Electrolytic bath

Abstract

The utility model provides an electrolytic bath. The electrolytic bath comprises a film layer, the anode catalyst layer is formed on one side of the film layer, the anode catalyst layer comprises a hydrogen consumption layer and an anode catalyst base layer, the hydrogen consumption layer is formed between the film layer and the anode catalyst base layer, and the hydrogen consumption layer is provided with a bending structure; the cathode catalyst layer is formed on one side of the film layer; the two polar plates are respectively positioned on the outer sides of the anode catalyst layer and the cathode catalyst layer; wherein the bending structure of the hydrogen consumption layer is consistent with the flow field distribution of the polar plate on the outer side of the cathode catalyst layer. Therefore, according to the application, the removal efficiency of hydrogen on the anode side can be improved, meanwhile, the usage amount of the dehydrogenation catalyst is reduced, and the cost is reduced.

Description

[0001] This application is a divisional application. The application number of the original application is 202421471546.0, and the original application date is June 26, 2024. The entire content of the original application is incorporated herein by reference. Technical Field

[0002] The utility model relates to the technical field of electrode preparation, and particularly to an electrolytic cell. Background Art

[0003] As the core component of the water electrolysis hydrogen production technology, the membrane electrode is composed of an electrode catalyst layer, an electrode catalyst layer and a membrane layer, and plays roles such as conducting protons, catalyzing reactions and separating gases, and determines the performance, efficiency, life and cost of water electrolysis hydrogen production.

[0004] However, in the membrane electrode, the electrode catalyst layer and the membrane layer are prone to peeling, and the stability of the membrane electrode is poor. At the same time, during the electrolysis process, hydrogen can permeate from the cathode to the anode through the membrane layer, and the mixing of hydrogen and oxygen will reduce the performance of the membrane electrode, and in severe cases, it will cause an explosion, and the safety problem is prominent. Summary of the Utility Model

[0005] In view of the above-mentioned disadvantages of the prior art, the purpose of the present utility model is to provide an electrolytic cell, which can improve the removal efficiency of hydrogen on the anode side, reduce the usage amount of hydrogen-consuming catalyst at the same time, and reduce costs.

[0006] To solve the above technical problems, the present utility model is realized through the following technical solutions.

[0007] The present utility model provides an electrolytic cell, comprising:

[0008] A membrane layer;

[0009] An anode catalyst layer formed on one side of the membrane layer, the anode catalyst layer includes a hydrogen consumption layer and an anode catalyst base layer, the hydrogen consumption layer is formed between the membrane layer and the anode catalyst base layer, and the hydrogen consumption layer is provided with a bending structure; and

[0010] A cathode catalyst layer formed on one side of the membrane layer;

[0011] Bipolar plates located outside the anode catalyst layer and the cathode catalyst layer respectively;

[0012] Wherein the bending structure of the hydrogen consumption layer is consistent with the flow field distribution of the plate outside the cathode catalyst layer.

[0013] In an embodiment of the present utility model, the hydrogen consumption layer includes a plurality of arranged strip-shaped structures.

[0014] In one embodiment of the present utility model, at one end closer to the water flow direction, the widths of the strip-shaped structures of the hydrogen consumption layer increase successively.

[0015] In one embodiment of the present utility model, at one end closer to the water flow direction, the thickness of the hydrogen consumption layer increases.

[0016] In one embodiment of the present utility model, at one end closer to the water flow direction, the densities of the hydrogen-consuming catalysts in the hydrogen consumption layer increase successively.

[0017] In one embodiment of the present utility model, a part of the hydrogen consumption layer of the anode catalyst layer is embedded or fused into the membrane layer.

[0018] In one embodiment of the present utility model, the thickness ratio of the membrane layer, the anode catalyst layer, and the cathode catalyst layer is 1:0.1:0.1 to 1:10:10.

[0019] In one embodiment of the present utility model, the thickness ratio of the hydrogen consumption layer to the anode catalyst base layer is 1:1 to 1:10.

[0020] In one embodiment of the present utility model, the porosity of the hydrogen consumption layer is 100 - 330 m 2 / g;

[0021] And / or, the porosity of the anode catalyst base layer is 100 - 330 m 2 / g;

[0022] And / or, the porosity of the cathode catalyst layer is 100 - 330 m 2 / g.

[0023] In one embodiment of the present utility model, the electrolytic cell is a proton exchange membrane electrolytic cell, an anion exchange membrane electrolytic cell, an alkaline solution electrolytic cell, or a solid oxide electrolytic cell.

[0024] In summary, the present utility model provides a membrane electrode and a hydrogen production electrolytic cell, which can improve the removal efficiency of hydrogen on the anode side, reduce the usage amount of the hydrogen-consuming catalyst, and lower the cost.

[0025] Of course, it is not necessary to achieve all the above advantages simultaneously when implementing any aspect of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 Schematic flow chart of the preparation method of the membrane electrode in an embodiment of the present utility model.

