Integrated membrane electrode for water electrolysis and fuel cell, and preparation method

Abstract

An integrated membrane electrode for water electrolysis and a fuel cell, and a preparation method. The integrated membrane electrode comprises an enhanced proton exchange membrane, and a catalytic layer having high proton transmission efficiency. In a preparation process, a support body is subjected to compatibility modification treatment, then a coating process is used on two sides to prepare a proton exchange membrane compact layer and a catalytic layer, to implement integrated preparation of a membrane electrode CCM. A large quantity of nano-scale water-retaining functional particles are uniformly distributed in a reinforcing body and the catalytic layer of the prepared integrated membrane electrode, and the proton exchange membrane uses a short side chain resin. The configuration of the described structure can facilitate improvement of the mechanical strength of membrane electrode CCM, reduce thickness of the CCM, improve the electrical conductivity thereof, and simultaneously be compatible with membrane electrode performance requirements for water electrolysis and fuel cells in high and low temperatures and different humidity environments, thereby simplifying the preparation process.

Description

Integrated membrane electrode for water electrolysis and fuel cell and preparation method thereof Technical Field

[0001] The present invention relates to an integrated membrane electrode for water electrolysis and fuel cells and a preparation method thereof, belonging to the field of fuel cells and water electrolysis membrane electrode materials. Background Art

[0002] Energy shortages are becoming increasingly severe worldwide. Traditional fossil fuels are non-renewable and cause significant environmental pollution during their use. However, the vast majority of energy conversion occurs through thermal processes, which have low conversion efficiency. Growing global energy consumption and the demand for energy conservation and emission reduction are the primary drivers for the development of renewable energy. Hydrogen, with its advantages of zero emissions and high energy density, is considered an ideal energy carrier for the future energy society. Hydrogen produced by water electrolysis not only balances loads and shifts peak loads in smart grids, but also allows for widespread use in transportation, methane synthesis, and natural gas supply networks. In recent years, fuel cells have made significant progress and have been practically applied in various fields. Fuel cells are not limited by the Carnot cycle and have high theoretical energy conversion rates. They use hydrogen-rich fuels such as hydrogen, methanol, and hydrocarbons, making them environmentally friendly. Therefore, fuel cells (PEMFCs) hold broad application prospects. The membrane electrode (MEE) is a key component of fuel cells. The main process involves coating a catalyst slurry onto a proton exchange membrane (PEM), drying it to form a CCM, and then encapsulating it to form the membrane electrode. Proton exchange membrane water electrolysis (PEMWE) technology has been widely studied and is being applied in large-scale membrane demonstrations due to its advantages such as high current density, small footprint, fast dynamic response, wide operating range, high hydrogen production purity (purity can reach 99.99%), and high-pressure operation.

[0003] At present, whether it is fuel cells or PEM water electrolysis, increasing the operating temperature is beneficial to improving the performance of membrane electrodes. However, the imported perfluorosulfonic acid membranes and imported perfluorosulfonic acid resins currently used are not only expensive and technologically monopolized, but also because perfluorosulfonic acid resins are heavily dependent on the presence of water during proton transfer, the conductivity and proton transfer efficiency of the membrane electrode are significantly reduced in low-humidity environments. Therefore, the current public technology for membrane electrodes is usually to prepare the proton exchange membrane and the membrane electrode CCM independently, and there are few integrated membrane electrode preparation processes. There are few membrane electrode preparation methods suitable for PEM water electrolysis and fuel cells with a wide temperature range (60-150°C) and a wide humidity range (RH10-100%).

[0004] In addition, in the existing CCM preparation process, its surface uniformity has always been one of the key research and development technologies in this field. At the same time, for the CCM anode and cathode, in this field, most of the anode and cathode are distinguished by the high and low loadings, that is, the high loading is the cathode side, and the low loading is the anode side. However, in the CCM preparation process, it is difficult to control the high and low loadings. Since the slurry loadings on both sides of the CCM are required to be different, the slurry needs to be strictly controlled in terms of parameters such as discharge amount, coating speed, and coating times when discharging. Mechanical equipment is not sensitive to slight adjustments, so it is often necessary to conduct numerous experimental adjustments to obtain a suitable preparation process, thereby obtaining a CCM with uniform surface. On the other hand, during the CCM preparation process, the catalyst slurry itself has a certain fluidity. After it is coated on the proton exchange membrane, microscopic flow will occur during the continuous transmission of the membrane, which will affect the uniformity of the coating surface. In order to reduce the flow of the slurry, the concentration of the slurry can be increased when preparing the catalyst slurry. However, the slurry with a higher concentration has poor fluidity and high surface tension, so there are still many particles after the slurry is stirred. Combined with the problem of weak adhesion of the slurry to the proton exchange membrane surface, the final CCM surface will have uniformity problems such as particles, pinholes, and defects, which directly affect the CCM qualification rate.

