A membrane electrode with a hydrogen dissipation layer and its preparation method and application

Abstract

The present invention relates to a membrane electrode with a hydrogen dissipation layer and its preparation and application. The membrane electrode with a hydrogen dissipation layer comprises, in sequence, an anode gas diffusion layer, an anode catalyst layer, a hydrogen dissipation layer, a proton exchange membrane, a cathode catalyst layer and a cathode gas diffusion layer. Photocatalysis and other methods are used to in-situ grow ultra-low loading precious metals, transition metals or alloys on the proton exchange membrane as a hydrogen dissipation layer. At the same time, the precious metal, transition metal or alloy particles in the gas dissipation layer are used as cores to perform in-situ chemical reduction of other precious metals, transition metals or alloys to obtain a catalytic layer, or the catalytic layer is obtained by traditional methods such as spraying and transfer printing. After treatment, it is hot-pressed with the gas diffusion layer to form a membrane electrode with a hydrogen dissipation layer. In the present invention, the hydrogen dissipation layer can consume the hydrogen permeating from the cathode, thereby improving the safety of the water electrolysis process. The membrane electrode constructed thereby has the advantages of ultra-thinness, ultra-low precious metal loading and excellent electrode performance.

Description

Technical Field

[0001] The present invention belongs to the field of electrochemistry (membrane electrode preparation technology), and specifically relates to a membrane electrode with a hydrogen dissipation layer and a preparation method thereof. The prepared membrane electrode can be used in a reaction device for water electrolysis. Background Art

[0002] One strategy to improve the efficiency of hydrogen production from water electrolysis is to reduce the proton transport resistance by using thinner proton exchange membranes. However, a major disadvantage of using membranes is that hydrogen can more easily permeate from the cathode to the oxygen-rich anode, forming an explosive gas, which is particularly dangerous when the cathode side is operated at high pressure. In order to maintain the hydrogen content at a level that meets safety standards, two different strategies can be adopted: (1) reducing hydrogen permeation; (2) reducing the hydrogen content on the anode side.

[0003] The simplest solution to reducing hydrogen permeation is to increase membrane thickness, but this comes at the cost of increased ohmic polarization due to higher membrane resistance. Other solutions include surface or bulk treatment of polymer membranes. In 2008, SAGrigoriev (International Journal of Hydrogen Energy, Volume 34, Issue 14, July 2009, 5986-5991) modified proton exchange membranes using zirconium phosphate or polyetherketone. The results showed that current efficiency could be doubled without significantly affecting the cell voltage. However, such treatments cannot completely solve the gas purity problem, nor can they eliminate the possibility of accumulation and formation of explosive gas mixtures within the electrolyzer.

[0004] To reduce the hydrogen content on the anode side, researchers have studied the effects of factors such as current density (International Journal of Hydrogen Energy, 2017, 42(21): 14355-14366) and gas diffusion layer compression (International Journal of Hydrogen Energy, 2020, 45(7): 4008-4014.) on hydrogen permeation, but there is currently a lack of methods that can effectively reduce the hydrogen content on the anode side. Summary of the Invention

[0005] The present invention addresses the shortcomings of existing technologies by providing a method for preparing and applying a membrane electrode with a hydrogen dissipation layer. The prepared membrane electrode can be used in a water electrolysis device. The hydrogen dissipation layer designed in the present invention can consume hydrogen permeating from the cathode, improving the safety of the water electrolysis process. The resulting membrane electrode with a hydrogen dissipation layer also has the advantages of an ultrathin catalyst layer and excellent electrode performance.

[0006] The technical solution of the present invention is:

[0007] A membrane electrode with a hydrogen dissipation layer comprises an anode gas diffusion layer, a hydrogen dissipation layer, an anode catalyst layer, a proton exchange membrane, a cathode catalyst layer, and a cathode gas diffusion layer; the proton exchange membrane is located between the cathode catalyst layer and the gas dissipation layer, the other side of the hydrogen dissipation layer is the anode catalyst layer, and the outer sides of the anode catalyst layer and the cathode catalyst layer are gas diffusion layers (the outer side of the anode catalyst layer is the anode gas diffusion layer, and the outer side of the cathode catalyst layer is the cathode gas diffusion layer); the metal loading in the hydrogen dissipation layer is 0.001-5 mg / cm -2 , preferably: 0.001-3mg / cm -2 , more preferably 0.01-1 mg / cm -2 The thickness of the hydrogen dissipation layer is 10-3000nm, preferably 20-1000nm; the metal loading in the anode catalyst layer and the cathode catalyst layer is 0.001-3mg / cm 2 , preferably 0.1-1 mg / cm 2 The thickness of the anode catalyst layer and the cathode catalyst layer are both 20-3000nm, preferably 20-1000nm; the thickness of the proton exchange membrane is 5-200μm.