[0028] Figure 2 Physical diagram of the membrane electrode in an embodiment of the present utility model.

[0029] Figure 3 For Figure 2 Cross-sectional micrograph of the membrane electrode in

[0030] Figure 4 For Figure 3 Magnified view of the membrane layer and the electrode catalyst layer in

[0031] Figure 5 For Figure 2 Stability curve diagram of the membrane electrode in

[0032] Figure 6 Schematic diagram of the membrane layer and the electrode catalyst layer in an embodiment of the present utility model.

[0033] Figure 7 Micrograph of the membrane layer and the electrode catalyst layer in an embodiment of the present utility model.

[0034] Figure 8 Schematic structural diagram of the membrane electrode in an embodiment of the present utility model.

[0035] Figure 9 Schematic diagram of the distribution of the hydrogen consumption layer on the membrane layer in an embodiment of the present utility model.

[0036] Figure 10 Schematic diagram of the flow channel in the cathode catalyst layer in an embodiment of the present utility model.

[0037] Figure 11 Schematic diagram of the distribution of the hydrogen consumption layer on the membrane layer in another embodiment of the present utility model.

[0038] Figure 12 Schematic structural diagram of the membrane electrode during transfer in an embodiment of the present utility model.

[0039] Figure 13 SEM image of the electrode catalyst layer obtained by the transfer method of the present utility model in an embodiment.

[0040] Figure 14 SEM image of the conventionally obtained electrode catalyst layer. Detailed implementation manners

[0041] The following describes the implementation modes of the present utility model through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present utility model from the content disclosed in this specification. The present utility model can also be implemented or applied through other different specific implementation modes. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present utility model. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0042] It should be understood that the present utility model can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present utility model to those skilled in the art.

[0043] The technical solutions of the present utility model will be further described in detail below in conjunction with the embodiments and the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts fall within the scope of protection of the present utility model.

[0044] Please refer to Figure 1 As shown, the present utility model provides a method for preparing a membrane electrode, which at least includes steps S11 - S15.

[0045] S11. Provide a membrane layer, the membrane layer including a first surface and a second surface arranged opposite to each other.

[0046] S12. Coat the precursor solution on the first surface.

[0047] S13. Coat the adhesion enhancer on the precursor solution.

[0048] S14. Place the membrane layer in an alkaline solution for growth to in-situ grow an electrode catalyst layer on the first surface.

[0049] S15. Repeat the above steps for the second surface using the precursor solution, the adhesion enhancer, and the alkaline solution to in-situ grow another electrode catalyst layer on the second surface to obtain a membrane electrode.

[0050] Please refer to Figure 1As shown, in an embodiment of the present utility model, in step S11, the film layer 100 is, for example, a diaphragm, a cation exchange membrane, an anion exchange membrane, a proton exchange membrane, a porous membrane, or other film layers that can be used for hydrogen production electrolysis. The film layer 100, for example, includes a first surface and a second surface that are oppositely arranged. Further, before use, the film layer 100 needs to be pretreated to remove impurities on the first surface and the second surface, so that the film layer 100 can be closely attached to the subsequent formed electrode catalyst layer 200 and electrode catalyst layer 300. In an embodiment of the present utility model, the pretreatment, for example, includes soaking the film layer 100 in a solvent at a preset temperature for a preset time, then taking out the film layer 100 and rinsing it with deionized water, and then putting it into an oven for drying. Among them, the solvent is, for example, at least one of hydrogen peroxide and sulfuric acid, etc., the preset temperature is, for example, 50°C - 90°C, and the preset time is, for example, 0.5h - 5h.

[0051] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after providing the film layer 100, before coating the precursor solution in step S12, the precursor solution also needs to be homogenized to obtain a uniform precursor solution. Among them, the method of homogenization treatment, for example, includes ultrasonic stirring treatment of the precursor solution, and the ultrasonic stirring time is, for example, 1min - 2h. In this embodiment, the precursor solution, for example, includes a metal compound and a solution. Among them, the metal compound is, for example, selected from at least two of transition metal compounds, rare earth metal compounds, and noble metal compounds. The transition metal compound, for example, includes metal compounds such as manganese, chromium, iron, cobalt, nickel, copper, zinc, molybdenum, or tungsten, etc. The rare earth metal compound, for example, includes lanthanide rare earth metal compounds, etc. The noble metal compound, for example, includes platinum group noble metal compounds, etc. In this embodiment, the metal compound is, for example, a metal salt or a metal halide, etc. The metal salt is, for example, a metal sulfate, a metal nitrate, or a metal chromate, etc. The solvent, for example, includes at least one of alcohol solvents such as ethanol, ethylene glycol, propanol, and isopropyl alcohol, etc.

