A catalyst layer for fuel cell and a method for preparing the same

Abstract

The present invention discloses a catalytic layer for a fuel cell and a method for preparing the membrane electrode thereof. The catalytic layer comprises an anode catalyst and a cathode catalyst. The anode catalytic layer comprises: a Pt-C catalyst, a high-dielectric small-molecule alcohol, sulfonated lignin-doped conductive polymer nanoparticles, a hydrophilic adhesive, an ionomer solution, and deionized water; the cathode catalytic layer comprises a catalyst, an ionomer solution, a high-dielectric small-molecule alcohol, polytetrafluoroethylene, and deionized water. The method can solve the technical problems of poor water management effect and poor conductivity of the water management materials used in current fuel cell catalytic layers. In the preparation process, the preparation method uses hydrophilic and relatively hydrophobic conductive adhesives to dispense glue on the anode and cathode, respectively, to fix the diffusion layer without losing conductivity. At the same time, the "mouth"-shaped packaging structure performs hydrophilic and hydrophobic management on both sides, effectively improving performance.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel cells, and specifically relates to a catalyst layer for a fuel cell and a method for preparing the membrane electrode thereof. Background Art

[0002] Fuel cells, as efficient and clean energy conversion devices, have garnered extensive attention and research in recent years. Fuel cells directly generate electricity through a chemical reaction between hydrogen and oxygen, offering advantages such as high energy conversion efficiency and minimal environmental pollution. The catalyst layer is a key component in fuel cells, directly impacting their performance and efficiency. Its primary function is to promote the electrochemical reaction between the fuel and oxidant on the electrode surface, thereby increasing the cell's output power and stability.

[0003] Water management in fuel cells is particularly challenging in low humidity or non-humidified conditions. Significant water loss from the proton exchange membrane during operation can cause deformation of the catalyst layer and compromise proton transfer efficiency. Furthermore, most currently used water management materials have poor electrical conductivity, hindering the establishment of the electron transport network in the catalyst layer and, consequently, affecting battery performance. Summary of the Invention

[0004] In order to overcome the defects of the prior art, the present invention provides a catalyst layer for fuel cells and a method for preparing the membrane electrode thereof, which can solve the technical problems of poor water management effect of the catalyst layer for fuel cells and poor conductivity of the water management materials used.

[0005] The object of the present invention is achieved through the following technical solutions:

[0006] In a first aspect, the present invention provides a catalytic layer for a fuel cell, comprising an anode catalyst and a cathode catalyst, wherein the anode catalyst layer comprises: a Pt-C catalyst, a high-dielectric small molecule alcohol, sulfonated lignin-doped conductive polymer nanoparticles, a hydrophilic adhesive, an ionomer solution, and deionized water; the cathode catalyst layer comprises a catalyst, an ionomer solution, a high-dielectric small molecule alcohol, polytetrafluoroethylene, and deionized water.

[0007] The main beneficial effects of the present invention are as follows: hydrophilic substances are added to the anode catalyst slurry of the present invention, which can support efficient water management under high current density even under low humidity conditions or non-humidification conditions; conductive polymer nanoparticles doped with sulfonated lignin are added to the anode catalyst, and sulfonated lignin has good hydrophilicity. Due to its highly branched three-dimensional structure, it can form a stable conductive network with the nano-conductive particles, thereby improving the overall conductivity of the catalytic layer, forming an effect of one plus one being greater than two; and polytetrafluoroethylene has good hydrophobic properties. When the battery is operated at a high current density, a large amount of water will be generated on the cathode side. PTFE can ensure that this water is quickly discharged to avoid the cathode catalyst layer being submerged by water, thereby maintaining a good gas transmission channel. The hydrophilic treatment of the diffusion layer is beneficial to controlling the content of free water inside the battery and avoiding high temperature and power drop caused by water blockage.

[0008] In one embodiment, the high dielectric small molecule alcohol includes at least one of ethanol, ethylene glycol, n-propanol, and isopropanol.

[0009] The main beneficial effects of the present invention are as follows: high-dielectric small molecule alcohol can not only improve the conductivity of the catalytic layer, thereby improving the electrochemical performance of the battery, but also act as a solvent or dispersant to help the catalyst be evenly dispersed in the slurry, thereby improving the uniformity and stability of the catalytic layer.

