CN107611452A - A kind of preparation method of the membrane electrode containing three-dimensional hydrophobic cathode catalysis layer - Google Patents

Abstract

The invention discloses a method for preparing a membrane electrode containing a three-dimensional hydrophobic cathode catalyst layer. Methods A high-performance, high-power-density membrane electrode with a three-dimensional hydrophobic cathode catalytic layer was prepared by using a catalyst with high platinum content and an ultra-thin proton exchange membrane. In the present invention, the cathode catalytic layer constructs the three-dimensional structure of the catalytic layer by adding carbon nanotubes, etc., so as to improve the porosity of the catalytic layer and the utilization rate of the catalyst, as well as the gas diffusion ability and the transport ability of electrons; and the added hydrophobic substance can effectively improve the performance of the cathode. Water management, especially under high current density, can effectively discharge the water produced by the cathode reaction, ensuring that the cathode reaction gas can smoothly diffuse to the cathode catalytic layer and react with the catalyst. The preparation method of the invention has simple steps, strong feasibility, practicality and easy operation, and low cost; the membrane electrode is small in volume, light in weight, easy to prepare, and can realize large-scale production of the membrane electrode.

Description

A preparation method of a membrane electrode containing a three-dimensional hydrophobic cathode catalyst layer

technical field

The invention relates to the field of proton exchange membrane fuel cells, in particular to a method for preparing a membrane electrode containing a three-dimensional hydrophobic cathode catalyst layer.

Background technique

Proton exchange membrane fuel cell (PEMFC) is a green energy that directly converts chemical energy into electrical energy. It has the advantages of high conversion efficiency, fast start-up at low temperature, and no pollution. It has a wide range of applications in portable electronic devices and power vehicles. prospect. Membrane electrode (MEA) is the core component of a proton exchange membrane fuel cell. It consists of an anode gas diffusion layer, an anode catalyst layer, a proton exchange membrane, a cathode catalyst layer and a cathode gas diffusion layer. The performance of the membrane electrode directly determines the performance of the fuel cell. , the preparation of membrane electrodes with high performance and high power density is of great significance for the commercialization of fuel cells.

Since the reduction of oxygen is much more difficult than the oxidation of hydrogen, plus water is generated and discharged at the cathode, there is simultaneous diffusion of gas and water at the cathode, and the discharge of water. Therefore, the structure and performance of the cathode catalytic layer have a very important impact on the performance of the fuel cell.

The catalytic layer of the membrane electrode is the place where chemical reactions occur, and the utilization rate of the catalyst and the diffusion of the reaction gas in the catalytic layer have a great influence on the performance of the membrane electrode. If the catalyst cannot be fully utilized, the catalyst will be wasted, making it difficult to improve the performance of the membrane electrode. Similarly, the electrons generated during the reaction cannot be conducted in time, and the reaction gas cannot diffuse into the catalytic layer to react with the catalyst in time, which will also limit the progress of the reaction. Improving the utilization rate of the catalyst in the catalytic layer, improving the conductivity of electrons in the catalytic layer and promoting the diffusion of the reaction gas in the catalytic layer are very meaningful research work. In addition, water is generated by the reaction in the cathode catalytic layer of the membrane electrode. If the produced water is not discharged in time, water flooding will occur, resulting in reduced catalyst activity and hindered diffusion of the cathode reaction gas, especially at high current densities. significantly reduced. Membrane electrode cathode water management is also a research hotspot in recent years, in order to improve cathode water management in an effective way, prevent the occurrence of water flooding, and improve the performance of membrane electrodes.

Chinese patent application 200710125266.9 discloses a "fuel cell membrane electrode and its preparation method", the gas diffusion layer in this patent includes a carbon nanotube film structure, the carbon nanotube film structure includes at least one carbon nanotube layer, and the The carbon nanotubes in the carbon nanotube layer are preferentially aligned along the same direction. As a microporous layer, the carbon nanotube film can form a large number of uniform and regularly distributed microporous structures, and has a large specific surface area. This structure can effectively and uniformly diffuse reaction gases and fuels. In addition, the carbon nanotube film has low resistivity and can effectively conduct electrons. But this patent application only involves the addition of carbon nanotubes in the microporous layer (diffusion layer), not the addition of such substances in the catalyst layer.