[0008] The anode gas diffusion layer and the cathode gas diffusion layer in the present invention are one or more of foam nickel, foam copper, stainless steel plate, titanium felt, sintered titanium, titanium mesh, titanium plate, carbon felt, carbon paper and carbon cloth.

[0009] The proton exchange membrane of the present invention is a perfluorosulfonic acid proton exchange membrane, which can be a proton exchange membrane represented by Nafion membrane (DuPont, USA), such as Nafion 117, Nafion 115, Nafion 212 or Nafion 211; it can be a DF series proton exchange membrane (Shandong Dongyue Group, China), such as DF988, DF2801; it can also be DF260, NEPEM series ion membrane (Jiangsu Kerun, China), Proton exchange membranes (Gore, USA), BAM membranes (Ballard Energy Systems, Canada), Flemion membranes (Asahi Glass, Japan), and Aciplex series membranes (Asahi Chemical, Japan)

[0010] The metal of the present invention is one or more of platinum, gold, palladium, ruthenium, iridium, rhodium, silver, nickel, cobalt, iron, copper and manganese.

[0011] The hydrogen dissipation layer of the present invention is obtained by photocatalysis, electrochemical deposition, physical vapor deposition, transfer printing or spraying.

[0012] Another object of the present invention is to provide a method for preparing the membrane electrode with a hydrogen dissipation layer, comprising the following steps:

[0013] 1) Preparation of hydrogen dissipation layer:

[0014] Photocatalytic method: The proton exchange membrane loaded with the metal macrocyclic compound is placed in a reaction device, and then the reaction solution is added, followed by illumination with a light source for 1-60 minutes (preferably 1-30 minutes), and then allowed to stand for 1-48 hours (preferably 12-48 hours).

[0015] The light source is one or more of laser, visible light and ultraviolet light;

[0016] 2) Preparation of catalytic layer:

[0017] The reaction solution after use in step (1) is removed and then washed with deionized water. The same or different reaction solution is added to the cathode and anode again, and the reaction is carried out at 30-100° C. for 1-72 hours. Alternatively, a catalytic layer is obtained on both sides of the anode and cathode by conventional methods such as spraying, physical vapor deposition, and transfer printing to obtain a proton exchange membrane with a catalytic layer and a hydrogen dissipation layer;

[0018] In step (1) and step (2), the reaction solution is prepared from a metal salt solution, a surfactant solution, and a reducing agent solution; wherein:

[0019] The concentration of the metal salt solution is 0.1-200 mmol / L, preferably 0.5-100 mmol / L;

[0020] The concentration of the surfactant solution is 0.1-200 mmol / L, preferably 0.1-150 mmol;

[0021] The volume ratio of the surfactant solution to the metal salt solution is 0.1-10:1, preferably 0.5-10:1;

[0022] The concentration of the reducing agent solution is 0.01-20 mol / L, preferably 0.05-10 mmol;

[0023] The volume ratio of the reducing agent solution to the metal salt solution is 1-100:1, preferably 0.5-30:1;

[0024] 3) Preparation of membrane electrode with hydrogen dissipation layer:

[0025] The proton exchange membrane with the catalyst layer obtained in step 2) is dried, and then the anode gas diffusion layer and the cathode gas diffusion layer are placed on both sides of the proton exchange membrane with the catalyst layer and hot pressed for 0.5-10 minutes (preferably 0.5-7 minutes) at 10-150°C (preferably 100-150°C) and 0.1-20MPa (preferably 0.5-15MPa) to obtain a membrane electrode with a hydrogen dissipation layer.