[0010] In one embodiment, the ionomer solution includes at least one of a sulfonated polyetheretherketone solution, a sulfonated polystyrene solution, a sulfonated polysulfone solution, a sulfonated polyethylene solution, and a perfluorosulfonic acid resin solution.

[0011] In one embodiment, the hydrophilic binder comprises glycerol and / or PEG.

[0012] The hydrophilic binder can not only act as a dispersant to help the catalyst particles disperse evenly in the slurry, thereby improving the uniformity and stability of the catalyst layer, but also improve the water management performance of the catalyst layer, ensuring the water distribution and transport of the proton exchange membrane under low humidity or non-humidification conditions. In one embodiment, in the anode catalyst layer, in the Pt-C catalyst, the Pt loading is 0.03~0.3 mg / cm 2The mass of the effective ingredient in the ionomer solution is 20-80% of the mass of C in the Pt-C catalyst, the mass of the Pt-C catalyst is 5-20% of the mass of the deionized water, the mass ratio of the deionized water to the high dielectric small molecule alcohol is 1:(1-4), the mass of the sulfonated lignin-doped conductive polymer nanoparticles is 0.5-5% of the mass of the Pt-C catalyst, and the mass of the hydrophilic adhesive is 2-5% of the mass of the deionized water; in the cathode catalyst layer, the catalyst is at least one of a Pt-C catalyst and a Ni-Fe catalyst, and the Pt loading in the Pt-C catalyst is 0.3-0.7 mg / cm 2 The mass of the active ingredient in the ionomer solution is 30-80% of the mass of C in the Pt-C catalyst, the mass of the Pt-C catalyst is 5-20% of the mass of the deionized water, the mass ratio of the deionized water to the high dielectric small molecule alcohol is 1:(1-4), and the mass of the polytetrafluoroethylene is 1-5% of the mass of the deionized water.

[0013] By using sulfonated lignin-doped conductive polymer nanoparticles in the above-mentioned mass range, the hydrophilic effect and conductive effect of the sulfonated lignin-doped conductive polymer nanoparticles in the anode catalyst layer can be effectively improved, and the sulfonated lignin-doped conductive polymer nanoparticles can be more stably present in the anode catalyst. If the mass used is not within this range, the conductive properties and hydrophilic properties of the sulfonated lignin-doped conductive polymer nanoparticles will decrease.

[0014] By using polytetrafluoroethylene in the above-mentioned mass range, the hydrophobic effect of polytetrafluoroethylene in the cathode catalyst layer can be effectively improved, and polytetrafluoroethylene can be more stably present in the cathode catalyst. If the mass used is not within this range, the hydrophobic performance of polytetrafluoroethylene will be reduced.

[0015] In a second aspect, the present invention provides a method for preparing a membrane electrode for a fuel cell, comprising the following steps: S1, preparing an anode catalyst layer: mixing the raw materials contained in the anode catalyst layer and preparing it on one side of a proton exchange membrane; preparing a cathode catalyst layer: mixing the raw materials contained in the cathode catalyst layer and preparing it on the other side of the proton exchange membrane; S2, sealing the anode catalyst layer and the cathode catalyst layer with a PEN frame with hot melt adhesive, and the edges of the anode catalyst layer and the cathode catalyst layer are respectively 0.5 to 1 away from the PEN frame. cm; use the initial flat plate hot pressing method to bond the PEN frame; S3, prepare the anode side adhesion layer: apply conductive polymer-sulfonated lignin hydrogel to the edge of the surface of the anode catalyst layer to form an anode side adhesion layer for adhering the anode catalyst layer; prepare the cathode side adhesion layer: apply nafion-PEDOT conductive polymer to the edge of the surface of the cathode catalyst layer to form a cathode side adhesion layer for adhering the cathode diffusion layer; S4, stick the anode diffusion layer to the surface of the anode side adhesion layer, and stick the cathode diffusion layer to the surface of the cathode side adhesion layer; S5, use the secondary flat plate hot pressing method for processing to obtain the membrane electrode for fuel cell; the cathode diffusion layer and the anode diffusion layer respectively include a double-layer composite structure of carbon fiber and graphite and nano-silicon dioxide, and the nano-silicon dioxide is coated on the double-layer composite structure of carbon fiber and graphite.