[0052] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after homogenizing the precursor solution, in step S12, the precursor solution is coated on the first surface. Among them, the method of coating the precursor solution on the first surface, for example, adopts any one of soaking or ultrasonic spraying, etc. Specifically, when the soaking method is adopted, first, glue is coated on the second surface and the second surface is dried to form a protective layer on the second surface, and then the film layer 100 with the protective layer is soaked in the precursor solution. Among them, the glue is, for example, at least one of epoxy resin, acrylic modified epoxy resin, and perfluorosulfonic acid resin, etc. By coating glue on the second surface to form a protective layer, it can avoid the attachment of the precursor solution on the second surface, so that the electrode catalyst layer 200 can be accurately formed on the first surface.

[0053] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after coating the precursor solution on the first surface, in step S13, the adhesion enhancer is coated on the precursor solution. Among them, the adhesion enhancer is, for example, selected from at least one of potassium borohydride, sodium borohydride, glucose, methanol, diisobutylaluminum hydride, ascorbic acid, hydrazine, sodium sulfite, etc. The method of coating the adhesion enhancer on the precursor solution includes, for example, any one of immersion or ultrasonic spraying. When the precursor solution is coated on the first surface by immersion in step S12, in step S13, the adhesion enhancer can be added to the precursor solution, and the film layer 100 is continuously immersed in the precursor solution containing the adhesion enhancer.

[0054] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after coating the adhesion enhancer on the precursor solution, in step S14, the film layer 100 with the adhesion enhancer and the precursor solution is immersed in an alkaline solution for growth. Among them, the pH of the alkaline solution is, for example, 8 - 14, and the alkaline solution is, for example, selected from at least one of alkaline solutions such as sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate, and potassium bicarbonate. The temperature of the alkaline solution is, for example, 30°C - 90°C, and the immersion time of the film layer 100 in the alkaline solution is, for example, 5 min - 1200 min.

[0055] Please refer to Figure 1 As shown, in an embodiment of the present utility model, in step S14, during the process of immersing the film layer 100 in the alkaline solution, the precursor solution coated on the film layer 100 grows in-situ on the first surface to form the electrode catalyst layer 200. Moreover, during the in-situ growth process, the adhesion enhancer coated on the precursor solution can enhance the adhesion between the electrode catalyst layer 200 and the film layer 100, enabling the electrode catalyst layer 200 and the film layer 100 to be closely adhered, thereby improving the stability of the membrane electrode.

[0056] Please refer to Figure 1 As shown, in an embodiment of the present utility model, after completing step S14, that is, after the immersion of the film layer 100 in the alkaline solution is completed, the film layer 100 needs to be taken out of the alkaline solution and rinsed to remove the alkaline solution adhering to the first surface. Among them, the solvent for rinsing the film layer 100 includes, for example, at least one of deionized water and alcohol reagents. Further, when steps S12 and S13 use the immersion method to coat the precursor solution and the adhesion enhancer on the first surface, before rinsing the film layer 100, the protective layer on the second surface also needs to be removed.

[0057] Please refer to Figure 1As shown, in an embodiment of the present invention, after rinsing the membrane layer 100, in step S15, a precursor solution, a binding force enhancer, and an alkaline solution are used to repeat steps S12 - S14 on the second surface to in-situ grow an electrode catalyst layer 300 on the second surface. Specifically, the precursor solution is coated on the second surface, and then after coating the binding force enhancer on the precursor solution, the membrane layer 100 is placed in the alkaline solution for growth. After the growth is completed, the membrane layer 100 is taken out of the alkaline solution and rinsed. Among them, compared with the formation process of the electrode catalyst layer 200, the difference in the formation process of the electrode catalyst layer 300 is that in the precursor solution, transition metal compounds include metal compounds such as manganese, chromium, iron, cobalt, nickel, copper, or zinc, etc., and the rest are exactly the same, so no more elaboration will be made here.

[0058] Please refer to Figure 1 As shown, in an embodiment of the present invention, after forming the electrode catalyst layer 300 on the second surface and rinsing the membrane layer 100, the membrane layer 100 also needs to be dried to obtain a membrane electrode. Among them, the membrane layer 100 is, for example, vacuum-dried, and the temperature for vacuum-drying the membrane layer 100 is, for example, 50°C - 150°C. In the preparation method provided by the present invention, in the alkaline solution, the precursor solution and the precursor solution are respectively in-situ grown on the first surface and the second surface of the membrane layer 100 to form an electrode catalyst layer 200 on the first surface of the membrane layer 100 and an electrode catalyst layer 300 on the second surface of the membrane layer 100. Moreover, during the in-situ growth process, the binding force enhancer on the precursor solution and the precursor solution can enhance the binding force between the electrode catalyst layer 200 and the first surface, as well as the binding force between the electrode catalyst layer 300 and the second surface, so as to improve the quality and stability of the membrane electrode. Moreover, the preparation method provided by the present invention can simplify the preparation process of the membrane electrode, reduce the preparation cycle and cost, and is suitable for large-scale production of the membrane electrode.

