder in the first anode catalyst sub-layer 131 to 60%-70%, the good bonding performance between the first anode catalyst sub-layer 131 and the first gas diffusion layer 12 can be ensured. By setting the mass ratio of the anode catalyst in the first anode catalyst sub-layer 131 to 30%-40%, a certain catalytic reaction activity can be ensured.

[0104] In some embodiments, in the second anode catalyst sub-layer 132, the mass ratio of the anode catalyst is 40%-60%, the mass ratio of the first binder is 30%-55%, and the mass ratio of the first ionomer is 5%-10%.

[0105] By setting the mass ratio of the first binder in the second anode catalyst sub-layer 132 to 30%-55%, a good transition effect can be ensured, and good bonding between the first anode catalyst sub-layer 131 and the third anode catalyst sub-layer 133 can be achieved. By setting the mass ratio of the anode catalyst in the second anode catalyst sub-layer 132 to 40%-60%, good catalytic reaction activity can be ensured. By adding a first ionomer with a mass ratio of 5%-10% to the second anode catalyst sub-layer 132, the proton transport effect can be promoted, the mechanical stability can be enhanced, and the reaction efficiency can be improved.

[0106] In some embodiments, in the third anode catalyst sub-layer 133, the mass ratio of the anode catalyst is 80%-90%, and the mass ratio of the first ionomer is 10%-20%.

[0107] By setting the mass ratio of the anode catalyst in the third anode catalyst sub-layer 133 to 80% - 90%, the catalytic activity can be improved. Since the third anode catalyst sub-layer 133 is in direct contact with the anion exchange membrane 2, a higher proportion of the anode catalyst can improve the catalytic reaction activity and ensure the reaction efficiency. By adding a first ionomer with a mass ratio of 10% - 20% to the third anode catalyst sub-layer 133, the proton transfer effect can be promoted, the mechanical stability can be enhanced, and the reaction efficiency can be improved.

[0108] In some embodiments, such as Figure 4 and Figure 5 shown, the cathode catalyst layer 33 includes a first cathode catalyst sub-layer 331, a second cathode catalyst sub-layer 332, and a third cathode catalyst sub-layer 333. The second gas diffusion layer 32, the first cathode catalyst sub-layer 331, the second cathode catalyst sub-layer 332, the third cathode catalyst sub-layer 333, and the anion exchange membrane 2 are sequentially stacked along the thickness direction of the cathode base layer 31. The mass ratio of the cathode catalyst in the first cathode catalyst sub-layer 331 is A 4 , the mass ratio of the cathode catalyst in the second cathode catalyst sub-layer 332 is A 5 , the mass ratio of the cathode catalyst in the third cathode catalyst sub-layer 333 is A 6 , A 4 <A 5 <A 6 , the mass ratio of the second binder in the first cathode catalyst sub-layer 331 is B 4 , the mass ratio of the second binder in the second cathode catalyst sub-layer 332 is B 5 , the mass ratio of the second binder in the third cathode catalyst sub-layer 333 is B 6 , B 4 >B 5 >B 6 .

[0109] Similar to the anode catalyst layer 13, the mass ratios of the cathode catalyst and the second binder in the cathode catalyst layer 33 also adopt a gradient setting form, and the achieved effects are similar to those of the anode catalyst layer 13, which will not be elaborated here.

[0110] In some embodiments, in the first cathode catalyst sub-layer 331, the mass ratio of the cathode catalyst is 30% - 40%, and the mass ratio of the second binder is 60% - 70%.

[0111] In some embodiments, in the second cathode catalyst sub-layer 332, the mass ratio of the cathode catalyst is 40% - 60%, the mass ratio of the second binder is 30% - 55%, and the mass ratio of the second ionomer is 5% - 10%;

[0112] In some embodiments, in the third cathode catalyst sub-layer 333, the mass ratio of the cathode catalyst is 80%-90%, and the mass ratio of the second ionomer is 10%-20%.

[0113] In the above embodiments, in the first cathode catalyst sub-layer 331, the second cathode catalyst sub-layer 332, and the third cathode catalyst sub-layer 333, the advantages generated by the proportions of the components are similar to those of the first anode catalyst sub-layer 131, the second anode catalyst sub-layer 132, and the third anode catalyst sub-layer 133, and will not be elaborated here.

[0114] In some embodiments, both the first binder and the second binder include at least one of polytetrafluoroethylene (PTFE) and polyvinylidene fluoride (PVDF).