[0016] This preparation method uses hydrophilic and relatively hydrophobic conductive adhesives to dispense glue on the anode and cathode, respectively, to fix the diffusion layer without losing conductivity. At the same time, the "mouth"-shaped packaging structure is hydrophilic and hydrophobic on both sides, effectively improving performance. Nano-silicon dioxide is attached to the surface of the double-layer composite structure of carbon fiber and graphite by dipping or spraying to form a thin film coating. The raw materials are mixed by at least one of ultrasonic mixing, high-speed shear mixing, ball milling mixing, and high-pressure homogenous mixing. The above mixing method can make the structures of the anode catalyst layer and the cathode catalyst layer more stable and avoid material precipitation.

[0017] In one embodiment, the mass of the nano-silica is 10-40% of the mass of the double-layer composite structure of carbon fiber and graphite, the thickness of the carbon fiber is 150-310 μm, and the thickness of the graphite is 20-40 μm.

[0018] In one embodiment, the total thickness of the PEN frame is 40-80 μm.

[0019] The thickness range of the PEN frame can ensure improved hydrophilicity and water management performance while also avoiding raw material waste, saving materials and reducing costs.

[0020] In one embodiment, the pressure of the first flat plate hot pressing method is less than 0.3 MPa, the temperature is less than 120°C, and the time is 30 s to 1 min; the pressure of the second flat plate hot pressing method is less than 0.3 MPa, the temperature is 130-140°C, and the time is 30 s to 2 min.

[0021] In one embodiment, the thickness of the anode catalyst layer and the cathode catalyst layer are both 5-10 μm.

[0022] This thickness range can ensure that the anode catalyst layer and the cathode catalyst layer have good catalytic efficiency while not causing waste of raw materials.

[0023] The beneficial effects of the present invention are:

[0024] This invention achieves efficient water management by adding a hydrophilic conductive polymer (sulfonated lignin-doped conductive polymer nanoparticles) to the anode catalyst slurry and a hydrophobic material (PTFE) to the cathode catalyst slurry. Specifically, the addition of the hydrophilic conductive polymer absorbs and retains moisture, reducing drying of the proton exchange membrane and ensuring sufficient moisture on the anode side. The addition of the hydrophobic PTFE effectively prevents flooding, ensuring rapid water discharge from the cathode side and maintaining a good gas transmission path.

[0025] Furthermore, by optimizing the catalyst slurry formulation, the present invention increases the conductivity of the catalytic layer, thereby improving the electrochemical performance of the battery. The hydrophilic conductive polymer and nano-conductive particles form a stable conductive network, enhancing the efficiency of electron and proton transport. The addition of a high-dielectric small-molecule alcohol promotes proton conduction and increases the ionic conductivity of the proton exchange membrane, thereby enhancing the overall performance of the battery. By adding a hydrophilic binder (such as glycerol or PEG) to the catalyst slurry, the present invention ensures uniform dispersion of the catalyst particles within the slurry, improving the uniformity and stability of the catalytic layer. The hydrophilic binder reduces the interaction between catalyst particles, prevents particle agglomeration, and ensures uniform distribution of the catalyst within the catalytic layer, thereby ensuring the thickness and uniformity of the catalytic layer and improving its performance.

[0026] In addition, during the preparation process, the present invention uses hydrophilic and relatively hydrophobic conductive adhesives to dispense the anode and cathode respectively, and fixes the diffusion layer without losing conductivity. At the same time, the "mouth"-shaped packaging structure is hydrophilic and hydrophobic on both sides, effectively improving performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Graph showing the temperature change over time of the fuel cells prepared in Examples 1 to 3 and Comparative Examples 1 to 2 in the test examples of the present invention;

[0028] Figure 2 Graph showing the power changes over time of the fuel cells prepared in Examples 1-3 and Comparative Examples 1-2 in the test examples of the present invention. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the accompanying drawings. Example

[0030] This embodiment provides a catalyst layer for a fuel cell and a method for preparing the membrane electrode thereof:

[0031] The ingredients are as follows:

[0032] Cationic catalyst layer: deionized water 100 g, ethanol 100 g, Pt-C catalyst 15 g (Pt loading is 0.03 mg / cm 2 ), 0.075 g of sulfonated lignin-doped conductive polymer nanoparticles, 2 g of glycerol, and 40 g of sulfonated polyetheretherketone solution (containing 10 wt% of sulfonated polyetheretherketone);

[0033] Cathode catalyst: deionized water 100 g, ethylene glycol 100 g, Pt-C catalyst 15 g (Pt loading is 0.3 mg / cm 2 ), 1 g of polytetrafluoroethylene, and 31.5 g of sulfonated polystyrene solution (containing 10 wt% of sulfonated polystyrene).