[0059] Please refer to Figure 1As shown, the present utility model also provides a membrane electrode, which is obtained by the above-mentioned preparation method of the membrane electrode. The membrane electrode includes, for example, a membrane layer 100, an electrode catalyst layer 200, an electrode catalyst layer 300, etc. Among them, the membrane layer 100 includes a first surface and a second surface arranged oppositely. The electrode catalyst layer 200 is, for example, arranged on the first surface, and the electrode catalyst layer 300 is, for example, arranged on the second surface. In the membrane electrode provided by the present utility model, in an alkaline solution, the precursor solution grows in-situ on the first surface or the second surface to form the electrode catalyst layer 200 or the electrode catalyst layer 300. Moreover, during the in-situ growth process, the binding force enhancer can enhance the binding force between the electrode catalyst layer 200 and the first surface, and between the electrode catalyst layer 300 and the second surface, so that the membrane layer 100 and the electrode catalyst layer are tightly combined, and the electrode catalyst layer and the membrane layer 100 are not easily peeled off, thereby improving the stability of the membrane electrode and the utilization rate of the catalyst in the electrode catalyst layer, and improving the efficiency of hydrogen production by water electrolysis.

[0060] Please refer to Figures 1 to 2 As shown, in an embodiment of the present utility model, a membrane electrode is obtained according to the preparation method of the membrane electrode. The physical diagram of the membrane electrode is as Figure 2 shown.

[0061] Please refer to Figures 3 to 4 As shown, in an embodiment of the present utility model, for Figure 2 the membrane electrode in is characterized. For example, the cross-section of the membrane electrode is characterized by a scanning electron microscope, and the area between the electrode catalyst layer 200 and the membrane layer 100 is magnified. Among them, Figure 3 the magnification of is, for example, 100 times, Figure 4 the magnification of is, for example, 400 times. Combining Figure 3 and Figure 4 it can be known that in the membrane electrode, the electrode catalyst layer 300 and the electrode catalyst layer 200 are respectively located on both sides of the membrane layer 100. Moreover, there is a fusion region 201 between the electrode catalyst layer 200 and the membrane layer 100. In the fusion region 201, the electrode catalyst layer 200 grows on the membrane layer 100 and diffuses in the direction of the membrane layer 100. At this time, part of the electrode catalyst layer 200 can be embedded or fused into the membrane layer 100. The membrane layer 100 and the electrode catalyst layer 200 are tightly combined and have better binding stability. In some embodiments, the depth of the electrode catalyst layer 200 embedded in the membrane layer 100 is, for example, 10 nm to 7 μm.

[0062] It should be noted that, through the method of the present application, the electrode catalyst layers 200 can be directly grown on the opposite sides of the membrane layer 100 respectively to form the membrane electrode of the electrolytic cell. However, it is not limited thereto. In some embodiments, through the method of the present application, the electrode catalyst layer 200 can also be grown only on one side of the membrane layer 100, and on the other side of the membrane layer 100, the electrode catalyst can be formed on the diffusion layer. That is, in the membrane electrode of the present application, the electrode catalyst layer 200 can be formed on one side or both opposite sides of the membrane layer 100. For example, in the AEM membrane electrode, the electrode catalyst layer 200 can be formed on one side of the membrane layer 100, and the other electrode catalyst layer 200 can be formed on the diffusion layer.

[0063] Please refer to Figure 5 As shown, in an embodiment of the present invention, the stability of the membrane electrode in Figure 2 is characterized. Specifically, the membrane electrode is loaded to a preset current density, and the change of the voltage of the membrane electrode within 100 h is measured. Among them, the preset current density is, for example, 2 A / cm 2 . From Figure 5 , it can be seen that within 0 - 70 h, the voltage of the membrane electrode fluctuates stably around 1.94 V and tends to 1.94 V. Therefore, the stability of the membrane electrode is relatively good.

[0064] Please refer to Figure 6 and Figure 7 As shown, in an embodiment of the present invention, on the anode side of the membrane layer 100, the electrode catalyst layer 300 can include a first metal catalyst layer 301 and a second metal catalyst layer 302. The first metal catalyst layer 301 is formed on the membrane layer 100 and can partially penetrate or embed into the membrane layer 100. The second metal catalyst layer 302 is formed on the first metal catalyst layer 301. The first metal catalyst layer 301 and the second metal catalyst layer 302 can have different metal catalysts. For example, the first metal catalyst layer 301 can include a platinum metal catalyst, and the second metal catalyst layer 302 can include an iridium or iridium oxide metal catalyst. By using different metal catalysts, the usage load of precious metal (such as iridium) catalysts can be reduced, thereby reducing costs.

[0065] In one embodiment, the thickness of the first metal catalyst layer 301 is, for example, 5 nm to 200 nm, and the thickness of the second metal catalyst layer 302 is, for example, 50 nm to 5 μm.