[0026] The metal macrocyclic compound used in the photocatalytic preparation of the hydrogen dissipation layer of the present invention is one or a mixture of two or more of zinc (II) protoporphyrin, 4 (N-methylpyridine) zinc (II) porphyrin, octaethyl zinc (II) porphyrin, tin (IV) porphyrin, 4 (p-sulfonate phenyl) zinc (II) porphyrin, tin (IV) phthalocyanine, zinc (II) protoporphyrin, germanium (IV) porphyrin, 4 (N-methylpyridine) zinc (II) porphyrin, octaethyl zinc (II) porphyrin, tin (IV) porphyrin, 4 (p-sulfonate phenyl) zinc (II) porphyrin, tin (IV) phthalocyanine, germanium (IV) phthalocyanine and magnesium phthalocyanine, or one or a mixture of two or more of phthalocyanine and magnesium phthalocyanine.

[0027] The method for loading the metal macrocyclic compound on the proton exchange membrane in the photocatalytic preparation of the hydrogen dissipation layer of the present invention includes spraying, dipping or printing.

[0028] The reducing agent for photocatalytically preparing the hydrogen dissipation layer of the present invention is at least one of formic acid, acetic acid, formaldehyde, acetaldehyde, ascorbic acid, sodium ascorbate, hydrazine hydrate, ethylene glycol, lithium borohydride, sodium borohydride, potassium borohydride, and glucose.

[0029] The metal salts used in the photocatalytic preparation of the hydrogen dissipation layer of the present invention are copper chloride, copper nitrate, copper sulfate, manganese nitrate, manganese sulfate, manganese chloride, nickel nitrate, nickel sulfate, nickel acetate, nickel chloride, zinc nitrate, zinc chloride, zinc sulfate, zinc acetate, cobalt chloride, cobalt bromide, cobalt iodide, cobalt fluoride, cobalt nitrate, cobalt sulfate, ferric chloride, ferric bromide, ferric iodide, ferric fluoride, ferric nitrate, ferric sulfate, silver nitrate, rhodium trichloride, rhodium sulfate, chlororhodic acid, potassium chlororhodate, sodium chlororhodate, ammonium chlororhodate, ruthenium trichloride, At least one of chlororuthenic acid, potassium chlororuthenate, sodium chlororuthenate, ammonium chlororuthenate, gold trichloride, chloroauric acid, potassium chloroaurate, sodium chloroaurate, ammonium chloroaurate, chloroplatinic acid, chloroplatinous acid, potassium chloroplatinate, potassium chloroplatinite, sodium chloroplatinite, sodium chloroplatinite, ammonium chloroplatinite, ammonium chloroplatinite, iridium trichloride, iridium tetrachloride, chloroiridic acid, potassium chloroiridate, sodium chloroiridate, ammonium chloroiridate, palladium dichloride, potassium chloropalladate, sodium chloropalladate, ammonium chloropalladate, potassium chloropalladate, sodium chloropalladate, ammonium chloropalladate, and palladium sulfate.

[0030] The surfactant used in the photocatalytic preparation of the hydrogen dissipation layer of the present invention is at least one of oleic acid diethanolamide, dodecyl dimethyl betaine, tetradecyl dimethyl sulfoethyl betaine, polyvinyl alcohol, polyacrylic acid, distearoyl phosphatidylcholine, sorbitan laurate, polyethylene glycol octylphenyl ether, polyoxyethylene mono-tert-octylphenyl ether, polyvinyl pyrrolidone, sodium dodecylaminopropionate, lauryl alcohol polyoxyethylene ether, sodium lauryl sulfate, polyoxyethylene lauroyl ether, sodium dodecylbenzene sulfonate, sodium lauryl sulfate, sodium hexadecyl sulfate, polyoxypropylene polyoxyethylene copolymer, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer, hexadecyl trimethylammonium bromide, and octadecyl trimethylammonium chloride.

[0031] The drying conditions for the proton exchange membrane with the catalyst layer grown in step 2) of the present invention are: first drying in air at room temperature, and then drying at 20-120° C. and 0.01-0.5 MPa vacuum.

[0032] Another object of the present invention is to provide an application of the membrane electrode with a hydrogen dissipation layer in water electrolysis.