[0034] Here are the steps:

[0035] S1. Mixing the slurries of the anode catalyst layer and the cathode catalyst layer separately by ultrasonic mixing;

[0036] S2. Apply the dispersed anode catalyst slurry to one side of the proton exchange membrane by screen printing; prepare a membrane layer with a dry film thickness of 5 μm;

[0037] S3, applying the dispersed cathode catalyst slurry to the other side of the proton exchange membrane by screen printing; preparing a membrane layer with a dry film thickness of 5 μm;

[0038] S4. Use ultrasound (40 Hz, 10°C, 10 min) to disperse 20 nm silica and acetylacetone in isopropanol. The mass ratio of silica, acetylacetone, and isopropanol is 2%:5%:93%. Then, add concentrated sulfuric acid dropwise until the pH is less than 1. Continue ultrasound (40 Hz, 5°C) for 30 min.

[0039] S5. Immerse the anode / cathode diffusion layer (a double-layer composite structure of carbon fiber and graphite, with a carbon fiber thickness of 150 μm and a graphite thickness of 20 μm) in a silica suspension for 10 seconds, then dry at 140°C for 10 minutes. Repeat the immersion process 4 to 5 times until the silica content in the diffusion layer reaches 10%.

[0040] S6. Seal the anode catalyst layer and the cathode catalyst layer with a PEN frame with hot melt adhesive, with the edges of the anode catalyst layer and the cathode catalyst layer each 0.5 cm away from the PEN frame; bond the PEN frame using a primary flat plate hot pressing method (pressure 0.2 MPa, temperature 100° C., time 0.5 min);

[0041] S7. Attaching the anode diffusion layer: applying a conductive polymer-sulfonated lignin hydrogel to the edge of the anode catalyst layer to form an anode diffusion layer, and the anode diffusion layer adheres to the edge of the anode catalyst layer; attaching the cathode diffusion layer: applying a nafion-PEDOT conductive polymer to the edge of the cathode catalyst layer to form a cathode diffusion layer, and the cathode diffusion layer adheres to the edge of the cathode catalyst layer;

[0042] S8. The catalyst layer for the fuel cell is obtained by performing a secondary flat plate hot pressing method (pressure of 0.2 MPa, temperature of 130° C., and time of 0.5 min). Example

[0043] This embodiment provides a catalyst layer for a fuel cell and a method for preparing the membrane electrode thereof:

[0044] The ingredients are as follows:

[0045] Cationic catalyst layer: deionized water 100 g, ethanol 400 g, Pt-C catalyst 20 g (Pt loading is 0.3 mg / cm 2 ), sulfonated lignin-doped conductive polymer nanoparticles 1 g, PEG 5 g, sulfonated polysulfone solution 56 g (containing 20 wt% sulfonated polysulfone);

[0046] Cathode catalyst: deionized water 100 g, ethylene glycol 400 g, Pt-C catalyst 20 g (Pt loading is 0.7 mg / cm 2 ), 5 g of polytetrafluoroethylene, and 48 g of sulfonated polyethylene solution (containing 10 wt% of sulfonated polyethylene).

[0047] Here are the steps:

[0048] S1. Mixing the slurries of the anode catalyst layer and the cathode catalyst layer separately by high-speed shear mixing;

[0049] S2. The dispersed anode catalyst slurry is sprayed on one side of the proton exchange membrane; the dry film thickness of the prepared membrane is 10 μm;

[0050] S3. Apply the dispersed cathode catalyst slurry to the other side of the proton exchange membrane using one of the following methods: wire rod coating, blade coating, or slit coating; prepare a membrane layer with a dry film thickness of 10 μm;

[0051] S4. Use ultrasound (40 Hz, 10°C, 10 min) to disperse 20 nm silica and acetylacetone in isopropanol. The mass ratio of silica, acetylacetone, and isopropanol is 2%:5%:93%. Then, add concentrated sulfuric acid dropwise until the pH is less than 1. Continue ultrasound (40 Hz, 5°C) for 30 min.