[0115] In some embodiments, both the first ionomer and the second ionomer include at least one of ALkymer ionomer, Ionomr ionomer, and Versogen ionomer.

[0116] In some embodiments, as Figure 3 shown, the electrolytic water hydrogen production membrane electrode further includes an anode protection layer 4. The anode protection layer 4 is disposed between the composite anode layer 1 and the anion exchange membrane 2, and the anode protection layer 4 is adhesively disposed on the surface of the anion exchange membrane 2.

[0117] In some embodiments, as Figure 3 shown, the electrolytic water hydrogen production membrane electrode further includes a cathode protection layer 5. The cathode protection layer 5 is disposed between the composite cathode layer 3 and the anion exchange membrane 2, and the cathode protection layer 5 is adhesively disposed on the surface of the anion exchange membrane 2.

[0118] The anode protection layer 4 and the cathode protection layer 5 can respectively provide a protective effect on the anode catalyst layer 13 and the cathode catalyst layer 33. At the same time, they can also improve the sealing effect, reduce problems such as current leakage, and ensure the stability of the electrolysis system. The anode protection layer 4 and the cathode protection layer 5 are respectively adhesively disposed on both sides of the anion exchange membrane 2, which can provide a protective effect on the anion exchange membrane 2 and reduce the wear of the anion exchange membrane 2. At the same time, the anode protection layer 4 and the anode protection layer 4 can also form a good sealing effect, which can reduce problems such as electrolyte leakage and ensure the stable operation of the electrolysis system. In addition, the anode protection layer 4, the anion exchange membrane 2, and the cathode protection layer 5 can be integrated into a whole to achieve modular design, which is convenient for maintenance and replacement, and reduces the operation difficulty and cost.

[0119] In some embodiments, the thickness of the anode protective layer 4 is 0.01 mm - 0.1 mm. When the thickness of the anode protective layer 4 is within this range, it can effectively block unnecessary ions or molecules, reduce the generation of side reactions, and ensure that the selective ion conduction function of the anion exchange membrane 2 is not disturbed. The anode protective layer 4 can provide good physical protection and sealing effect for the anion exchange membrane 2.

[0120] In some embodiments, the thickness of the cathode protective layer 5 is 0.01 mm - 0.1 mm. Similarly, when the thickness of the cathode protective layer 5 is within this range, it can effectively block unnecessary ions or molecules, reduce the generation of side reactions, and ensure that the selective ion conduction function of the anion exchange membrane 2 is not disturbed. The cathode protective layer 5 can provide good physical protection and sealing effect for the anion exchange membrane 2.

[0121] In some embodiments, the material of the anode protective layer 4 includes at least one of fluorinated ethylene propylene copolymer (FEP), polytetrafluoroethylene (PTFE), polyethylene terephthalate (PET), polyimide (PI), and polyphenylene sulfide (PPS). FEP, PTFE, PET, PI, and PPS all have good mechanical stability and corrosion resistance and other properties. As the material of the anode protective layer 4, it can improve the durability and safety of the electrolytic water hydrogen production membrane electrode.

[0122] In some embodiments, the material of the cathode protective layer 5 includes at least one of fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyethylene terephthalate, polyimide, and polyphenylene sulfide. FEP, PTFE, PET, PI, and PPS all have good mechanical stability and corrosion resistance and other properties. As the material of the cathode protective layer 5, it can improve the durability and safety of the electrolytic water hydrogen production membrane electrode.

[0123] In a second aspect, embodiments of the present application provide a method for preparing an electrolytic water hydrogen production membrane electrode, including:

[0124] Coating a first gas diffusion layer 12 slurry on one side of the anode base layer 11 to form the first gas diffusion layer 12;

[0125] Coating an anode catalyst slurry on the side of the first gas diffusion layer 12 facing away from the anode base layer 11 to form an anode catalyst layer 13, obtaining a composite anode layer 1;

[0126] Coating a second gas diffusion layer 32 slurry on one side of the cathode base layer 31 to form the second gas diffusion layer 32;

[0127] Coating a cathode catalyst slurry on the side of the second gas diffusion layer 32 facing away from the cathode base layer 31 to form a cathode catalyst layer 33, obtaining a composite cathode layer 3;

[0128] The composite anode layer 1, the anion exchange membrane 2, and the composite cathode layer 3 are stacked in sequence to obtain an electrolytic water hydrogen production membrane electrode;

[0129] Among them, the anion exchange membrane 2 is disposed on the side of the composite anode layer 1 having the anode catalyst layer 13, the composite cathode layer 3 is disposed on the side of the anion exchange membrane 2 facing away from the composite anode layer 1, and the cathode catalyst layer 33 is disposed close to the anion exchange membrane 2.