[0005] Summary of the Invention

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide an integrated membrane electrode for water electrolysis and fuel cells and a preparation method. The integrated membrane electrode includes a reinforced proton exchange membrane and a catalytic layer with high proton transfer efficiency. During the preparation process, the support body is first modified for compatibility, and then a proton exchange membrane dense layer and a catalytic layer are prepared on both sides by a coating process to realize the integrated preparation of the membrane electrode CCM; in the integrated membrane electrode prepared by the present invention, a large number of nano-water-retaining functional particles are evenly distributed in the reinforcement and the catalytic layer, and the proton exchange membrane uses a short side chain resin. The construction of the above structure can help to improve the mechanical strength of the membrane electrode CCM, reduce the thinning of the CCM, improve the conductivity, and simultaneously be compatible with the membrane electrode performance requirements of water electrolysis and fuel cells in high and low temperature and different humidity environments, thereby simplifying the preparation process.

[0007] In order to achieve the above-mentioned object of the invention, the present invention adopts the following technical solutions:

[0008] The present invention provides a method for preparing an integrated membrane electrode for water electrolysis and fuel cells, comprising the following steps:

[0009] Step 1: Preparation of a pre-treatment reinforcement layer: Water-retaining nanoparticles and perfluorosulfonic acid resin dispersed in an alcohol-water solution are sprayed onto the porous PTFE membrane and dried to form a pre-treatment reinforcement layer;

[0010] Step 2: Apply the casting slurry on one side of the PE / PET protective film and dry it at 60-90°C for 10-60 seconds to form a partially dried wet film layer I. The thickness of the wet film layer I is controlled at 40-150 μm.

[0011] Step 3: Laying one side of the pretreated reinforcement layer obtained in step 1 on the wet film layer I, then coating the other side of the pretreated reinforcement layer with a casting slurry, and drying at 60-90°C for 10-200 seconds to form a partially dried wet film layer II, repeating this step 1-10 times, with the thickness of each wet film layer II controlled to be 100-500 μm, to obtain a proton exchange reinforced membrane; in steps 2 and 3, the casting slurry is: an alcohol aqueous solution containing nano water-retaining particles and a perfluorosulfonic acid resin;

[0012] Step 4: Apply slurry 1 on the wet film layer II in step 3 and dry it. The slurry 1 includes water-retaining nanoparticles and a catalyst. The catalyst loading is 0.2-3 mg / cm 2 ;

[0013] Step 5: Peel off the film from the PE / PET protective film after step 4, apply slurry 2 on the wet film layer I, and dry it to obtain CCM. The slurry 2 includes water-retaining nanoparticles and catalyst, and the catalyst loading is 0.2-1 mg / cm 2 ;

[0014] Step 6: Hot pressing and packaging to form an integrated membrane electrode for water electrolysis and fuel cells.

[0015] Furthermore, in the above technical solution,

[0016] In step 1: Preparation of pre-treatment reinforcement layer: the thickness of porous PTFE membrane is 1-10 μm, the porosity is 40-85%; the mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:1-5, and the spraying load is 1-10 mg / cm 2 ; After drying at 40-60℃, a pre-treated reinforcement layer is formed;

[0017] In step 2: the PE / PET protective film is laid flat on a vacuum adsorption coating platform at 40-80°C; the casting slurry coating speed is 0.1-5 cm / s;

[0018] In step 3: the coating speed is 0.1-5 cm / s;

[0019] In step 4, the catalyst in slurry 1 is a Pt-based or iridium-based catalyst, the mass ratio of water-retaining agent nanoparticles to catalyst is 1:5-20, and the dispersing agent is an alcohol-water solution; the coating speed is 0.5-5 mm / s, the coating temperature is 40-90° C., and the concentration of the alcohol-water solution is 1-20 g / L;