Chinese patent application 201410358042.2 discloses "fuel cell membrane electrode". The gas diffusion layer used in this patent includes a carbon fiber membrane, and the carbon fiber membrane includes a plurality of carbon nanotubes and a plurality of graphite sheets. The carbon nanotubes are connected end to end and along the Extending in the same direction to form a film, each carbon nanotube is surrounded by a plurality of graphite sheets, and an angle is formed between each graphite sheet and the outer wall of the carbon nanotube. This gas diffusion layer increases the specific surface area of the carbon fiber membrane, improves the ability of the gas diffusion layer to evenly diffuse the reaction gas, and the resistivity of the carbon fiber membrane is small, which improves the ability of the gas to diffuse and conduct electrons, and further improves the performance of the fuel cell membrane. Electrochemical properties such as the reactivity of the electrode. This patent application also only involves the addition of carbon fibers in the gas diffusion layer, not the catalytic layer.

Chinese patent application 201310353990.2 discloses "catalyst for proton exchange membrane fuel cell, its preparation method and proton exchange membrane fuel cell". The catalyst carrier used in this patent is one of activated carbon, carbon nanotube and helical carbon nanotube or more, the prepared catalyst can form a three-dimensional network structure with continuous reactant/product transport channels, proton migration channels and electron conduction channels, which not only improves the electronic conductivity, but also improves the mass transfer effect and reduces the Various polarization losses. The use of catalysts supported by carbon nanotubes to prepare the catalytic layer has the problem of unadjustable hydrophobicity and porosity.

Chinese patent application 99112826.5 discloses "Preparation method of three-in-one assembly of thin-layer hydrophobic catalytic layer electrode and membrane electrode". The patent proposes to add carbon powder treated with hydrophobic substances such as PTFE to the cathode catalytic layer. It is conducive to the formation of gas channels in the electrode catalytic layer and the diffusion of reaction gas or product gas in the catalytic layer. The method proposed in the application can achieve better results, but it is troublesome to prepare PTFE-treated carbon powder, and it is also difficult to control the porosity of the catalytic layer.

Chinese patent application 200810228028.5 discloses "a method for preparing a thin-layer hydrophobic catalytic layer". In this patent, the catalyst and hydrophobic agent are prepared into ink, which is then sprayed on a heat-resistant medium, and subjected to high-temperature roasting to achieve hydrophobicity; roasting Then spray the proton conductor polymer to realize three-dimensional electrode. The membrane electrode prepared by this method has good hydrophobic channels, avoids the flooding phenomenon in the high current density area of the fuel cell, and greatly improves the performance. However, this patent application is only designed to add hydrophobic substances to the catalytic layer, which fails to improve the utilization rate of the catalyst.

Chinese patent application 201610717402.2 discloses "Hydrophilic/Hydrophobic Composite Multilayer Membrane Electrode and Its Preparation Method". The patent invented that the cathode catalytic layer is a three-layer composite structure with a hydrophilic gradient, and the layer close to the proton membrane is a hydrophilic Water-modified layer, the side close to the gas diffusion layer is a hydrophobic modified layer, and the middle of the two layers is an unmodified layer. The hydrophilic layer can moisturize the proton exchange membrane and the ionic polymer in the catalytic layer at low relative humidity , thereby reducing the ion conduction resistance of the membrane electrode, and the hydrophobic layer reduces the capillary pressure gradient between the catalytic layer and the gas diffusion layer, and inhibits the diffusion of water from the diffusion layer to the catalytic layer under high relative humidity. purpose of water distribution. However, the process of preparing a composite multilayer membrane electrode is slightly complicated, which also increases the preparation cost of the membrane electrode.