[0130] That is, in the preparation method of the electrolytic water hydrogen production membrane electrode provided by the embodiments of the present application, by coating and forming the first gas diffusion layer 12 on the anode substrate layer 11, and then coating and forming the anode catalyst layer 13 on the first gas diffusion layer 12, the composite anode layer 1 including the anode substrate layer 11, the first gas diffusion layer 12, and the anode catalyst layer 13 is formed, which can make the structures of the layers in the composite anode layer 1 contact closely, reduce the interface resistance, and help reduce problems such as delamination and interface corrosion, realizing long-term stable operation.

[0131] Similarly, in the embodiments of the present application, the structures of the layers in the composite cathode layer 3 contact closely, reduce the interface resistance, and help reduce problems such as delamination and interface corrosion, realizing long-term stable operation.

[0132] The preparation method of the electrolytic water hydrogen production membrane electrode provided by the embodiments of the present application has all the beneficial effects of the electrolytic water hydrogen production membrane electrode as described above, and will not be elaborated here.

[0133] In some embodiments, coating the first gas diffusion layer 12 slurry on one side of the anode substrate layer 11 includes:

[0134] Spraying the first gas diffusion layer 12 slurry on one side of the anode substrate layer 11, setting the spraying pressure to 0.3 MPa - 0.5 MPa, and setting the slurry flow rate to 50 mL / min - 100 mL / min;

[0135] Then hot pressing and forming for 10 min - 30 min under the conditions of a temperature of 100°C - 200°C and a pressure of 5 MPa - 15 MPa.

[0136] By setting the spraying pressure at 0.3 MPa - 0.5 MPa, the splashing of the slurry during the spraying process can be reduced, and the slurry can fully penetrate into the voids of the anode substrate layer 11 to form a tight bond. A slurry flow rate of 50 mL / min - 100 mL / min can ensure the continuity and stability of the spraying process, which helps to form a uniform coating. After spraying, by hot pressing at a temperature of 100°C - 200°C and a pressure of 5 MPa - 15 MPa, it can ensure that the solvent in the slurry can volatilize, making the slurry form a tight structure, and enabling the formed first gas diffusion layer 12 to form a good bond with the anode substrate layer 11, improving the overall density and conductivity. By maintaining the hot pressing time for 10 min - 30 min, the stability can be improved.

[0137] In some embodiments, an anode catalyst slurry is coated on the side of the first gas diffusion layer 12 facing away from the anode substrate layer 11, including:

[0138] The anode substrate with the first gas diffusion layer 12 formed thereon is immersed in the anode catalyst slurry, so that the anode catalyst slurry is loaded on the surface and pores of the first gas diffusion layer 12 on the side facing away from the anode substrate layer 11. After drying and heat treatment, an anode catalyst layer 13 is formed.

[0139] Among them, the anode catalyst slurry can be formed by dispersing an anode catalyst precursor in an aqueous solution containing an appropriate amount of surfactant. The mass - volume ratio of the anode catalyst precursor in the anode catalyst slurry can be 0.05% - 0.5%.

[0140] In some embodiments, the anode catalyst layer 13 can be obtained by spraying or screen printing. Through spraying or screen printing, the hierarchical structure can be regulated, so as to obtain a first anode catalyst sub - layer 131, a second anode catalyst sub - layer 132, and a third anode catalyst sub - layer 133 with different component ratios.

[0141] In some embodiments, after forming the anode catalyst layer 13, it further includes: performing a hot pressing treatment. Through the hot pressing treatment, the bonding strength between the anode catalyst layer 13 and the first gas diffusion layer 12 can be improved.

[0142] Exemplarily, the conditions for the hot pressing treatment can be: hot pressing for 1 min - 5 min at a temperature of 120°C - 160°C and a pressure of 1 MPa - 5 MPa.

[0143] The preparation method of the cathode catalyst layer 33 is similar to that of the anode catalyst layer 13, and the only difference lies in the choice of the catalyst, which will not be elaborated here.

[0144] In some embodiments, after obtaining the composite anode layer 1, it further includes:

[0145] Activate the composite anode layer 1.

[0146] By activating the composite anode layer 1, the catalytic activity of the composite anode layer 1 can be improved, the stability can be enhanced, and the mass transfer efficiency can be optimized, etc.