[0033] The present invention uses methods such as photocatalysis to in-situ grow ultra-low loading precious metals, transition metals or alloys on a proton exchange membrane as a hydrogen dissipation layer, and at the same time uses the precious metal, transition metal or alloy particles in the gas dissipation layer as the core to perform in-situ chemical reduction of other precious metals, transition metals or alloys to obtain a catalytic layer, or obtains the catalytic layer by traditional methods such as spraying and transfer, and after treatment, hot pressing with the gas diffusion layer to form a membrane electrode with a hydrogen dissipation layer. After adding the hydrogen dissipation layer, the hydrogen permeating from the cathode can be consumed, effectively reducing the hydrogen content on the anode side, improving the safety of the water electrolysis process, and providing feasibility for large-scale application of thin films in water electrolysis. At the same time, the constructed membrane electrode with a hydrogen dissipation layer has the advantages of ultra-thinness, ultra-low precious metal loading and excellent electrode performance. The prepared membrane electrode is a reaction device that can be used for water electrolysis.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] 1) The hydrogen dissipation layer of the membrane electrode with a hydrogen dissipation layer prepared by the present invention can effectively reduce the hydrogen content on the anode side, improve the safety of the water electrolysis process, and provide feasibility for the large-scale application of membranes in water electrolysis;

[0036] 2) The membrane electrode with a hydrogen dissipation layer prepared by the present invention has the characteristics of low catalyst precious metal loading and high utilization efficiency, which can greatly reduce the cost of the membrane electrode;

[0037] 3) The membrane electrode preparation method described in the present invention has the characteristics of simple preparation operation, and provides a new technical route for the preparation of water electrolysis membrane electrodes. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention is attached Figure 8 width,

[0039] Figure 1 This is a scanning electron microscope (SEM) photograph of the hydrogen dissipation layer in Example 1;

[0040] Figure 2 This is a SEM photograph of the membrane electrode catalyst layer in Example 2;

[0041] Figure 3 This is a SEM photograph of the membrane electrode catalyst layer in Example 3;

[0042] Figure 4 is the IV curve of the membrane electrode in the water electrolysis cell in Example 3;

[0043] Figure 5 The AC impedance spectrum of the membrane electrode in the water electrolysis cell in Example 3;

[0044] Figure 6 is a Tafel plot of the membrane electrode in the water electrolysis cell in Example 3;

[0045] Figure 7 This is a graph showing the hydrogen content at the anode of the membrane electrode in the water electrolysis cell in Example 4;

[0046] Figure 8 This is a diagram of the anode hydrogen content of the membrane electrode in the water electrolysis cell in Comparative Example 1. DETAILED DESCRIPTION

[0047] The present invention is further described below with reference to the embodiments, but the present invention is not limited thereto.

[0048] Unless otherwise specified, the experimental methods described in the following examples are conventional methods; the reagents and materials described are all commercially available unless otherwise specified.

[0049] Example 1

[0050] The proton exchange membrane Nafion212 (thickness of 125 μm) was soaked in a zinc (II) protoporphyrin solution (0.1 mM), and the soaked proton exchange membrane was loaded into the reaction device. Then, chloroplatinic acid solution (6.67 mM), copper chloride solution (20 mM), polyoxypropylene polyoxyethylene copolymer solution (0.067 mM), and ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1:1 to form a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, and then placed under visible light for 50 minutes and allowed to stand for 24 hours.

[0051] Figure 1This is a SEM photograph of the hydrogen dissipation layer obtained by the photocatalytic method in Example 1. It can be found that Pt has grown on the proton exchange membrane in the form of nanospheres.

[0052] Example 2

[0053] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device. Then, a chloroplatinic acid solution (2 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by illumination under visible light for 50 min and allowed to stand for 24 h.

[0054] b) The reaction solution was poured out and then rinsed with deionized water 8 times. Then, a chloroiridic acid solution (6.67 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.067 mM), and a formic acid solution (1.35 M) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell and reacted at 85°C for 12 hours. The reaction solution was then poured out, rinsed with deionized water, and the proton exchange membrane was removed.

[0055] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform for flat drying at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on both sides of the proton exchange membrane with the catalyst layer grown thereon, and the membrane electrode was prepared by hot pressing at 130°C and 6 MPa for 3 minutes.

[0056] Figure 2 This is a SEM photograph of the membrane electrode catalyst layer with a hydrogen dissipation layer prepared in Example 2. A catalytic layer composed of nanoflower-shaped catalysts was obtained, and the size distribution was uniform. The particle size of the nanoflowers was about 550 nm.

[0057] Example 3

[0058] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a chloroplatinic acid solution (2 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by visible light illumination for 50 min and 24 h.