Although the above reports have recognized the importance of constructing a cathode catalytic layer with good hydrophobicity and made some attempts, there are still many deficiencies in these methods, and the utilization rate of the catalyst in the membrane electrode catalytic layer still needs to be further improved. The conductivity of electrons in the catalytic layer needs to be continuously improved, and there are still some problems in the diffusion of reaction gases in the catalytic layer and the water management of the cathode, so that the membrane electrode of the proton exchange membrane fuel cell cannot achieve high performance under the condition of low platinum loading. . Therefore, the research on the membrane electrode catalytic layer and water management needs to be further improved, especially the research on the membrane electrode cathode catalytic layer.

Contents of the invention

In order to solve the defects and deficiencies in the existing related technologies, the present invention proposes a method for preparing a membrane electrode containing a three-dimensional hydrophobic cathode catalytic layer. The catalytic layer has high catalyst utilization, excellent electron conductivity, and efficient reaction Gas diffusion capacity and product water transport capacity.

The three-dimensional structure aid added in the catalyst layer of the present invention can build the three-dimensional structure of the catalyst layer on the one hand, improve the utilization rate of the catalyst and the diffusion of the reaction gas; on the other hand, because the added three-dimensional structure aid has low resistivity, it can Improve the conductivity of electrons in the catalytic layer; and the hydrophobic substance added to the catalytic layer can effectively improve the water management ability of the cathode catalytic layer, and further enhance the diffusion capacity of the catalytic layer reaction gas. It can be used as the cathode catalytic layer of the membrane electrode, which can greatly improve the performance of the membrane electrode and simplify the manufacturing steps and manufacturing process.

The object of the present invention is achieved at least by one of the following technical solutions.

A method for preparing a membrane electrode containing a three-dimensional hydrophobic cathode catalyst layer, comprising the steps of:

(1) The proton exchange membrane is pretreated successively with deionized water, hydrogen peroxide and sulfuric acid;

(2) Pretreat the three-dimensional structure additive;

(3) Put the carbon-supported platinum catalyst, perfluorosulfonic acid polymer, three-dimensional structure aid, hydrophobic substance and volatile solvent at a mass ratio of 10:2-4:0.1-2:0.1-0.5:500-1500 After mixing, disperse into an ink-like solution after ultrasonic vibration, and then apply the ink-like solution on one side of the proton exchange membrane as the cathode catalyst layer of the membrane electrode, and then put the coated proton exchange membrane at 40-60 ℃ Heat treatment for 20-40 minutes to prepare a three-dimensional hydrophobic cathode catalytic layer; the active component Pt loading in the cathode catalytic layer is 0.1-0.3mgPt·cm ^-2 ;

(4) Mix the carbon-supported platinum catalyst, perfluorosulfonic acid polymer and volatile solvent at a mass ratio of 10:2-4:500-1500, disperse into an ink-like solution after ultrasonic vibration, and apply the solution coated on the other side of the proton exchange membrane treated in step (3), and then heat-treated the coated proton exchange membrane at 40-60°C for 20-40 minutes to prepare the anode catalyst layer of the membrane electrode; The loading of Pt in the anode catalytic layer is controlled at 0.05-0.15mgPt·cm ^-2 ;

(5) Immerse the carbon paper in the polytetrafluoroethylene emulsion for water transfer treatment;

(6) Mix carbon powder, polytetrafluoroethylene emulsion, and volatile solvent at a mass ratio of 10:1-3:500-1500, disperse into an ink-like solution by ultrasonic vibration, and apply the solution to the surface after hydrophobic treatment. One side of the carbon paper, the total amount of carbon material is controlled at 2.0-4.0 mg cm ^-2 , the coated carbon paper is heat-treated at 40-60°C for 20-40 minutes, dried and baked at 300-400°C 1-3 hours, made the cathode gas diffusion layer;

(7) Mix carbon powder, polytetrafluoroethylene emulsion and volatile solvent at a mass ratio of 10:1-3: 500-1500, disperse into an ink-like solution by ultrasonic vibration, and apply the solution to the surface after hydrophobic treatment On one side of the carbon paper, heat-treat the coated carbon paper at 40-60°C for 20-40 minutes, dry it and bake it at 300-400°C for 1-3 hours to prepare the anode gas diffusion layer;

(8) Paste the two gas diffusion layers treated in (6) and (7) respectively on both sides of the proton exchange membrane after the treatment in step (4) to prepare the cathode and anode catalyst layers and the gas diffusion layer the membrane electrode.