[0147] Exemplarily, the method for activating the composite anode layer 1 can be: adopting cyclic voltammetry scanning in a three-electrode system, controlling the scanning potential range at 0.2V - 1.0V (relative to the reference electrode), setting the scanning rate at 5mV / s - 100mV / s, and the number of cyclic scans at 30 - 50 times.

[0148] It can be understood that in the embodiments of the present application, the preparation methods of the composite cathode layer 3 and the composite anode layer 1 are basically the same, and the main difference lies in the cathode catalyst slurry and the anode catalyst slurry. Therefore, for the preparation method of the composite cathode layer 3, the embodiments of the present application will not be specifically described in detail, and reference can be made to the preparation method of the composite anode layer 1.

[0149] In some embodiments, before laminating the composite anode layer 1, the anion exchange membrane 2, and the composite cathode layer 3 in sequence, it further includes:

[0150] Attach the anode protective layer 4 and the cathode protective layer 5 to the opposite sides of the anion exchange membrane 2 respectively.

[0151] Specifically, attaching the anode protective layer 4 and the cathode protective layer 5 to the opposite sides of the anion exchange membrane 2 respectively includes:

[0152] Provide the anode protective layer 4 and the cathode protective layer 5;

[0153] Attach the anode protective layer 4 and the cathode protective layer 5 to the opposite sides of the anion exchange membrane 2 respectively, and then perform rolling.

[0154] Among them, attaching the anode protective layer 4 and the cathode protective layer 5 to the opposite sides of the anion exchange membrane 2 respectively includes:

[0155] Vacuum adsorb the anode protective layer 4 on the first jig, vacuum adsorb the cathode protective layer 5 on the second jig, and vacuum adsorb the anion exchange membrane 2 on the third jig; then press the third jig with the vacuum-adsorbed anion exchange membrane 2 on the first jig with the vacuum-adsorbed anode protective layer 4, so that the anode protective layer 4 adheres to the anion exchange membrane 2, and then in a similar manner, attach the cathode protective layer 5 to the other side of the anion exchange membrane 2.

[0156] Exemplarily, the pressure of vacuum adsorption can be set at 0.1MPa - 3MPa.

[0157] In some embodiments, after the anode protective layer 4 and the cathode protective layer 5 are respectively attached to the opposite sides of the anion exchange membrane 2, the rolling temperature is set to 60°C - 120°C, which helps to discharge the residual bubbles and makes the adhesion between the anode protective layer 4, the anion exchange membrane 2 and the cathode protective layer 5 closer.

[0158] In some embodiments, after the composite anode layer 1, the anion exchange membrane 2 and the composite cathode layer 3 are sequentially stacked, it further includes:

[0159] Performing a thermal transfer process.

[0160] Through the thermal transfer process, the bonding tightness between the multilayer structures can be improved, ensuring the stability of the electrolytic water hydrogen production membrane electrode.

[0161] Exemplarily, during the thermal transfer process, the temperature can be set to 80°C - 150°C, the pressure can be set to 1 MPa - 10 MPa, and the processing time of the thermal transfer can be set to 10 min - 50 min.

[0162] In a third aspect, an embodiment of the present application further provides an electrolytic cell, including the electrolytic water hydrogen production membrane electrode as described above, and / or, a membrane electrode prepared by the preparation method of the electrolytic water hydrogen production membrane electrode as described above.

[0163] The electrolytic cell provided by the embodiment of the present application has all the beneficial effects of the electrolytic water hydrogen production membrane electrode as described above, which will not be elaborated herein.

[0164] Next, specific embodiments are combined to further illustrate the embodiments of the present application. It should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application. The experimental methods without specific conditions noted in the following embodiments are generally carried out according to the conditions recommended by the manufacturer.

[0165] Embodiment 1

[0166] The electrolytic water hydrogen production membrane electrode provided in this embodiment includes a composite anode layer 1, an anode protective layer 4, an anion exchange membrane 2, a cathode protective layer 5 and a composite cathode layer 3. The composite anode layer 1 includes an anode base layer 11, a first gas diffusion layer 12 and an anode catalyst layer 13. The first gas diffusion layer 12 is disposed on one side of the anode base layer 11, and the anode catalyst layer 13 is disposed on the side of the first gas diffusion layer 12 facing away from the anode base layer 11. The composite cathode layer 3 includes a cathode base layer 31, a second gas diffusion layer 32 and a cathode catalyst layer 33. The second gas diffusion layer 32 is disposed on one side of the cathode base layer 31, and the cathode catalyst layer 33 is disposed on the side of the second gas diffusion layer 32 facing away from the anode base layer 11.