[0020] In step 5: the catalyst in slurry 2 is a Pt-based noble metal catalyst or a non-noble metal catalyst, the mass ratio of water-retaining agent nanoparticles to catalyst is 1:5-20, the dispersing agent is an alcohol-water solution; the coating speed is 0.5-5 mm / s, the coating temperature is 40-90°C, and the concentration of the alcohol-water solution is 1-20 g / L;

[0021] In step 6: the CCM obtained in step 5 is packaged with the gas diffusion layer and the polyester frame by hot pressing to form a membrane electrode; the hot pressing temperature is 70-150°C.

[0022] Furthermore, in the above technical solution, in steps 1-6, the nano water-retaining particles are one or more of TiO2, ZSM5, and ZSM35 molecular sieves, and the particle size of the nanoparticles is 1-20 nm.

[0023] Furthermore, in the above technical solution, in steps 2 and 3, the mass ratio of the nano water-retaining particles to the perfluorosulfonic acid resin in the casting slurry is 1:10-200, and the concentration of the perfluorosulfonic acid resin is 2-10 wt.%.

[0024] Furthermore, in the above technical solution, the alcohol in the alcohol aqueous solution is independently selected from a mixture of one or more of ethanol, n-propanol, isopropanol, methanol, and n-butanol.

[0025] Furthermore, in the above technical solution, the perfluorosulfonic acid resin is a long side chain resin or a short side chain perfluorosulfonic acid resin, wherein the short side chain molecular structure is One or more of .

[0026] The present invention provides an integrated membrane electrode for water electrolysis and fuel cells obtained by the above preparation method.

[0027] The present invention provides the use of the integrated membrane electrode as a membrane electrode in a water electrolysis cell and a fuel cell.

[0028] Furthermore, in the above technical solution, the fuel cell used is a high-temperature proton exchange membrane fuel cell with an anhydrous system, a low-humidity air intake environment, and an operating temperature of 100-150°C; the water electrolysis cell is a high-temperature PEM electrolysis cell.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention combines the preparation processes of the proton exchange membrane and the membrane electrode catalyst layer into a set of preparation processes, which helps to flexibly control the formulations of the perfluorosulfonic acid resin and catalyst in the proton exchange membrane and on the catalyst layer, thereby avoiding problems such as interface resistance and low proton transfer efficiency caused by different processes and structures of the membrane and catalyst layer.

[0031] 2. The integrated membrane electrode developed by the present invention can be applied to PEM water electrolysis and fuel cells in a wide temperature range (60-150°C) and a wide humidity range (RH10-100%). The nano-water-retaining particles are simultaneously carried in the membrane and the catalyst layer, which can effectively improve the proton transmission capacity of the membrane and the catalyst layer in a high-temperature and low-humidity environment, thereby improving the output power of the membrane electrode.

[0032] 3. The present invention pre-treats the PTFE porous reinforced membrane for mechanical strength, and adopts a spraying process to fill the surface and interior of the PTFE with a perfluorosulfonic acid resin with a high molecular sieve ratio, thereby improving the reinforcement layer to not only increase the mechanical strength but also store and adsorb more water molecules, thereby forming abundant proton transfer groups in the pores. Moreover, the addition of the perfluorosulfonic acid resin effectively improves the interfacial compatibility between the resin and the surface and pores of the PTFE, thereby improving the density of the membrane in the thickness direction.

[0033] 4. The present invention performs treatment on PTFE, and the interface compatibility between the resin and the surface and pores of PTFE is conducive to the hydrogen permeability of the membrane after the membrane thickness is reduced, which can reduce the thickness of the current PEM water electrolysis membrane material.

[0034] 5. The present invention adopts water-retaining agents such as molecular sieves and introduces them into the membrane's reinforcement layer, membrane body, and catalytic layer. The uniform distribution of the multi-layer structure can effectively improve the conductivity of the membrane and the proton transfer efficiency of the catalytic layer in high temperature and low humidity environments.