[0066] In one embodiment, the nanoparticle size of the metal catalyst in the first metal catalyst layer 301 is, for example, 1 nm to 15 nm, and the nanoparticle size of the metal catalyst in the second metal catalyst layer 302 is, for example, 10 nm to 200 nm.

[0067] Please refer to Figure 8As shown, in another embodiment of the present utility model, the membrane electrode provided by the present utility model includes a membrane layer 100, an anode catalyst layer 11, a cathode catalyst layer 12, etc. The anode catalyst layer 11 and the cathode catalyst layer 12 are respectively formed on both sides of the membrane layer 100. The anode catalyst layer 11 includes a hydrogen consumption layer 111 and an anode catalyst base layer 112. The hydrogen consumption layer 11 is formed between the membrane layer 100 and the anode catalyst base layer 113. By providing the hydrogen consumption layer 11, the hydrogen permeating from the cathode side to the anode can be eliminated in time, the purity of the gas can be improved, and the safety of the water electrolysis hydrogen production device can be improved.

[0068] Please refer to Figure 8 As shown, in one embodiment of the present utility model, the membrane layer 100 is, for example, an N115 proton membrane, etc., and the thickness of the membrane layer 100 is, for example, 110 μm to 130 μm, etc. The thickness of the N115 proton membrane is, for example, 127 μm to meet conduction, isolation, and thermal stability, etc.

[0069] Please refer to Figure 8 As shown, in one embodiment of the present utility model, the hydrogen-consuming catalyst in the hydrogen consumption layer 111 is, for example, selected from high-activity, acid-resistant, and highly stable materials such as Pt, Ir, or Pd. The anode catalyst in the anode catalyst base layer 112 is, for example, a catalyst for catalyzing oxygen reactions, and is also, for example, selected from at least one of Ir, IrO2, Pt, Pd, or Ru. Through the hydrogen-consuming catalyst in the hydrogen consumption layer 11, the hydrogen-consuming catalyst in the hydrogen consumption layer 11 can convert the hydrogen diffused from the cathode into hydrogen ions. A part of the oxygen generated on the anode side will diffuse into the hydrogen consumption layer 111. The hydrogen-consuming catalyst in the hydrogen consumption layer 111 can also convert the oxygen diffused into the hydrogen consumption layer 11 into oxygen ions, so that hydrogen ions and oxygen ions react to form water, so as to react hydrogen and oxygen to obtain water, thereby achieving the purpose of eliminating hydrogen on the anode side, improving the purity of oxygen on the anode side, and at the same time preventing oxygen from diffusing to the cathode, that is, it can improve the purity of both hydrogen and oxygen generated by water electrolysis and improve the safety of the water electrolysis device.

[0070] Please refer to Figure 8 As shown, in one embodiment of the present utility model, the cathode catalyst in the cathode catalyst layer 12 is, for example, a catalyst for catalyzing hydrogen reactions, and is also, for example, selected from at least one of Ir, IrO2, Pt / C, Pt, Pd, or Ru.

[0071] Please refer to Figure 8As shown, in an embodiment of the present utility model, the thickness ratios of the membrane layer 100, the anode catalyst layer 11, and the cathode catalyst layer 12 are, for example, 1:0.1:0.1 to 1:10:10, and for another example, 1:1.5:1.5, etc. Moreover, the thickness ratios of the hydrogen consumption layer 111 and the anode catalyst base layer 112 are, for example, 1:1 to 1:10, 1:5, etc. In a specific embodiment of the present utility model, the total thickness of the membrane electrode is, for example, 154 μm. When the membrane electrode is within this thickness range and the thicknesses of different layers are coordinated, the efficiency of electrolyzing water by the membrane electrode can be improved.

[0072] Please refer to Figure 8 As shown, in an embodiment of the present utility model, the porosity of the hydrogen consumption layer 111 is, for example, 1 m 2 / g, the porosity of the anode catalyst base layer 112 is, for example, 100 - 330 m 2 / g, and the porosity of the cathode catalyst layer 12 is, for example, 100 - 330 m 2 / g. In a specific embodiment of the present utility model, the porosity of the hydrogen consumption layer 111 is, for example, 130 m 2 / g, the porosity of the anode catalyst base layer 112 is, for example, 160 m 2 / g, and the porosity of the cathode catalyst layer 12 is, for example, 180 m 2 / g. Among them, the porosities of the anode catalyst layer 11 and the cathode catalyst layer 12 on both sides of the membrane layer 100 are relatively large, which can increase the number of pores in the membrane electrode, provide abundant pores for mass transfer, and thus improve the electrolysis rate.