[0167] The anode protective layer 4 and the cathode protective layer 5 are respectively disposed in a fitting manner on opposite sides of the anion exchange membrane 2. The composite anode layer 1 is disposed on the side of the anion exchange membrane 2 where the anode protective layer 4 is located, and the composite cathode layer 3 is disposed on the side of the anion exchange membrane 2 where the cathode protective layer 5 is located.

[0168] Among them, the material of the anode base layer 11 is nickel foam material, and the thickness is 1.0 mm. The first gas diffusion layer 12 includes a first interface layer 121, a first transition layer 122 and a first functional layer 123. The anode base layer 11, the first interface layer 121, the first transition layer 122, the first functional layer 123 and the anode catalyst layer 13 are sequentially stacked. The porosity of the first interface layer 121 is 75%, the thickness is 200 μm, the porosity of the first transition layer 122 is 55%, the thickness is 100 μm, the porosity of the first functional layer 123 is 35%, and the thickness is 50 μm. The second gas diffusion layer 32 includes a second interface layer 321, a second transition layer 322 and a second functional layer 323. The cathode base layer 31, the second interface layer 321, the second transition layer 322, the second functional layer 323 and the cathode catalyst layer 33 are sequentially stacked. The porosity of the second interface layer 321 is 75%, the thickness is 200 μm, the porosity of the second transition layer 322 is 55%, the thickness is 100 μm, the porosity of the second functional layer 323 is 35%, and the thickness is 50 μm. The anode catalyst layer 13 includes a first anode catalyst sub-layer 131, a second anode catalyst sub-layer 132 and a third anode catalyst sub-layer 133. The first gas diffusion layer 12, the first anode catalyst sub-layer 131, the second anode catalyst sub-layer 132, the third anode catalyst sub-layer 133 and the anion exchange membrane 2 are sequentially stacked along the thickness direction of the anode base layer 11. In the first anode catalyst sub-layer 131, the mass ratio of the anode catalyst is 35%, the mass ratio of the first binder is 65%. In the second anode catalyst sub-layer 132, the mass ratio of the anode catalyst is 50%, the mass ratio of the first binder is 42%, and the mass ratio of the first ionomer is 8%. In the third anode catalyst sub-layer 133, the mass ratio of the anode catalyst is 85%, and the mass ratio of the first ionomer is 15%. The cathode catalyst layer 33 includes a first cathode catalyst sub-layer 331, a second cathode catalyst sub-layer 332 and a third cathode catalyst sub-layer 333. The second gas diffusion layer 32, the first cathode catalyst sub-layer 331, the second cathode catalyst sub-layer 332, the third cathode catalyst sub-layer 333 and the anion exchange membrane 2 are sequentially stacked along the thickness direction of the cathode base layer 31. In the first cathode catalyst sub-layer 331, the mass ratio of the cathode catalyst is 35%, the mass ratio of the second binder is 65%. In the second cathode catalyst sub-layer 332, the mass ratio of the cathode catalyst is 50%, the mass ratio of the second binder is 42%, and the mass ratio of the second ionomer is 8%. In the third cathode catalyst sub-layer 333, the mass ratio of the cathode catalyst is 85%, and the mass ratio of the second ionomer is 15%. The anode catalyst in the anode catalyst layer 13 is a NiFe binary catalyst, and the thickness of the anode catalyst layer 13 is 50 μm. The cathode catalyst in the cathode catalyst layer 33 is a NiFe binary catalyst, and the thickness of the cathode catalyst layer 33 is 50 μm. The first binder and the second binder are both polytetrafluoroethylene. The first ionomer and the second ionomer are both ALkymer ionomers.

[0169] The material of the anode protective layer 4 is polytetrafluoroethylene with a thickness of 0.1 mm, and the material of the cathode protective layer 5 is polytetrafluoroethylene with a thickness of 0.1 mm.

[0170] The material of the anion exchange membrane 2 is an anion exchange membrane 2 with cyclic amine piperidine as the functional group, and the thickness is 120 μm.

[0171] Example 2

[0172] The main difference between Example 2 and Example 1 is that:

[0173] The material of the anode base layer 11 is nickel felt. Other conditions are the same as those in Example 1.

[0174] Example 3

[0175] The main difference between Example 3 and Example 1 is that:

[0176] The anode catalyst in the anode catalyst layer 13 is a NiFeCo ternary catalyst. Other conditions are the same as those in Example 1.