[0052] S5. Immerse the anode / cathode diffusion layer (a double-layer composite structure of carbon fiber and graphite, with a carbon fiber thickness of 310 μm and a graphite thickness of 40 μm) in a silica suspension for 10 seconds, then dry at 140°C for 10 minutes. Repeat the immersion process 4 to 5 times until the silica content in the diffusion layer reaches 40%.

[0053] S6. Seal the anode catalyst layer and the cathode catalyst layer with a PEN frame with hot melt adhesive, with the edges of the anode catalyst layer and the cathode catalyst layer respectively 1 cm away from the PEN frame; bond the PEN frame using a primary flat plate hot pressing method (pressure 0.28 MPa, temperature 118° C., time 1 min);

[0054] S7, pasting the anode side diffusion layer: applying the conductive polymer-sulfonated lignin hydrogel to the edge of the surface of the anode catalyst layer by dispensing, and pasting the anode side diffusion layer; pasting the cathode side diffusion layer: applying the nafion-PEDOT conductive polymer to the edge of the surface of the cathode catalyst layer by dispensing, and pasting the cathode side diffusion layer;

[0055] S8. The catalyst layer for the fuel cell is obtained by performing a secondary flat plate hot pressing method (pressure of 0.28 MPa, temperature of 140° C., and time of 2 min). Example

[0056] This embodiment provides a catalyst layer for a fuel cell and a method for preparing the membrane electrode thereof:

[0057] The ingredients are as follows:

[0058] Cationic catalyst layer: deionized water 100 g, ethanol 200 g, Pt-C catalyst 18 g (Pt loading is 0.2 mg / cm 2), 0.36 g of sulfonated lignin-doped conductive polymer nanoparticles, 4 g of a mixture of PEG and glycerol, and 43.2 g of a mixed solution of sulfonated polysulfone and sulfonated polystyrene (containing 10 wt% of sulfonated polysulfone and 10 wt% of sulfonated polystyrene);

[0059] Cathode catalyst: deionized water 100 g, ethylene glycol 300 g, Pt-C catalyst 16 g (Pt loading is 0.5 mg / cm 2 ), 4 g of polytetrafluoroethylene, and 28 g of a mixed solution of sulfonated polyethylene and sulfonated polyetheretherketone (containing 10 wt% of sulfonated polyethylene and 10 wt% of sulfonated polyetheretherketone).

[0060] Here are the steps:

[0061] S1, mixing the slurries of the anode catalyst layer and the cathode catalyst layer respectively by ball milling;

[0062] S2. Apply the dispersed anode catalyst slurry to one side of the proton exchange membrane by transfer printing; the prepared membrane layer has a dry film thickness of 8 μm;

[0063] S3, applying the dispersed cathode catalyst slurry to the other side of the proton exchange membrane by a transfer printing method; the prepared membrane layer has a dry film thickness of 8 μm;

[0064] S4. Use ultrasound (40 Hz, 10°C, 10 min) to disperse 20 nm silica and acetylacetone in isopropanol. The mass ratio of silica, acetylacetone, and isopropanol is 2%:5%:93%. Then, add concentrated sulfuric acid dropwise until the pH is less than 1. Continue ultrasound (40 Hz, 5°C) for 30 min.

[0065] S5. Immerse the anode / cathode diffusion layer (a double-layer composite structure of carbon fiber and graphite, with a carbon fiber thickness of 220 μm and a graphite thickness of 30 μm) in a silica suspension for 10 seconds, then dry at 140°C for 10 minutes. Repeat the immersion process 4 to 5 times until the silica content in the diffusion layer reaches 30%.