[0035] 6. The present invention uses an integrated coating process, which is more suitable for mass production than spray coating, helping to reduce costs. It effectively achieves "low-cost, high-efficiency, and lossless" membrane preparation and operation, thereby more quickly, safely, and efficiently performing the functions of fuel cells or electrolyzers. DETAILED DESCRIPTION

[0036] The present invention will be further described below with reference to specific examples, but the present invention is not limited thereto in any way.

[0037] Example 1

[0038] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0039] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray nano water-retaining particles and perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of 1 μm and a porosity of 40%. The mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:1, and the spraying load is 1 mg / cm 2 , after drying at 40°C, a pre-treated reinforcement layer is formed;

[0040] Preparation of the casting slurry used in steps 2 and 3: 1g of 1nm TiO2 nano-water-retaining particles and 10g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, the ethanol concentration is 10wt.%, and the perfluorosulfonic acid resin concentration is: 2wt.%.

[0041] 2: Spread a layer of PE protective film on a 40℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 40μm, the coating speed is 0.1cm / s, the drying time is controlled at 10 seconds, and the temperature is 60℃;

[0042] 3: Then, one side of the pretreated reinforcement layer is laid flat on the wet film layer, and then the other side is coated with the casting slurry to form a wet film layer. The wet film thickness is controlled at 100 μm, the coating speed is 0.1 cm / s, the drying time is controlled at 10 seconds, and the temperature is 60°C. Repeat this step once to obtain a proton exchange reinforcement membrane with a thickness of 10 μm.

[0043] 4: Slurry 1 containing TiO2 nano-water-retaining particles and catalyst is coated on the proton exchange enhanced membrane obtained in step 3. The coating speed is 0.5 mm / s, the coating temperature is 40°C, and the catalyst loading is 0.2 mg / cm 2 Among them, the catalyst slurry 1 configuration: 1g1nm TiO2 nano-water-retaining particles and 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0044] 5: Peel off the film obtained in step 4 from the PE protective film and adsorb it directly on the vacuum platform. Coat the slurry 2 containing nano water-retaining particles and catalyst on one side of the moisturizing layer obtained in step 2. The coating speed is 0.5 mm / s, the coating temperature is 40°C, and the catalyst loading is 0.2 mg / cm 2 Among them, the configuration of the slurry containing nano water-retaining particles and catalyst 2: 1g of 1nm TiO2 nano water-retaining particles and 5g catalyst 20wt% Pt / C, Pt black was added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0045] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, with a hot pressing temperature of 70°C.

[0046] Example 2

[0047] The perfluorosulfonic acid resin in this embodiment adopts a long side chain perfluorosulfonic acid resin.

[0048] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray nano water-retaining particles and perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of 10 μm and a porosity of 85%. The mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:5, and the spraying load is 10 mg / cm 2 , after drying at 60°C, a pre-treated reinforcement layer is formed;

[0049] Preparation of the casting slurry used in steps 2 and 3: 1g of 20nm ZSM35 nano-water-retaining particles and 200g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, with the n-propanol concentration being 90wt.% and the perfluorosulfonic acid resin concentration being 10wt.%.

[0050] 2: Spread a layer of PET protective film on a vacuum adsorption coating platform at 80℃, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 150μm, the coating speed is 5cm / s, the drying time is controlled at 60 seconds, and the temperature is 90℃;

[0051] 3: Then, one side of the pretreated reinforcement layer is laid flat on the wet film layer, and then the casting slurry is coated on the other side to form a wet film layer. The wet film thickness is controlled at 500 μm, the coating speed is 5 cm / s, the drying time is controlled at 200 seconds, and the temperature is 90°C. Repeat this step 10 times to obtain a proton exchange reinforcement membrane with a thickness of 100 μm.

[0052] 4: Coat the proton exchange membrane with slurry 1 containing ZSM35 nano water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 90°C, and a catalyst loading of 3 mg / cm 2 ; Among them, the catalyst slurry 1 configuration: 1g20nm ZSM35 nano water-retaining particles and 20g catalyst iridium black were added to the dispersant, the dispersing agent was alcohol water, and the n-propanol dispersant concentration was 20g / L;

[0053] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform. Apply slurry 2 containing nano water-retaining particles and catalyst on one side of the moisturizing layer obtained in step 2. The coating speed is 5 mm / s, the coating temperature is 90°C, and the catalyst loading is 1 mg / cm 2 ; Among them, the slurry is configured as 2: 1g of 20nm ZSM35 nano-water-retaining particles and 20g of catalyst 90wt% Pt / C are added to the dispersant, the dispersing agent is alcohol water, and the concentration of n-propanol dispersant is 1-20g / L;

[0054] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 150°C.