[0073] Please refer to Figure 9 As shown, in an embodiment of the present utility model, a distribution schematic diagram of the hydrogen consumption layer 111 on the membrane layer 100 is provided. During the electrolysis process, the hydrogen permeating through the membrane layer 100 gradually accumulates from the inlet to the outlet of the anode layer flow field. In some embodiments, the loading amount of the hydrogen consumption layer can increase along the water flow direction of the anode catalyst layer. Therefore, on the anode side of the membrane layer 100, from the end of the membrane electrode far away from the water flow direction to the end close to the water flow direction, the hydrogen consumption layer 111 on the membrane layer 100 increases, such as by increasing the width, loading amount, and density of the hydrogen-consuming catalyst of the hydrogen consumption layer 111, etc. In Figure 9 part a, the hydrogen consumption layer 111 includes multiple arranged strip-shaped structures, and towards the end close to the water flow direction, the widths of the strip-shaped structures of the hydrogen consumption layer 111 increase in sequence. In Figure 9 part b, towards the end close to the water flow direction, the loading amounts of the hydrogen consumption layer 111 increase in sequence, such as by increasing the thickness of the hydrogen consumption layer 111. In Figure 9In part c, at one end closer to the water flow direction, the density of the hydrogen-consuming catalyst in the hydrogen consumption layer 111 increases successively. By setting different amounts of the hydrogen consumption layer 111 in different regions of the membrane layer 100, the removal efficiency of hydrogen on the anode side can be improved, while reducing the usage amount of the hydrogen-consuming catalyst and lowering the cost.

[0074] Please refer to Figure 10 and Figure 11 As shown, in another embodiment of the present invention, a schematic diagram of the distribution of the hydrogen consumption layer 111 on the membrane layer 100 is provided. The electrolytic cell includes a membrane electrode 10 and bipolar plates 20, and the bipolar plates 20 are respectively located outside the anode catalytic layer and the cathode catalytic layer of the membrane electrode. During electrolysis, due to the pressure on the membrane layer 100 at the contact part between the position of the cathode flow field ridge 201 of the plate 20 on the cathode catalytic layer side and the membrane layer 100, it is not conducive to hydrogen permeation, and the hydrogen content is low. The membrane layer 100 at the position of the flow channel 202 swells and has more microporous channels, which is conducive to hydrogen permeation. In some embodiments, the hydrogen consumption layer 111 may be provided with a bending structure (such as Figure 11 shown), and the bending structure of the hydrogen consumption layer 111 may be consistent with the flow field distribution of the plate outside the cathode catalytic layer. It can consume the hydrogen diffused from the flow channel 202, improve the removal efficiency of hydrogen on the anode side, and improve the safety of electrolysis.

[0075] In one embodiment of the present invention, the present invention also provides a preparation method of a membrane electrode, including steps S11 - S12.

[0076] Step S11: Form an anode catalytic layer on one side of the membrane layer. The anode catalytic layer includes a hydrogen consumption layer and an anode catalytic base layer, and the hydrogen consumption layer is formed between the membrane layer and the anode catalytic base layer.

[0077] Step S12: Form a cathode catalytic layer on the other side of the membrane layer.

[0078] In one embodiment of the present invention, the electrode catalytic layer (anode catalytic layer and / or cathode catalytic layer) can be formed, for example, by a transfer method. When performing transfer, the anode catalytic layer and the cathode catalytic layer can be transferred simultaneously or step by step. The hydrogen consumption layer and the anode catalytic base layer in the anode catalytic layer can be transferred simultaneously or step by step. When transferred synchronously, an anode catalytic base layer is formed on the transfer membrane, and after forming the hydrogen consumption layer on the anode catalytic base layer, it is transferred to the membrane layer. When transferred step by step, first transfer the hydrogen consumption layer to the membrane layer, and then transfer the anode catalytic base layer to the anode catalytic base layer. In this embodiment, for example, a non-vacuum hot press transfer method is used for transfer.

[0079] Please refer to Figure 12As described above, in an embodiment of the present invention, an anodic catalytic slurry layer and a hydrogen-consuming slurry layer are formed on a transfer film to form a first transfer film 15. Among them, the anodic catalytic slurry layer includes an anodic catalyst and a resin, etc. The anodic catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the anodic catalyst to the resin is, for example, 1:0.1 to 1:3. The anodic catalytic slurry layer is formed, for example, by knife coating, roll coating or spraying. The hydrogen-consuming slurry layer includes a hydrogen-consuming catalyst and a resin, etc. The hydrogen-consuming catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the hydrogen-consuming catalyst to the resin is, for example, 1:0.5 to 1:3. The hydrogen-consuming slurry layer is formed, for example, by knife coating, roll coating or spraying.

[0080] Please refer to Figure 12 As described above, in an embodiment of the present invention, a cathodic catalytic slurry layer is formed on a transfer film to form a second transfer film 16. Among them, the cathodic catalytic slurry layer includes a cathodic catalyst and a resin, etc. The cathodic catalyst includes a carrier and a component containing an active metal element substance loaded on the carrier. The mass ratio of the cathodic catalyst to the resin is, for example, 1:0.7 to 1:2. The cathodic catalytic slurry layer is formed, for example, by knife coating, roll coating or spraying.