[0059] b) The reaction solution was poured out and then washed with deionized water 8 times. Then, chloroiridic acid (6.67 mM), polyoxypropylene-polyoxyethylene copolymer (0.0667 mM), and formic acid (1.35 M) were mixed in a volume ratio of 1:1:1 to form a mixed solution as a reaction solution, and the mixed solution (0.8 ml) was added to the anode side of the reaction cell; chloroplatinic acid (2 mM) solution, polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and formic acid solution (1.35 M) were mixed in a volume ratio of 1:1:1 to form a mixed solution as a reaction solution, and the mixed solution (0.8 ml) was added to the cathode side of the reaction cell, and the reaction was carried out at 85°C for 12 h. Then, the reaction solution was poured out, and the proton exchange membrane was removed after rinsing with deionized water.

[0060] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform for flat drying at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on both sides of the proton exchange membrane with the catalyst layer grown thereon, and the membrane electrode was prepared by hot pressing at 130°C and 6 MPa for 3 minutes.

[0061] Figure 3 This is an SEM photograph of the membrane electrode catalyst layer with a hydrogen dissipation layer prepared in Example 3. A catalytic layer composed of nanoflower-shaped catalysts can be obtained, and the size distribution is uniform. The particle size of the nanoflowers is about 300 nm.

[0062] Figure 4 This is the IV curve of the membrane electrode with hydrogen dissipation layer prepared in Example 3 in a water electrolysis cell. The battery test conditions are: H2O flow rate of 20 mL / min, battery temperature of 80°C, atmospheric pressure, and current density of 1 A / cm 2 When the cell voltage is 1.67V.

[0063] Figure 5 The AC impedance spectrum of the membrane electrode with hydrogen dissipation layer prepared in Example 3 in a water electrolysis cell shows that the ohmic impedance of the cell is 59.4 mΩcm 2 , indicating that the contact resistance between parts is greatly reduced.

[0064] Figure 6 The Tafel curve of the membrane electrode with a hydrogen dissipation layer prepared in Example 3 in a water electrolysis cell shows that the membrane electrode has excellent kinetic characteristics.

[0065] Example 4

[0066] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a chloroplatinic acid solution (2 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by visible light illumination for 50 min and 24 h.

[0067] b) The reaction solution was poured out and then rinsed with deionized water 8 times. Then, a chloroiridic acid solution (6.67 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.067 mM), and a formic acid solution (1.35 M) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell and reacted at 85°C for 12 hours. The reaction solution was then poured out, rinsed with deionized water, and the proton exchange membrane was removed.

[0068] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform and dried flat at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on the cathode side of the proton exchange membrane with the catalyst layer grown thereon, and Ti felt was placed on the anode side of the proton exchange membrane with the catalyst layer grown thereon. The membrane was placed in a hot pressing molding machine and hot pressed at 130°C and 6 MPa for 3 minutes to prepare a membrane electrode.

[0069] Figure 7 is the hydrogen content on the anode side of the membrane electrode with a hydrogen dissipation layer prepared in Example 4. At a current density of 33 mA cm -2 The hydrogen content is the highest at 0.22%, which greatly reduces the volume fraction of hydrogen at low current density and improves the safety of using membranes for water electrolysis.

[0070] Example 5

[0071] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a potassium chloroplatinate solution (2 mM), a polyoxypropylene polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by illumination under visible light for 50 min and standing for 24 h.

[0072] b) The reaction solution was poured out and then washed 8 times with deionized water. Then, a mixed solution (0.8 ml) of chloroiridic acid solution (6.67 mM), polyoxypropylene-polyoxyethylene copolymer solution (0.067 mM), and formic acid solution (1.35 M) was mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution was added to both sides of the reaction cell and reacted at 85°C for 12 hours. After that, the reaction solution was poured out, rinsed with deionized water, and the proton exchange membrane was removed.

[0073] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform for flat drying at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on both sides of the proton exchange membrane with the catalyst layer grown thereon, and the membrane electrode was prepared by hot pressing at 130°C and 6 MPa for 3 minutes.

[0074] Example 6

[0075] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a chloroplatinic acid solution (2 mM), a polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer solution (0.0667 mM), and an ascorbic acid solution (50 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by illumination under visible light for 50 min and standing for 24 h.

[0076] b) The reaction solution was poured out and then rinsed with deionized water 8 times. Then, a chloroiridic acid solution (6.67 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.067 mM), and a formic acid solution (1.35 M) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell and reacted at 85°C for 12 hours. After that, the reaction solution was poured out, rinsed with deionized water, and the proton exchange membrane was removed.