[0055] Example 3

[0056] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0057] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray nano water-retaining particles and perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of 5μm and a porosity of 55%. The mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:2, and the spraying load is 2mg / cm 2 , after drying at 50°C, a pre-treated reinforcement layer is formed;

[0058] Preparation of the casting slurry used in steps 2 and 3: 1g of 10nm ZSM5 nano water-retaining particles and 100g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, with a propanol concentration of 50wt.% and a perfluorosulfonic acid resin concentration of 60wt.%.

[0059] 2: Spread a layer of PE protective film on a 60°C vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 100μm, the coating speed is 3cm / s, the drying time is controlled at 40 seconds, and the temperature is 70°C;

[0060] 3: Then, one side of the pretreated reinforcement layer is laid flat on the wet film layer, and then the casting slurry is coated on the other side to form a wet film layer. The wet film thickness is controlled at 300 μm, the coating speed is 3 cm / s, the drying time is controlled at 100 seconds, and the temperature is 70°C. Repeat this step 5 times to obtain a proton exchange reinforcement membrane with a thickness of 50 μm.

[0061] 4: Coat the proton exchange membrane with slurry 1 containing ZSM5 nano water-retaining particles and catalyst at a coating speed of 3 mm / s, a coating temperature of 50°C, and a catalyst loading of 1 mg / cm 2 ; Among them, the catalyst slurry 1 configuration: 1g10nm ZSM5 nano water-retaining particles and 10g catalyst Pt black were added to the dispersant, the dispersing agent was alcohol water, and the propanol dispersant concentration was 10g / L;

[0062] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform. Apply slurry 2 containing nano water-retaining particles and catalyst on one side of the moisturizing layer obtained in step 2. The coating speed is 2.5 mm / s, the coating temperature is 50°C, and the catalyst loading is 0.8 mg / cm 2 ; Among them, the slurry containing nano water-retaining particles and catalyst is 2 configurations: 1g of 10nm ZSM5 nano water-retaining particles and 10g catalyst 70wt% Pt / C added to the dispersant, the dispersing agent is alcohol water, the propanol dispersant concentration is 10g / L;

[0063] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, and hot press the temperature to 90°C.

[0064] Example 4

[0065] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0066] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray nano water-retaining particles and perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of 7μm and a porosity of 7%. The mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:3, and the spraying load is 70mg / cm 2 , after drying at 50°C, a pre-treated reinforcement layer is formed;

[0067] Preparation of the casting slurry used in steps 2 and 3: 1g of 10nm TiO2 nano-water-retaining particles and 50g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, the n-propanol concentration is 10-90wt.%, and the perfluorosulfonic acid resin concentration is 10wt.%.

[0068] 2: Spread a layer of PET protective film on a 50℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 90μm, the coating speed is 3cm / s, the drying time is controlled at 50 seconds, and the temperature is 70℃;

[0069] 3: Then, one side of the pretreated reinforcement layer is laid flat on the wet film layer, and then the casting slurry is coated on the other side to form a wet film layer. The wet film thickness is controlled at 400 μm, the coating speed is 5 cm / s, the drying time is controlled at 200 seconds, and the temperature is 90°C. Repeat this step 10 times to obtain a proton exchange reinforcement membrane with a thickness of 100 μm.

[0070] 4: Coat the proton exchange membrane with slurry 1 containing ZSM35 nano water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 90°C, and a catalyst loading of 3 mg / cm 2 ; Among them, slurry 1 configuration: 1g20nm ZSM35 nano water-retaining particles and 20g catalyst iridium black are added to the dispersant, the dispersing agent is alcohol water, and the concentration of n-propanol dispersant is 20g / L;

[0071] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform. Apply slurry 2 containing nano water-retaining particles and catalyst on one side of the moisturizing layer obtained in step 2. The coating speed is 5 mm / s, the coating temperature is 90°C, and the catalyst loading is 1 mg / cm 2; Among them, slurry 2 configuration: 1g of 20nm ZSM35 nano-water-retaining particles and 20g catalyst 90wt% Pt / C added to the dispersant, the dispersing agent is alcohol water, n-propanol dispersant concentration is 1-20g / L;

[0072] 6: The CCM, gas diffusion layer, and polyester frame are packaged into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 150°C. The polyester frame is packaged into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 70-150°C.