In the above method, the proton exchange membrane is a perfluorosulfonic acid resin membrane with a thickness of 20-100 microns.

In the above method, the volatile solvent is more than one of distilled water, ethanol, and isopropanol.

In the above method, the perfluorosulfonic acid polymer includes Nafion212 or Nafion211 proton exchange membrane.

In the above method, the three-dimensional structure aid includes carbon nanotubes, carbon nitride nanotubes, carbon fibers or carbon nitride fibers; the added amount of the three-dimensional structure aid is 1.0%-20.0% of the mass of the cathode catalytic layer.

In the above method, in step (2), the pretreatment of the three-dimensional structure aid includes the following steps:

Put the three-dimensional structure aid in acetone, stir at room temperature for 8-12 hours, filter and then place it in 0.1-2mol L ^-1 sulfuric acid solution, stir for 8-12 hours at 50-70 degrees Celsius to remove possible The metal ions in the poisoned catalyst layer were filtered, washed with deionized water until neutral, and dried.

In the above method, in step (3), while adding a three-dimensional structure aid to the cathode catalyst layer, a hydrophobic substance is added, and the hydrophobic substance includes polytetrafluoroethylene (PTFE) emulsion, polyvinylidene fluoride (PVDF) Emulsion or fluorocarbon resin; the added amount of the hydrophobic substance is 1-5% of the mass of the cathode catalytic layer.

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

1. The three-dimensional structure aids and hydrophobic substances used in the present invention can be directly added to the cathode catalyst slurry and mixed evenly with the catalyst slurry. Adding the three-dimensional structure aids in the cathode catalyst layer can build the three-dimensional structure of the catalyst layer , improve the utilization rate of the catalyst, enhance the conductivity of the electrons and promote the diffusion of the reaction gas; and the addition of hydrophobic substances can effectively improve the water management of the cathode, discharge the water generated by the cathode, and ensure the activity and reaction of the catalyst in the cathode catalytic layer. The gas diffuses smoothly to the catalytic layer, thereby improving the performance of the membrane electrode, especially in the high current density area;

2. The high performance of the membrane electrode prepared by the present invention is reflected in: on the one hand, the addition of the three-dimensional structure aid improves the utilization rate of the catalyst and promotes the diffusion of the reaction gas; Improving the conductivity of electrons in the catalytic layer improves the utilization rate of the catalyst and promotes the diffusion of gas; in the high current density region, the hydrophobic cathode catalytic layer can quickly transfer the generated water to the gas diffusion layer and discharge it. Accelerate the diffusion of the reaction gas into the catalytic layer to participate in the reaction, and achieve the purpose of improving the output performance of the membrane electrode under the synergistic effect of the three-dimensional structure aid and the hydrophobic substance;

3. The method of adding three-dimensional structure aids and hydrophobic substances to the cathode catalytic layer of the present invention is simple and easy to operate, and does not need to go through special and cumbersome operation steps;

4. The single cell assembled by the membrane electrode of the present invention has good performance. Under the condition of working voltage of 0.6-0.7V, the current density is significantly higher than that of the membrane electrode without adding three-dimensional structure aids and hydrophobic substances to the cathode catalytic layer ; In the high current density area, its performance is more obviously better than that of the membrane electrode without adding three-dimensional structure aids and hydrophobic substances in the cathode catalytic layer.