[0081] In an embodiment of the present invention, the resins in the anodic catalytic slurry layer, the hydrogen-consuming slurry layer and the cathodic catalytic slurry layer may be the same or different. Among them, the resin is, for example, selected from at least one of perfluororesin solutions (D2020), etc.

[0082] Please refer to Figure 12 As described above, in an embodiment of the present invention, when forming a membrane electrode by a transfer assembly, the membrane layer 100 is placed in the middle position to ensure that the membrane layer 100 is flat and without folding. Transfer plates are arranged on both sides of the membrane layer 100, for example, including a first transfer plate 131 and a second transfer plate 132. The first transfer plate 131 and the second transfer plate 132 are of the same size. Openings of the same size and position are respectively arranged at the centers of the first transfer plate 131 and the second transfer plate 132 to determine the transfer area, ensuring that the areas of the catalytic layer regions on both sides of the membrane layer 100 after transfer are the same and the catalytic layer regions are aligned. Air during the transfer process or water vapor generated by heating can be discharged from the edges of the openings. In this application, the size of the openings is not limited and can be set according to the size of the membrane electrode to meet the preparation requirements for forming a larger membrane electrode.

[0083] Please refer to Figure 12As described above, in an embodiment of the present utility model, positioning holes 141 are provided at the diagonal positions of the first transfer plate 131 and the second transfer plate 132, and the positions of the positioning holes 141 on the first transfer plate 131 and the second transfer plate 132 are the same. During transfer, the film layer 100 is placed between the first transfer plate 131 and the second transfer plate 132, and positioning members 14, such as fluorine-containing rubber, are placed in the diagonal positioning holes 141 to fix and position the film layer of the membrane electrode for subsequent transfer processes.

[0084] Please refer to Figure 12 As described above, in an embodiment of the present utility model, the first transfer film 15 is disposed on the side of the first transfer plate 131 away from the film layer 100, and the slurry layer on the first transfer film 15 faces the film layer 100. The second transfer film 16 is disposed on the side of the second transfer plate 132 away from the film layer 100, and the slurry layer on the second transfer film 16 faces the film layer 100. The positioning members 14 define the positions of the first transfer film 15 and the second transfer film 16. At a temperature of, for example, 130 °C to 180 °C, a pressure of, for example, 0.5 MPa to 4 MPa, and a hot pressing time of, for example, 10 s to 600 s, pressure is applied simultaneously on the side of the first transfer film 15 away from the film layer 100 and the side of the second transfer film 16 away from the film layer 100 to transfer the slurry layer on the transfer film to the film layer, and then the transfer film is removed to form an anode catalyst layer and a cathode catalyst layer. By providing the transfer plate and the positioning members, air in the voids in the middle region of the sheet or water vapor generated by heating can be removed during mold closing, avoiding large-area bubble defects in the catalyst region after transfer, improving the quality of the membrane electrode. At the same time, the anode catalyst layer and the cathode catalyst layer are arranged and aligned on both sides of the film layer to ensure the uniformity and stability of catalysis and extend the service life of the electrolytic water device.

[0085] Please refer to Figure 13 and Figure 14 As described above, through the transfer method of the present application, compared with traditional electrode catalyst layers (such as Figure 14 ), an electrode catalyst layer with good surface uniformity (such as Figure 13 ) can be obtained. In some embodiments, the surface roughness Ra of the electrode catalyst layer of the present application can be less than or equal to 0.15 μm, for example, 0.15 to 0.08 μm.

[0086] It should be noted that in the present application, the electrode catalyst layer of the membrane electrode can be formed on the film layer by in-situ growth or transfer method, and the hydrogen consumption layer of the anode catalyst layer can also be formed on the film layer by in-situ growth or transfer method. In one embodiment, a part of the hydrogen consumption layer of the anode catalyst layer can be embedded or fused into the film layer.

[0087] Please refer to Figure 8 and Figure 12As described above, in an embodiment of the present invention, after the transfer is completed, pore formation treatment can be performed on the anode catalyst layer 11 and / or the cathode catalyst layer 12, for example, pore formation treatment can be performed by the cold and hot cycle pore formation method. Specifically, the membrane electrode is immersed in water in a negative pressure environment. After the membrane electrode is fully swollen, the temperature of the membrane electrode is slowly decreased, for example, decreased to -50°C. After keeping the temperature for 12 hours, the temperature is then slowly increased to 70°C, and the cycle is repeated to increase the pore distribution of the catalyst. In this embodiment, the pressure of the negative pressure environment is, for example, 80 KPa, the cooling rate is, for example, 0.5°C / min to 3°C / min, and the heating rate is, for example, 0.5°C / min to 3°C / min. The pore formation treatment method provided by this application is simple, convenient to operate, and after the pore formation treatment, it can increase the pore distribution of the catalyst, increase the porosity of the catalyst, increase the electrolysis rate, and improve the electrolysis efficiency. In an embodiment, the pore size of the pores of the catalyst is, for example, 1 μm to 200 μm.