[0073] Example 5

[0074] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0075] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray nano water-retaining particles and perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of 1 μm and a porosity of 40%. The mass ratio of nano water-retaining particles to perfluorosulfonic acid resin is 1:3, and the spraying load is 70 mg / cm 2 , after drying at 50°C, a pre-treated reinforcement layer is formed;

[0076] Preparation of the casting slurry used in steps 2 and 3: 1g of 10nm TiO2 nano-water-retaining particles and 50g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, with a n-propanol concentration of 10% and a perfluorosulfonic acid resin concentration of 5wt.%.

[0077] 2: Spread a layer of PET protective film on a 50℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 90μm, the coating speed is 3cm / s, the drying time is controlled at 50 seconds, and the temperature is 70℃;

[0078] 3: Then, one side of the pretreated reinforcement layer is laid flat on the wet film layer, and then the other side is coated with the casting slurry to form a wet film layer. The wet film thickness is controlled at 400 μm, the coating speed is 5 cm / s, the drying time is controlled at 200 seconds, and the temperature is 90°C. Repeat the coating of the casting slurry 10 times to obtain a proton exchange reinforcement membrane with a thickness of 100 μm.

[0079] 4: Coat the proton exchange membrane with slurry 1 containing ZSM35 nano water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 60°C, and a catalyst loading of 1 mg / cm 2 ; Among them, slurry 1 configuration: 1g of 20nm ZSM35 nano water-retaining particles and 20g of catalyst iridium black were added to the dispersant, the dispersing agent was alcohol water, and the concentration of n-propanol dispersant was 20g / L;

[0080] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform. Apply slurry 2 containing nano water-retaining particles and catalyst on one side of the moisturizing layer obtained in step 2. The coating speed is 3.5 mm / s, the coating temperature is 70°C, and the catalyst loading is 1 mg / cm 2 ; Among them, slurry 2 configuration: 1g of 20nm ZSM35 nano-water-retaining particles and 20g catalyst 90wt% Pt / C added to the dispersant, the dispersing agent is alcohol water, n-propanol dispersant concentration is 1-20g / L;

[0081] 6: The CCM, gas diffusion layer, and polyester frame are packaged into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 120°C. The polyester frame is packaged into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 70-150°C.

[0082] Comparative Example 1: PTFE is not used as the reinforcement layer;

[0083] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0084] 1: Preparation of casting slurry: 1g of 1nm TiO2 nano water-retaining particles and 10g of perfluorosulfonic acid resin are dispersed in an alcohol aqueous solution, the ethanol concentration is 10wt.%, and the perfluorosulfonic acid resin concentration is: 2wt.%.

[0085] 2: Spread a layer of PE protective film on a 40℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 40μm, the coating speed is 0.1cm / s, the drying time is controlled at 10 seconds, and the temperature is 60℃;

[0086] 3: Apply the casting slurry to form a wet film layer with a wet film thickness of 100 μm, a coating speed of 0.1 cm / s, a drying time of 10 seconds, and a temperature of 60°C; repeat this step once to obtain a proton exchange enhanced membrane with a thickness of 10 μm;

[0087] 4: Coat the proton exchange membrane with slurry 1 containing TiO2 nano-water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, slurry 1 configuration: 1g1nm TiO2 nano-water-retaining particles and 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0088] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform and apply slurry 2. The coating speed is 0.5 mm / s, the coating temperature is 40 ° C, and the catalyst loading is 0.2 mg / cm 2 Among them, slurry 2 configuration: 1g of 1nm TiO2 nano-water-retaining particles and 5g catalyst 20wt% Pt / C, Pt black was added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0089] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, with a hot pressing temperature of 70°C.