[0177] Example 4

[0178] The main difference between Example 4 and Example 1 is that:

[0179] The porosity of the first interface layer 121 is 80%, the thickness is 300 μm, the porosity of the first transition layer 122 is 60%, the thickness is 150 μm, and the porosity of the first functional layer 123 is 40%, the thickness is 50 μm. Other conditions are the same as those in Example 1.

[0180] Example 5

[0181] The main difference between Example 3 and Example 1 is that:

[0182] The material of the anode protective layer 4 is a perfluoroethylene propylene copolymer with a thickness of 0.1 mm, and the material of the cathode protective layer 5 is a perfluoroethylene propylene copolymer with a thickness of 0.1 mm. Other conditions are the same as those in Example 1.

[0183] Comparative Example 1

[0184] The main difference between this comparative example and Comparative Example 1 is that:

[0185] The first gas diffusion layer 12, the anode catalyst layer 13, the anion exchange membrane 2, the cathode catalyst layer 33 and the second gas diffusion layer 32 are all separately arranged, and other conditions are the same as those in the examples.

[0186] The electrolyzed water hydrogen production membrane electrodes in Examples 1 - 5 and Comparative Example 1 were respectively assembled with the anode and cathode flow fields, end plates and insulating plates into a water electrolysis cell as the test object.

[0187] The ohmic impedance, water electrolysis performance, and long-term stability of different water electrolyzers were tested separately. Among them, the test method for ohmic impedance was as follows: Using an electrochemical workstation, the constant voltage alternating current impedance of different water electrolyzers was tested at the open circuit potential, with the high frequency set to 10,000 Hz, the low frequency to 1 Hz, and the amplitude to 10 mV, and the ohmic impedance (HFR) value was recorded; the test method for water electrolysis performance was as follows: The polarization performance of different water electrolyzers was tested at 0.1 A / cm 2 , 0.2 A / cm 2 , 0.3 A / cm 2 , 0.4 A / cm 2 , 0.5 A / cm 2 , 0.6 A / cm 2 , 0.7 A / cm 2 , 0.8 A / cm 2 , 0.9 A / cm 2 , 1.0 A / cm 2 , 1.1 A / cm 2 to 1.2 A / cm 2 , and the protection condition was set to ±20 V; the test method for long-term stability was as follows: Using a 1 kW electrolyzer test device, the positive pole of the power supply was connected to the anode current collecting separator of the electrolyzer, and the negative pole of the power supply was connected to the cathode current collecting separator of the electrolyzer. The constant current (1 A / cm 2 ) test method was adopted, and the corresponding cell voltage value was recorded at intervals of every 10 s. The test operating conditions were 1 M KOH @ 60 - 65 °C, bilateral circulation, 1 A / cm 2 . The test results are shown in Table 1 and Figures 6 - 7 as follows:

[0188] Table 1 Comparison table of test results of ohmic impedance and polarization performance of different water electrolyzers

[0189] <![CDATA[HFR / Ω·cm 2 > <![CDATA[Polarization performance @ 1.2 A / cm 2 > Example 1 0.19 1.85 Example 2 0.22 1.87 Example 3 0.20 1.86 Example 4 0.19 1.84 Example 5 0.18 1.83 Comparative Example 1 0.35 1.99

[0190] As can be seen from Table 1 and Figure 6 , the water electrolyzer using the electrolyzed water hydrogen production membrane electrode in Embodiment 1 of the present application has a lower ohmic impedance and relatively better polarization performance. It shows that after the integration of the multi-in-one membrane electrode, the interlayer interface can be eliminated or simplified, effectively reducing the interface resistance, thereby improving the performance.

[0191] From Figure 7 , it can be seen that the water electrolyzer using the electrolyzed water hydrogen production membrane electrode in Embodiment 1 of the present application has better stability. It shows that during the long-term operation of this electrolyzed water hydrogen production membrane electrode, the impedance rise and performance decay caused by chemical corrosion or mechanical stress at the interface can be effectively avoided. The reduction of the interface improves the structural stability, and the durability of the electrolyzer is better.

[0192] The above has introduced the embodiments of the present application in detail. Specific examples are used in this text to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A membrane electrode for producing hydrogen by electrolysis of water, characterized in that: include: A composite anode layer, the composite anode layer comprising an anode base layer, a first gas diffusion layer and an anode catalyst layer, the first gas diffusion layer being arranged on one side of the anode base layer, and the anode catalyst layer being arranged on a side of the first gas diffusion layer away from the anode base layer; An anion exchange membrane is disposed on a side of the composite anode layer having the anode catalyst layer; A composite cathode layer is arranged on the side of the anion exchange membrane away from the composite anode layer, and the composite cathode layer includes a cathode base layer, a second gas diffusion layer and a cathode catalyst layer, the second gas diffusion layer is arranged on one side of the cathode base layer, the cathode catalyst layer is arranged on the side of the second gas diffusion layer away from the anode base layer, and the cathode catalyst layer is arranged close to the anion exchange membrane.