[0066] S6. Seal the anode catalyst layer and the cathode catalyst layer with a PEN frame with hot melt adhesive, with the edges of the anode catalyst layer and the cathode catalyst layer respectively 1 cm away from the PEN frame; bond the PEN frame using a primary flat plate hot pressing method (pressure 0.25 MPa, temperature 110° C., time 1.5 min);

[0067] S7, pasting the anode side diffusion layer: applying a conductive polymer-sulfonated lignin hydrogel to the edge of the surface of the anode catalyst layer to form an anode side adhesion layer, and the anode side diffusion layer adheres to the edge of the anode catalyst layer; pasting the cathode side diffusion layer: applying a nafion-PEDOT conductive polymer to the edge of the surface of the cathode catalyst layer to form a cathode side adhesion layer, and the cathode side diffusion layer adheres to the edge of the cathode catalyst layer;

[0068] S8. A secondary flat plate hot pressing method (pressure of 0.25 MPa, temperature of 135° C., and time of 1.5 min) is used to obtain the catalyst layer for the fuel cell.

[0069] Comparative Example 1

[0070] The sulfonated lignin doping was removed and only conductive polymer nanoparticles were used, with the rest being the same as in Example 2.

[0071] Comparative Example 2

[0072] Except for removing the polytetrafluoroethylene, the rest is the same as in Example 2.

[0073] Test example

[0074] The catalytic layers of Examples 1-3 and Comparative Examples 1-2 were cut into 5 cm × 5 cm single pieces, sealed by hot melt sealing, and matched with 180 μm diffusion layers to prepare 30 membrane electrode sheets, which were stacked and activated and tested for performance.

[0075] Activation conditions: hydrogen 0.1 MPa, air 0.1 MPa, flow rate of 700 mL / min, 2800 mL / min, 60% humidification, 50°C, 4 A, constant current discharge every 2 A for 30 min, 10 A, constant current discharge every 5 A for 30 min, 19 A, constant current discharge every 2 A for 30 min).

[0076] Constant current discharge conditions: hydrogen at 0.1 MPa, air at 0.1 MPa, flow rates of 700 mL / min and 2800 mL / min, 60% humidification, 50°C, and a constant current of 15 A for 110 h. Stack power and temperature were continuously recorded.

[0077] according to Figure 1 The results show that the temperature of the fuel cells prepared using the technical solutions of Examples 1 to 3 is significantly lower than that of the fuel cells prepared in Comparative Examples 1 to 2. This shows that the fuel cell catalyst layer and membrane electrode prepared by the present invention have a good effect in reducing the temperature of the fuel cell. Figure 2The results show that the power of the fuel cells prepared using the technical solutions of Examples 1 to 3 is significantly higher than that of the fuel cells prepared in Comparative Examples 1 to 2. This shows that the fuel cell catalyst layer and membrane electrode prepared by the present invention have a good effect in increasing the temperature power of the fuel cell.

[0078] In the description of the present invention, it should be understood that the terms "upper", "lower", "bottom", "top", "front", "back", "inside", "outside", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention.

[0079] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the invention. It should be understood that many modifications may be made to the illustrative embodiments, and that other arrangements may be devised, without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in ways other than those described in the original claims. It should also be understood that features described in conjunction with individual embodiments may be employed in conjunction with other described embodiments.