[0088] The present invention also provides an electrolyzed water device, for example, a proton exchange membrane electrolyzed water hydrogen production device, including the membrane electrode as described above. When the above membrane electrode is applied to a hydrogen production device, it can make hydrogen and oxygen on the anode side react to obtain water, so as to achieve the purpose of hydrogen elimination on the anode side, improve the purity of oxygen on the anode side, and improve the safety of the electrolyzed water device. At the same time, improve the quality of the membrane electrode, ensure the uniformity and stability of catalysis, and extend the service life of the electrolyzed water device. It can increase the electrolysis rate, improve the electrolysis efficiency, and is conducive to promoting the development of the electrolyzed water hydrogen production technology.

[0089] It should be noted that the membrane electrode of this application can be applied to a suitable electrolytic cell, such as a proton exchange membrane (PEM) electrolytic cell, an anion exchange membrane (AEM), an alkaline solution electrolytic cell, a solid oxide (SOEC), or other electrolytic cells.

[0090] In summary, the present invention provides a membrane electrode and a hydrogen production electrolytic cell. Electrode catalyst layers are respectively arranged on the first surface and the second surface of the membrane layer, which can enhance the bonding force between the electrode catalyst layer and the first surface, and the bonding force between the electrode catalyst layer and the second surface, so that the membrane layer and the electrode catalyst layer are tightly combined, and the electrode catalyst layer and the membrane layer are not easily peeled off, thereby improving the stability of the membrane electrode, improving the utilization rate of the catalyst in the electrode catalyst layer, and improving the efficiency of water electrolysis hydrogen production. It can simultaneously improve the purity of hydrogen and oxygen generated by electrolyzing water, and improve the safety of the electrolyzed water device. It can increase the number of micropores of the membrane electrode, provide rich pores for mass transfer, increase the porosity of the catalyst, increase the electrolysis rate, and improve the electrolysis efficiency. It can improve the quality of the membrane electrode. At the same time, the anode catalyst layer and the cathode catalyst layer are arranged and aligned on both sides of the membrane layer to ensure the uniformity and stability of catalysis, and extend the service life of the electrolyzed water device.

[0091] The above embodiments are only illustrative of the principles and effects of the present utility model and are not intended to limit the present utility model. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present utility model. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present utility model should still be covered by the claims of the present utility model.

Claims

1. An electrolytic cell, characterized in that, Comprising: A membrane layer; An anode catalyst layer formed on one side of the membrane layer. The anode catalyst layer includes a hydrogen consumption layer and an anode catalyst base layer. The hydrogen consumption layer is formed between the membrane layer and the anode catalyst base layer, and the hydrogen consumption layer is provided with a bending structure; and A cathode catalyst layer formed on one side of the membrane layer; Bipolar plates located outside the anode catalyst layer and the cathode catalyst layer respectively; Wherein the bending structure of the hydrogen consumption layer is consistent with the flow field distribution of the bipolar plate outside the cathode catalyst layer.

2. The electrolytic cell according to claim 1, characterized in that, The hydrogen consumption layer includes a plurality of arranged strip structures.

3. The electrolytic cell according to claim 2, wherein At one end closer to the water flow direction, the widths of the strip structures of the hydrogen consumption layer increase in sequence.

4. The electrolytic cell according to claim 1, wherein, At one end closer to the water flow direction, the thickness of the hydrogen consumption layer increases.

5. The electrolytic cell according to claim 1, characterized in that, At one end closer to the water flow direction, the density of the hydrogen-consuming catalyst in the hydrogen consumption layer increases in sequence.

6. The electrolytic cell according to claim 1, characterized in that, Part of the hydrogen consumption layer of the anode catalyst layer is embedded or fused into the membrane layer.

7. The electrolytic cell according to claim 1, characterized in that, The thickness ratio of the membrane layer, the anode catalyst layer and the cathode catalyst layer is 1:0.1:0.1 to 1:10:

10.

8. The electrolytic cell according to claim 1, characterized in that, The thickness ratio of the hydrogen consumption layer and the anode catalyst base layer is 1:1 to 1:

10.

9. The electrolytic cell according to claim 1, characterized in that, The porosity of the hydrogen consumption layer is 100 to 330 m 2 / g; and / or, the porosity of the anode catalytic base layer is 100 to 330 m 2 / g; and / or, the porosity of the cathode catalyst layer is 100 to 330 m 2 / g.

10. The electrolytic cell according to claim 1, characterized in that, The electrolytic cell is a proton exchange membrane electrolytic cell, an anion exchange membrane electrolytic cell, an alkaline solution electrolytic cell, or a solid oxide electrolytic cell.

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