[0077] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform for flat drying at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on both sides of the proton exchange membrane with the catalyst layer grown thereon, and the membrane electrode was prepared by hot pressing at 130°C and 6 MPa for 3 minutes.

[0078] Example 7

[0079] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a chloroplatinic acid solution (2 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (150 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by illumination under visible light for 50 min and standing for 24 h.

[0080] b) The reaction solution was poured out and then rinsed with deionized water 8 times. Then, a chloroiridic acid solution (6.67 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.067 mM), and a formic acid solution (1.35 M) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell and reacted at 85°C for 12 hours. The reaction solution was then poured out, rinsed with deionized water, and the proton exchange membrane was removed.

[0081] c) The proton exchange membrane was dried in air at room temperature for 30 minutes and then placed on a vacuum adsorption heating platform for flat drying at 70°C and 0.1 MPa vacuum for 15 minutes. Subsequently, carbon paper was placed on both sides of the proton exchange membrane with the catalyst layer grown thereon, and the membrane electrode was prepared by hot pressing at 130°C and 6 MPa for 3 minutes.

[0082] Example 8

[0083] a) A proton exchange membrane Nafion212 (125 μm thick) was soaked in a zinc (II) protoporphyrin solution (0.1 mM). The soaked proton exchange membrane was placed in a reaction device, and then a chloroplatinic acid solution (2 mM), a polyoxypropylene-polyoxyethylene copolymer solution (0.0667 mM), and an ascorbic acid solution (150 mM) were mixed in a volume ratio of 1:1:1 to prepare a mixed solution as the reaction solution. The mixed solution (0.8 ml) was added to both sides of the reaction cell, followed by illumination under visible light for 50 min and standing for 24 h.

[0084] b) Pt / C and Ir black were sprayed on both sides of the proton exchange membrane with a hydrogen dissipation layer as the cathode catalyst layer and the anode catalyst layer, respectively. The cathode catalyst loading was 0.14 mg Pt cm 2 , the anode catalyst loading is 1 mg Ir cm 2 Then, the carbon paper and Ti felt were used as the cathode gas diffusion layer and the anode gas diffusion layer respectively, and the membrane electrode obtained above were placed in a hot pressing molding machine, and hot pressed at 130°C and 6MPa for 3min to prepare the membrane electrode.

[0085] Comparative Example 1

[0086] Pt / C and Ir black were sprayed on both sides of the proton exchange membrane Nafion212 (thickness 125 μm) as the cathode catalyst layer and the anode catalyst layer, respectively. The cathode catalyst loading was 0.14 mg. Pt cm 2 , the anode catalyst loading is 1 mg Ir cm 2 Then, the carbon paper and Ti felt were used as the cathode gas diffusion layer and the anode gas diffusion layer respectively, and the membrane electrode obtained above were placed in a hot pressing molding machine, and hot pressed at 130°C and 6MPa for 3min to prepare the membrane electrode.

[0087] Figure 8 The hydrogen content on the anode side of the membrane electrode prepared in Comparative Example 1 is 33 mA cm -2 The hydrogen content is the highest at 0.8%, which is 3.63 times the hydrogen content on the anode side of the membrane electrode with a dissipative layer added. The addition of the dissipative layer greatly improves the hydrogen safety of water electrolysis using the membrane.