Description of drawings

Figure 1 shows the membrane electrodes prepared in Examples 1 to 3 and the blank membrane electrodes prepared in Comparative Examples in a hydrogen-air battery at a temperature of 70 degrees Celsius, a cathode and anode back pressure of 30 psi, and a relative humidity of 100%. Polarization curve comparison chart;

Figure 2 shows the membrane electrodes prepared in Examples 1 to 3 and the blank membrane electrodes prepared in Comparative Examples in a hydrogen-air battery at a temperature of 70 degrees Celsius, a cathode and anode back pressure of 30 psi, and a relative humidity of 100%. Power Density Comparison Chart.

detailed description

The purpose of the invention of the present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, and the embodiments cannot be repeated here one by one, but the implementation of the present invention is not therefore limited to the following embodiments. Unless otherwise specified, the materials and processing methods used in the present invention are conventional materials and processing methods in the technical field.

Example 1

The first step is to take a 4cm×4cm Nafion211 proton exchange membrane, first place it in deionized water at 80°C for 2 hours, then place it in 5% hydrogen peroxide at 80°C for 2 hours, wash it with distilled water, and wash it at 0.5 mol L ^-1 of sulfuric acid solution at 80 ° C for 2 hours, and then washed with distilled water. Place the treated Nafion membrane on the mold for preparing the membrane electrode and fix it, the size of the active area is 5cm ² , to prevent the membrane from shrinking and deforming during the process of spraying the catalyst slurry;

In the second step, put the carbon nanotubes in acetone, stir at room temperature for 10 hours, filter and then place the carbon nanotubes in a 1mol/L sulfuric acid solution, stir for 10 hours at 60 degrees Celsius, filter and wash with deionized water Carbon nanotubes to neutral, dry;

In the third step, 4.2 mg of Pt/C catalyst (Johnson Matthey) with a Pt content of 60% and 25.2 mg of perfluorosulfonic acid polymer solution (5wt% Nafion, DuPont), 0.42mg of carbon nanotubes, 2.52mg of polytetrafluoroethylene emulsion (5% mass fraction) and 0.42g of isopropanol were mixed and dispersed into a catalyst slurry by ultrasonic vibration, and coated on One side of the proton exchange membrane, and then heat-treated at 50°C for 30 minutes to prepare the cathode catalytic layer, wherein the loading of Pt is 0.2 mg cm ^-1 ;

In the fourth step, 2.1 mg of Pt/C catalyst (Johnson Matthey) with a Pt content of 60%, 12.6 mg of perfluorosulfonic acid polymer solution (5wt% Nafion, DuPont) and 0.21 g of Isopropanol, after mixing, it is dispersed into a catalyst slurry by ultrasonic vibration, and under the irradiation of infrared lamps, it is coated on the other side of the proton exchange membrane that has been sprayed in the fourth step, and then the coated proton exchange membrane is heated at 50°C heat treatment for 30 minutes to prepare the anode catalyst layer of the membrane electrode, wherein the loading of Pt is 0.1 mg cm ^-1 ;

The fifth step is to cut the TGP-H-60 carbon paper into small pieces of 2.5 cm × 2.5 cm, and place it in acetone for 2 hours to remove surface organic impurities. Soak in ethylene emulsion for 15 minutes, dry, so that PTFE accounts for 10% of the weight of the entire carbon paper, and bake at 350°C for 2 hours, so that PTFE is sintered in the carbon paper, that is, the water transfer of the carbon paper is completed deal with;

The sixth step is to weigh 37.5mg XC-72 carbon powder, 150mg polytetrafluoroethylene emulsion (5% mass fraction) and 3.75g isopropanol solution according to the mass ratio of 10:2:1000, mix and disperse by ultrasonic vibration Form an ink-like solution, apply the solution to one side of the hydrophobized carbon paper, bake the coated carbon paper at 50°C for 30 minutes, and bake it at 350°C for 2 hours after drying to obtain gas diffusion layer;

In the seventh step, the two gas diffusion layers sprayed in the sixth step are pasted respectively on both sides of the proton exchange membrane with the cathode and anode catalyst layers sprayed in the third step, so as to obtain the membrane electrode.

The membrane electrode is placed in a single cell. Under the conditions of the cell temperature of 70 degrees and the cathode and anode are fully humidified, the activation treatment is performed for 6 hours, and the battery is fully activated by repeated discharge. The battery performance test conditions are as follows: the fuel gas is hydrogen, the oxidant is Air, the battery temperature is 70°C, the back pressure of the cathode and anode is 30psi, and the relative humidity of the cathode and anode is 100%.