[0090] Comparative Example 2: PTFE was used as the reinforcement layer without any other modification, and the casting slurry did not contain a water-retaining agent;

[0091] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0092] 1: Use PTFE as the reinforcement layer without other modifications;

[0093] 2: Spread a layer of PE protective film on a 40℃ vacuum adsorption coating platform, and apply the casting slurry perfluorosulfonic acid resin on the protective film to form a wet film layer. The wet film thickness is controlled at 40μm, the coating speed is 0.1cm / s, the drying time is controlled at 10 seconds, and the temperature is 60℃;

[0094] 3: Then, lay the PTFE reinforcement layer flat on the wet membrane layer, and then apply the casting slurry perfluorosulfonic acid resin to form a wet membrane layer. The wet membrane thickness is controlled at 100 μm, the coating speed is 0.1 cm / s, the drying time is controlled at 10 seconds, and the temperature is 60°C. Repeat this step once to obtain a proton exchange reinforced membrane with a thickness of 10 μm.

[0095] 4: Coat the proton exchange membrane with slurry 1 containing TiO2 nano-water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, slurry 1 configuration: 1g1nm TiO2 nano-water-retaining particles and 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0096] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform and apply slurry 2. The coating speed is 0.5 mm / s, the coating temperature is 40 ° C, and the catalyst loading is 0.2 mg / cm 2Among them, slurry 2 configuration: 1g of 1nm TiO2 nano-water-retaining particles and 5g catalyst 20wt% Pt / C, Pt black was added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0097] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, with a hot pressing temperature of 70°C.

[0098] Comparative Example 3: Pretreated PTFE was used as the reinforcement layer, and the casting slurry did not contain a water-retaining agent;

[0099] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0100] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray perfluorosulfonic acid resin dispersed in alcohol water into a porous PTFE membrane with a thickness of μm and a porosity of 40%. The spray load is 1 mg / cm 2 , after drying at 40 ° C, a pre-treated reinforcement layer is formed; the casting slurry used in steps 2 and 3 is prepared: 10-200g perfluorosulfonic acid resin is dispersed in an alcohol aqueous solution, the ethanol concentration is 10wt.%, the perfluorosulfonic acid resin concentration is: 2wt.%.

[0101] 2: Spread a layer of PE protective film on a 40℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 40μm, the coating speed is 0.1cm / s, the drying time is controlled at 10 seconds, and the temperature is 60℃;

[0102] 3: Then, the pre-treated reinforcement layer is laid flat on the wet film layer, and then the casting slurry is applied to form a wet film layer. The wet film thickness is controlled at 100 μm, the coating speed is 0.1 cm / s, the drying time is controlled at 10 seconds, and the temperature is 60°C. Repeat this step once to obtain a proton exchange reinforcement membrane with a thickness of 10 μm.

[0103] 4: Coat the proton exchange membrane with slurry 1 containing TiO2 nano-water-retaining particles and catalyst at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, slurry 1 configuration: 1g1nm TiO2 nano-water-retaining particles and 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0104] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform and apply slurry 2. The coating speed is 0.5 mm / s, the coating temperature is 40 ° C, and the catalyst loading is 0.2 mg / cm 2Among them, slurry 2 configuration: 1g of 1nm TiO2 nano-water-retaining particles and 5g catalyst 20wt% Pt / C, Pt black was added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0105] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, with a hot pressing temperature of 70°C.

[0106] Comparative Example 4: PTFE was used as the reinforcement layer, and no water-retaining agent was added to the membrane and the catalyst layer;

[0107] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0108] 1. Preparation of pretreatment reinforcement layer: Use a sprayer to spray perfluorosulfonic acid resin dispersed in alcohol water on the porous PTFE membrane with a thickness of μm and a porosity of 40%. The mass ratio of perfluorosulfonic acid resin is 1:1, and the spray load is 1 mg / cm 2 , after drying at 40°C, a pre-treated reinforcement layer is formed;

[0109] Preparation of the casting slurry used in steps 2 and 3: 10-200g of perfluorosulfonic acid resin is dispersed in an alcohol aqueous solution, the ethanol concentration is 10wt.%, and the perfluorosulfonic acid resin concentration is 2wt.%.

[0110] 2: Spread a layer of PE protective film on a 40℃ vacuum adsorption coating platform, apply the casting slurry on the protective film to form a wet film layer. The wet film thickness is controlled at 40μm, the coating speed is 0.1cm / s, the drying time is controlled at 10 seconds, and the temperature is 60℃;

[0111] 3: Then, the pre-treated reinforcement layer is laid flat on the wet film layer, and then the casting slurry is applied to form a wet film layer. The wet film thickness is controlled at 100 μm, the coating speed is 0.1 cm / s, the drying time is controlled at 10 seconds, and the temperature is 60°C. Repeat this step once to obtain a proton exchange reinforcement membrane with a thickness of 10 μm.