Claims

1. A membrane electrode with a catalyst layer for a fuel cell, characterized in that: The catalytic layer includes an anode catalyst and a cathode catalyst, wherein the anode catalyst layer includes: a Pt-C catalyst, a high-dielectric small molecule alcohol, sulfonated lignin-doped conductive polymer nanoparticles, a hydrophilic adhesive, an ionomer solution, and deionized water; The cathode catalyst layer includes a catalyst, an ionomer solution, a high dielectric small molecule alcohol, polytetrafluoroethylene, and deionized water; In the anode catalyst layer, the Pt loading in the Pt-C catalyst is 0.03-0.3 mg / cm 2 The mass of the active ingredient in the ionomer solution is 20-80% of the mass of C in the Pt-C catalyst, the mass of the Pt-C catalyst is 5-20% of the mass of the deionized water, the mass ratio of the deionized water to the high dielectric small molecule alcohol is 1:(1-4), the mass of the sulfonated lignin-doped conductive polymer nanoparticles is 0.5-5% of the mass of the Pt-C catalyst, and the mass of the hydrophilic adhesive is 2-5% of the mass of the deionized water; In the cathode catalyst layer, the catalyst in the cathode catalyst layer is at least one of a Pt-C catalyst and a Ni-Fe catalyst, and in the Pt-C catalyst, the Pt loading amount is 0.3-0.7 mg / cm 2 The mass of the active ingredient in the ionomer solution is 30-80% of the mass of C in the Pt-C catalyst, the mass of the Pt-C catalyst is 5-20% of the mass of the deionized water, the mass ratio of the deionized water to the high dielectric small molecule alcohol is 1:(1-4), and the mass of the polytetrafluoroethylene is 1-5% of the mass of the deionized water; In the preparation method of the membrane electrode of the catalyst layer for fuel cells, the anode side adhesion layer is prepared by dispensing a conductive polymer-sulfonated lignin hydrogel on the edge of the surface of the anode catalyst layer to form an anode side adhesion layer for adhering the anode catalyst layer; the cathode side adhesion layer is prepared by dispensing an ionomer solution on the edge of the surface of the cathode catalyst layer to form a cathode side adhesion layer for adhering the cathode diffusion layer, wherein the ionomer solution is a nafion-PEDOT conductive polymer; the membrane electrode of the catalyst layer for fuel cells is packaged in a square shape; The high dielectric small molecule alcohol includes at least one of ethanol, ethylene glycol, n-propanol, and isopropanol; The ionomer solution comprises at least one of a sulfonated polyetheretherketone solution, a sulfonated polystyrene solution, a sulfonated polysulfone solution, a sulfonated polyethylene solution, and a perfluorosulfonic acid resin solution; The hydrophilic binder includes glycerol and / or PEG.

2. A method for preparing a membrane electrode with a catalyst layer for a fuel cell according to claim 1, characterized in that: The steps include: S1. Preparing an anode catalyst layer: mixing the raw materials of the anode catalyst layer and preparing the mixture on one side of a proton exchange membrane; Preparation of a cathode catalyst layer: Mixing the raw materials for the cathode catalyst layer and preparing the mixture on the other side of the proton exchange membrane; S2. Seal the anode catalyst layer and the cathode catalyst layer with a PEN frame with hot melt adhesive, with the edges of the anode catalyst layer and the cathode catalyst layer respectively being 0.5 to 1 cm away from the PEN frame; and bond the PEN frame using a primary flat plate hot pressing method; S3, preparing an anode side adhesion layer: applying a conductive polymer-sulfonated lignin hydrogel to the edge of the surface of the anode catalyst layer to form an anode side adhesion layer for adhering the anode catalyst layer; Preparation of cathode side adhesion layer: dispensing nafion-PEDOT conductive polymer on the edge of the cathode catalyst layer to form a cathode side adhesion layer for adhering to the cathode diffusion layer; S4, pasting the anode diffusion layer on the surface of the anode side adhesion layer, and pasting the cathode diffusion layer on the surface of the cathode side adhesion layer; S5, performing treatment by a secondary flat plate hot pressing method to obtain a membrane electrode having a catalyst layer for a fuel cell; The cathode diffusion layer and the anode diffusion layer respectively include a double-layer composite structure of carbon fiber and graphite and nano-silicon dioxide, and the nano-silicon dioxide is coated on the double-layer composite structure of carbon fiber and graphite.

3. The method for preparing a membrane electrode having a catalyst layer for a fuel cell according to claim 2, wherein: The mass of the nano-silicon dioxide is 10-40% of the mass of the double-layer composite structure of carbon fiber and graphite. The thickness of the carbon fiber is 150-310 μm, and the thickness of the graphite is 20-40 μm.

4. The method for preparing a membrane electrode having a catalyst layer for a fuel cell according to claim 2, wherein: The total thickness of the PEN frame is 40-80 μm.

5. The method for preparing a membrane electrode having a catalyst layer for a fuel cell according to claim 2, wherein: The pressure of the primary flat-plate hot pressing method is less than 0.3 MPa, the temperature is less than 120°C, and the time is 30 s to 1 min; the pressure of the secondary flat-plate hot pressing method is less than 0.3 MPa, the temperature is 130-140°C, and the time is 30 s to 2 min.

6. The method for preparing a membrane electrode having a catalyst layer for a fuel cell according to claim 2, wherein: The thickness of the anode catalyst layer and the cathode catalyst layer are both 5-10 μm.

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