Under the condition that the battery temperature is 70 degrees and the relative humidity of cathode and anode is 100%, the polarization curve of the battery is shown in Figure 1. When the voltage is 0.7V and 0.6V, the current density can reach 1000mAcm ^-2 and 1450 mA cm respectively. ^-2 . The power density curve of a single cell is shown in Figure 2, and the maximum power density is 872mWcm ^-2 .

Example 2

In addition to weighing the Pt/C catalyst with a Pt content of 60%, perfluorosulfonic acid polymer, carbon nanotubes and isopropanol in a mass ratio of 10:3:1:1000 for the cathode catalyst layer slurry (without adding poly Tetrafluoroethylene), other steps are the same as Example 1, and the battery activation method and test method are exactly the same as Example 1. The polarization curve of the battery is shown in Figure 1. When the voltage is 0.7V and 0.6V, the current density can reach 800mAcm ^-2 and 1300mAcm ^-2 respectively. The single cell power density curve is shown in Figure 2, and the maximum power density is 801mWcm ^-2 .

Example 3

In addition to weighing the Pt/C catalyst with a Pt content of 60%, perfluorosulfonic acid polymer, polytetrafluoroethylene emulsion and isopropanol (not Adding carbon nanotubes), other steps are the same as Example 1, and the battery activation method and test method are exactly the same as Example 1. The polarization curve of the battery is shown in Figure 1. When the voltage is 0.7V and 0.6V, the current density can reach 800mAcm ^-2 and 1300mAcm ^-2 respectively. The single cell power density curve is shown in Figure 2, and the maximum power density is 808mWcm ^-2 .

Example 4

In addition to the cathode catalyst layer slurry, weigh the Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate with Pt content of 60% according to the mass ratio of 10:3:0.1:0.3:1000 Except propanol, other steps are identical with example 1.

Example 5

In addition to the cathode catalyst layer slurry, the Pt content is 60% Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate Except propanol, other steps are identical with example 1.

Example 6

In addition to the cathode catalyst layer slurry, the Pt content is 60% Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate Except propanol, other steps are identical with example 1.

Example 7

In addition to the cathode catalyst layer slurry, the Pt content is 60% Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate Except propanol, other steps are identical with example 1.

Example 8

In addition to the cathode catalyst layer slurry, the Pt content is 20% Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate Except propanol, other steps are identical with example 1.

Example 9

In addition to the cathode catalyst layer slurry, the Pt content is 40% Pt/C catalyst, perfluorosulfonic acid polymer, carbon nanotube, polytetrafluoroethylene and isocyanate Except propanol, other steps are identical with example 1.

comparative example

In addition to weighing the Pt/C catalyst with a Pt content of 60%, perfluorosulfonic acid polymer, and isopropanol in a mass ratio of 10:3:1000 for the cathode catalyst layer slurry (without adding carbon nanotubes and polytetrafluoroethylene Vinyl fluoride emulsion), other steps are identical with example 1.

The battery activation method and test method are exactly the same as in Example 1. The battery polarization curve is shown in Figure 1. When the voltage is 0.7V and 0.6V, the current density can reach 700 mA cm ^-2 and 1100 mA cm ^-2 respectively. The single cell power density curve is shown in Figure 2, and the maximum power density is 712mW cm ^-2 .

The above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limiting the implementation of the present invention. For those of ordinary skill in the art, other changes or changes in different forms can be made on the basis of the above description. It is not necessary and impossible to exhaustively list all the implementation manners here. All modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the claims of the present invention.