2. The water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The thickness of the anion exchange membrane is 20 μm-150 μm.

3. The water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The material of the anode base layer includes at least one of foamed nickel and nickel felt.

4. The water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The first gas diffusion layer comprises a first interface layer, a first transition layer and a first functional layer, and the anode base layer, the first interface layer, the first transition layer, the first functional layer and the anode catalyst layer are sequentially stacked along the thickness direction of the anode base layer; The porosity of the first interface layer is P1, the porosity of the first transition layer is P2, and the porosity of the first functional layer is P3, satisfying: P1>P2>P3.

5. The water electrolysis hydrogen production membrane electrode according to claim 4, characterized in that: The porosity P1 of the first interface layer is 70%-80%; and / or, the porosity P2 of the first transition layer is 50%-60%; And / or, the porosity P3 of the first functional layer is 30%-40%.

6. The membrane electrode for producing hydrogen by electrolysis of water according to claim 4, characterized in that: The thickness of the first interface layer is 100 μm-300 μm; And / or, the thickness of the first transition layer is 50 μm-150 μm; And / or, the thickness of the first functional layer is 20 μm-50 μm.

7. The water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The material of the cathode base layer includes at least one of a carbon fiber material, a porous ceramic material and a carbon fiber composite material reinforced by carbon nanotubes.

8. The water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The second gas diffusion layer comprises a second interface layer, a second transition layer and a second functional layer, and the cathode base layer, the second interface layer, the second transition layer, the second functional layer and the cathode catalyst layer are sequentially stacked along the thickness direction of the cathode base layer; The porosity of the second interface layer is P4, the porosity of the second transition layer is P5, and the porosity of the second functional layer is P6, satisfying: P4>P5>P6.

9. The water electrolysis hydrogen production membrane electrode according to claim 8, characterized in that: The porosity P4 of the second interface layer is 70%-80%; and / or, the porosity P5 of the second transition layer is 50%-60%; And / or, the porosity P6 of the second functional layer is 30%-40%.

10. The membrane electrode for producing hydrogen by electrolysis of water according to claim 8, characterized in that: The thickness of the second interface layer is 100 μm-300 μm; And / or, the thickness of the second transition layer is 50 μm-150 μm; And / or, the second functional layer has a thickness of 20 μm-50 μm.

11. The membrane electrode for producing hydrogen by electrolysis of water according to claim 1, characterized in that: The anode catalyst layer includes a first anode catalyst sublayer, a second anode catalyst sublayer and a third anode catalyst sublayer; The first gas diffusion layer, the first anode catalyst sublayer, the second anode catalyst sublayer, the third anode catalyst sublayer and the anion exchange membrane are stacked in sequence along the thickness direction of the anode base layer; The mass ratio of the anode catalyst in the first anode catalyst sublayer is A1, the mass ratio of the anode catalyst in the second anode catalyst sublayer is A2, and the mass ratio of the anode catalyst in the third anode catalyst sublayer is A3, A1<A2<A3; The mass ratio of the first adhesive in the first anode catalyst sublayer is B1, the mass ratio of the first adhesive in the second anode catalyst sublayer is B2, and the mass ratio of the first adhesive in the third anode catalyst sublayer is B3, B1>B2>B3.

12. The membrane electrode for producing hydrogen by electrolysis of water according to claim 11, characterized in that: In the first anode catalyst sublayer, the mass ratio of the anode catalyst is 30%-40%, and the mass ratio of the first adhesive is 60%-70%; And / or, in the second anode catalyst sublayer, the mass ratio of the anode catalyst is 40%-60%, the mass ratio of the first binder is 30%-55%, and the mass ratio of the first ionomer is 5%-10%; And / or, in the third anode catalyst sublayer, the mass ratio of the anode catalyst is 80%-90%, and the mass ratio of the first ionomer is 10%-20%.