[0088] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any simple modifications, equivalent variations, and modifications made to the above embodiments based on the technical essence of the present invention that do not depart from the content of the technical solution of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A membrane electrode with a hydrogen dissipation layer, characterized in that: The invention comprises an anode gas diffusion layer, an anode catalyst layer, a hydrogen dissipation layer, a proton exchange membrane, a cathode catalyst layer and a cathode gas diffusion layer in sequence; the metal loading in the hydrogen dissipation layer is 0.001-1 mg / cm 2 The metal loading in the anode catalyst layer and the cathode catalyst layer is 0.001-1 mg / cm 2 The proton exchange membrane is a perfluorosulfonic acid proton exchange membrane with a thickness of 5-200 μm; the anode gas diffusion layer and the cathode gas diffusion layer are one or more of foamed nickel, foamed copper, stainless steel plate, titanium felt, sintered titanium, titanium mesh, titanium plate, carbon felt, carbon paper, and carbon cloth; The metal in the hydrogen dissipation layer is platinum, or platinum and copper, the metal in the anode catalyst layer is one or both of platinum and iridium, and the metal in the cathode catalyst layer is platinum; the thickness of the hydrogen dissipation layer is 10-1000 nm; the thickness of the anode catalyst layer and the cathode catalyst layer are both 20-1000 nm; The method for preparing the membrane electrode with a hydrogen dissipation layer comprises the following steps: 1) Preparation of hydrogen dissipation layer: The proton exchange membrane loaded with the metal macrocyclic compound is placed in the reaction device, and then the reaction solution is added, followed by illumination with a light source for 50-60 minutes, and then allowed to stand for 12-48 hours; The light source is one or more of laser, visible light and ultraviolet light; 2) Preparation of catalytic layer: The reaction solution used in step 1) is removed and then washed with deionized water. The same or different reaction solution is added to the cathode and anode again, and the reaction is carried out at 30-100° C. for 1-12 hours to obtain a catalytic layer on both sides of the cathode and anode, thereby obtaining a proton exchange membrane with a catalytic layer and a hydrogen dissipation layer; 3) Preparation of membrane electrode with hydrogen dissipation layer: The proton exchange membrane with the catalyst layer and the hydrogen dissipation layer obtained in step 2) is dried, and then the anode gas diffusion layer and the cathode gas diffusion layer are placed on both sides of the proton exchange membrane with the catalyst layer and hot pressed at 10-150° C. and 0.1-20 MPa for 0.5-10 minutes to obtain a membrane electrode with a hydrogen dissipation layer; In step 1) and step 2), the reaction solution is prepared by a metal salt solution, a surfactant solution, and a reducing agent solution; wherein: The concentration of the metal salt solution is 0.1-200 mmol / L; The concentration of the surfactant solution is 0.1-200 mmol / L; The volume ratio of the surfactant solution to the metal salt solution is 0.1-10:1; The concentration of the reducing agent solution is 0.01-20 mol / L; The volume ratio of the reducing agent solution to the metal salt solution is 1-100:1; The metal macrocyclic compound is one or a mixture of two or more of zinc (II) protoporphyrin, 4 (N-methylpyridinium) zinc (II) porphyrin, octaethyl zinc (II) porphyrin, tin (IV) porphyrin, 4 (p-sulfonatophenyl) zinc (II) porphyrin, tin (IV) phthalocyanine, germanium (IV) phthalocyanine and magnesium phthalocyanine; The reducing agent is at least one of formic acid, acetic acid, formaldehyde, acetaldehyde, ascorbic acid, sodium ascorbate, hydrazine hydrate, ethylene glycol, lithium borohydride, sodium borohydride, potassium borohydride, and glucose; The surfactant is at least one of oleic acid diethanolamide, dodecyldimethyl betaine, tetradecyldimethyl sulfoethyl betaine, polyvinyl alcohol, polyacrylic acid, distearoyl phosphatidylcholine, sorbitan laurate, polyethylene glycol octylphenyl ether, polyoxyethylene mono-tert-octylphenyl ether, polyvinyl pyrrolidone, sodium dodecylaminopropionate, lauryl alcohol polyoxyethylene ether, sodium lauryl sulfate, polyoxyethylene lauroyl ether, sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium hexadecyl sulfate, polyoxypropylene polyoxyethylene copolymer, polyethylene oxide-polypropylene oxide-polyethylene oxide triblock copolymer, hexadecyltrimethylammonium bromide, and octadecyltrimethylammonium chloride.

2. The membrane electrode with a hydrogen dissipation layer according to claim 1, characterized in that Methods for loading metal macrocyclic compounds onto proton exchange membranes include spraying, dipping, or printing.

3. The membrane electrode with a hydrogen dissipation layer according to claim 1, characterized in that The copper metal salt is at least one of copper chloride, copper nitrate, and copper sulfate; the platinum metal salt is at least one of chloroplatinic acid, chloroplatinous acid, potassium chloroplatinate, potassium chloroplatinite, sodium chloroplatinate, sodium chloroplatinite, ammonium chloroplatinate, and ammonium chloroplatinite; and the iridium metal salt is at least one of iridium trichloride, iridium tetrachloride, chloroiridic acid, potassium chloroiridate, sodium chloroiridate, and ammonium chloroiridate.

4. Use of the membrane electrode with a hydrogen dissipation layer according to claim 1 in water electrolysis.

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