Claims (7)

1. a kind of preparation method of the membrane electrode containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that comprise the following steps：

（1）PEM is successively pre-processed with deionized water, hydrogen peroxide and sulfuric acid；

（2）Three-dimensional structure auxiliary agent is pre-processed；

（3）Carbon supported platinum catalyst, perfluorinated sulfonic acid polymer, three-dimensional structure auxiliary agent, lyophobic dust and effumability solvent are pressed 10:2-4:0.1-2:0.1-0.5:After 500-1500 mass ratio mixing, black aqueous solution is dispersed into after ultrasonic oscillation, The black aqueous solution is coated in cathode catalysis layer of the PEM side as membrane electrode again, then by coated proton Exchange membrane is heat-treated 20-40 minutes at 40-60 DEG C, that is, the cathode catalysis layer containing three dimensional hydrophobic is made；The negative electrode is urged It is 0.1-0.3mgPtcm to change active component Pt carrying capacity in layer^-2；

（4）Carbon supported platinum catalyst, perfluorinated sulfonic acid polymer and effumability solvent are pressed 10:2-4:500-1500 mass ratio mixes After conjunction, black aqueous solution is dispersed into after ultrasonic oscillation, the solution is coated in through step（3）Proton exchange after processing The opposite side of film, coated PEM is then heat-treated 20-40 minutes at 40-60 DEG C, the sun of membrane electrode is made Pole Catalytic Layer；Pt carrying capacity is controlled in 0.05-0.15mgPtcm in the anode catalyst layer^-2；

（5）Carbon paper is immersed water delivery processing is carried out in ptfe emulsion；

（6）Carbon dust, ptfe emulsion, effumability solvent are pressed 10:1-3:500-1500 mass ratio mixing, ultrasound Ripple concussion is dispersed into black aqueous solution, and the solution is coated to the side of the carbon paper by silicic acid anhydride, the total amount of carbon material Control is in 2.0-4.0 mg cm^-2, coated carbon paper is heat-treated 20-40 minutes at 40-60 DEG C, in 300-400 after drying 1-3 hours are calcined at DEG C, cathode gas diffusion layer is made；

（7）Carbon dust, ptfe emulsion and effumability solvent are pressed 10:1-3:500-1500 mass ratio mixing, ultrasound Ripple concussion is dispersed into black aqueous solution, the solution is coated to the side of the carbon paper by silicic acid anhydride, by coated carbon Paper is heat-treated 20-40 minutes at 40-60 DEG C, is calcined 1-3 hours after drying at 300-400 DEG C, and anodic gas diffusion is made Layer；

（8）Will be through（6）With（7）Two gas diffusion layers after processing are fitted in through step respectively（4）Proton after processing The both sides of exchange membrane, that is, anode and cathode Catalytic Layer, the membrane electrode of gas diffusion layers is made.

2. the method for preparing membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that institute The PEM stated is the perfluorinated sulfonic resin film of the micron thickness of thickness 20-100.

3. the method for preparing membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that institute Effumability solvent is stated as one or more of distilled water, ethanol, isopropanol.

4. the method for preparing membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that institute Stating perfluorinated sulfonic acid polymer includes Nafion212 or Nafion211 PEMs.

5. prepared by the membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that described three Tieing up structural promoter includes CNT, azotized carbon nano pipe, carbon fiber or nitridation carbon fiber；The three-dimensional structure additive dosage For the 1.0%-20.0% of cathode catalysis layer quality.

6. prepared by the membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, step（2）In, it is described to incite somebody to action Three-dimensional structure auxiliary agent carries out pretreatment and comprised the following steps：

Three-dimensional structure auxiliary agent is placed in acetone, 8-12 hours are stirred under normal temperature, are placed on 0.1-2mol L after filtering again^-1's In sulfuric acid solution, 8-12 hours are stirred under conditions of 50-70 degrees Celsius, filters and is washed with deionized to neutrality, drying.

7. the method for preparing membrane electrode according to claim 1 containing three-dimensional hydrophobic cathode catalysis layer, it is characterised in that step Suddenly（3）In, the lyophobic dust includes polytetrafluoroethylene (PTFE)（PTFE）Emulsion, Kynoar（PVDF）Emulsion or fluorine carbon tree Fat；The addition of the lyophobic dust is the 1-5% of cathode catalysis layer quality.