13. The membrane electrode for producing hydrogen by electrolysis of water according to claim 1, characterized in that: The cathode catalyst layer includes a first cathode catalyst sublayer, a second cathode catalyst sublayer and a third cathode catalyst sublayer; The second gas diffusion layer, the first cathode catalyst sublayer, the second cathode catalyst sublayer, the third cathode catalyst sublayer and the anion exchange membrane are sequentially stacked along the thickness direction of the cathode base layer; The mass ratio of the cathode catalyst in the first cathode catalyst sublayer is A4, the mass ratio of the cathode catalyst in the second cathode catalyst sublayer is A5, and the mass ratio of the cathode catalyst in the third cathode catalyst sublayer is A6, A4<A5<A6; The mass ratio of the second adhesive in the first cathode catalyst sublayer is B4, the mass ratio of the second adhesive in the second cathode catalyst sublayer is B5, and the mass ratio of the second adhesive in the third cathode catalyst sublayer is B6, B4>B5>B6.

14. The membrane electrode for producing hydrogen by electrolysis of water according to claim 13, characterized in that: In the first cathode catalyst sublayer, the mass ratio of the cathode catalyst is 30%-40%, and the mass ratio of the second adhesive is 60%-70%; And / or, in the second cathode catalyst sublayer, the mass ratio of the cathode catalyst is 40%-60%, the mass ratio of the second adhesive is 30%-55%, and the mass ratio of the second ionomer is 5%-10%; And / or, in the third cathode catalyst sublayer, the mass ratio of the cathode catalyst is 80%-90%, and the mass ratio of the second ionomer is 10%-20%.

15. The membrane electrode for producing hydrogen by electrolysis of water according to any one of claims 1 to 14, characterized in that: The water electrolysis hydrogen production membrane electrode also includes an anode protection layer, which is arranged between the composite anode layer and the anion exchange membrane, and the anode protection layer is arranged on the surface of the anion exchange membrane; And / or, the water electrolysis hydrogen production membrane electrode further includes a cathode protection layer, the cathode protection layer is arranged between the composite cathode layer and the anion exchange membrane, and the cathode protection layer is adhered to the surface of the anion exchange membrane.

16. The membrane electrode for producing hydrogen by electrolysis of water according to claim 15, characterized in that: The thickness of the anode protection layer is 0.01 mm-0.1 mm; And / or, the thickness of the cathode protection layer is 0.01 mm-0.1 mm.

17. The membrane electrode for producing hydrogen by electrolysis of water according to claim 15, characterized in that: The material of the anode protection layer includes at least one of fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyethylene terephthalate, polyimide and polyphenylene sulfide; And / or, the material of the cathode protection layer includes at least one of fluorinated ethylene propylene copolymer, polytetrafluoroethylene, polyethylene terephthalate, polyimide and polyphenylene sulfide.

18. A method for preparing a membrane electrode for producing hydrogen by electrolysis of water, characterized in that: include: Coating a first gas diffusion layer slurry on one side of the anode base layer to form a first gas diffusion layer; Coating an anode catalyst slurry on a side of the first gas diffusion layer away from the anode base layer to form an anode catalyst layer to obtain a composite anode layer; Coating a second gas diffusion layer slurry on one side of the cathode base layer to form a second gas diffusion layer; Coating a cathode catalyst slurry on a side of the second gas diffusion layer away from the cathode base layer to form a cathode catalyst layer to obtain a composite cathode layer; The composite anode layer, the anion exchange membrane and the composite cathode layer are stacked in sequence to obtain a water electrolysis hydrogen production membrane electrode; The anion exchange membrane is arranged on the side of the composite anode layer having the anode catalyst layer, the composite cathode layer is arranged on the side of the anion exchange membrane away from the composite anode layer, and the cathode catalyst layer is arranged close to the anion exchange membrane.

19. The method for preparing a membrane electrode for producing hydrogen by electrolysis of water according to claim 18, characterized in that: The method of coating a first gas diffusion layer slurry on one side of the anode base layer comprises: Spraying the first gas diffusion layer slurry on one side of the anode base layer, with the spraying pressure set to 0.3 MPa-0.5 MPa and the slurry flow rate set to 50 mL / min-100 mL / min; Then, hot pressing is performed at a temperature of 100°C-200°C and a pressure of 5MPa-15MPa for 10min-30min.

20. The method for preparing a membrane electrode for producing hydrogen by electrolysis of water according to claim 18, characterized in that: After obtaining the composite anode layer, the method further comprises: The composite anode layer is activated.

21. An electrolytic cell, characterized in that: It comprises the membrane electrode for producing hydrogen by electrolysis of water as described in any one of claims 1 to 17, and / or a membrane electrode produced by the method for producing hydrogen by electrolysis of water as described in any one of claims 18 to 20.

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