[0112] 4: Coat the proton exchange membrane with the catalyst slurry 1 at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, slurry 1 configuration: 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0113] 5: After peeling off the film from the protective film, directly adsorb it on the vacuum platform and apply slurry 2. The coating speed is 0.5 mm / s, the coating temperature is 40 ° C, and the catalyst loading is 0.2 mg / cm 2; Among them, slurry 2 configuration: 5g catalyst 20wt% Pt / C, Pt black added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0114] 6: Encapsulate the CCM, gas diffusion layer, and polyester frame into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cell, with a hot pressing temperature of 70°C.

[0115] Comparative Example 5: A commercial membrane was used as the proton exchange membrane, and a catalytic layer was directly coated on the commercial membrane without adding a water-retaining agent;

[0116] The perfluorosulfonic acid resin in this embodiment adopts a short side chain perfluorosulfonic acid resin, and the short side chain molecular structure is

[0117] The catalyst slurry 1 was coated on the proton exchange membrane at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, slurry 1 configuration: 5g catalyst Pt / C added to the dispersant, the dispersing agent is alcohol water, the ethanol dispersant concentration is 1g / L;

[0118] After peeling off the protective film, the film was directly adsorbed on the vacuum platform and coated with slurry 2 at a coating speed of 0.5 mm / s, a coating temperature of 40°C, and a catalyst loading of 0.2 mg / cm 2 ; Among them, the slurry is configured as 2: 5g catalyst 20wt% Pt / C, Pt black is added to the dispersant, the dispersing agent is alcohol water, and the ethanol dispersant concentration is 1g / L;

[0119] The CCM, gas diffusion layer, and polyester frame are packaged into a membrane electrode to form an integrated membrane electrode for water electrolysis and fuel cells. The hot pressing temperature is 70°C.

[0120] The membrane electrodes prepared in the examples and comparative examples were tested for mechanical strength, electrical conductivity, electrolytic performance, fuel cell performance, and hydrogen permeability. Conductivity testing was performed at 120°C, 40% humidity, and 100°C, 30% humidity. Tensile strength was tested according to the national standard (GB / T20042.3-2009). Hydrogen permeability was tested using an electrochemical method.

[0121] In comparative example 1, PTFE is not used as the reinforcement layer; the mechanical strength is significantly reduced. It can be seen that the reinforcement layer used in the present invention effectively improves the mechanical strength of the membrane electrode.

[0122] Comparative Example 2: PTFE is used as the reinforcement layer, and the water-retaining agent is not sprayed on the reinforcement layer, and the resin is directly coated. The results show that the mechanical strength is less increased when the resin is not sprayed on the reinforcement layer.

[0123] Comparative Example 3: PTFE was used as the reinforcing layer, and perfluorosulfonic acid resin was sprayed by spraying, but no water-retaining agent was added. However, a water-retaining agent was added to the catalytic layer. The results show that the spraying method improved the interfacial compatibility on the surface of the reinforcing layer to a certain extent, and the mechanical strength remained unchanged, but the water retention capacity in a low-humidity environment was poor and the electrical conductivity was low. However, with the addition of a water-retaining agent in the catalytic layer, the performance was better than that of Comparative Example 2.

[0124] Comparative Example 4: PTFE is used as the reinforcement layer, and no water-retaining agent is added to the membrane and the catalyst layer; the results show that the mechanical strength is improved, but the water retention capacity in a low-humidity environment is poor, the electrical conductivity is low, and the battery performance is poor.

[0125] Comparative Example 5: A commercial membrane was used as the proton exchange membrane, and a catalytic layer was directly coated on the commercial membrane without adding a water-retaining agent. The results show that the coating caused significant damage to the membrane during the preparation process, resulting in the worst mechanical strength and low battery performance.

[0126] Table 1 Performance of membrane electrode

[0127] This specific embodiment is merely an explanation of the present invention and is not intended to limit the present invention. After reading this specification, those skilled in the art may make non-creative modifications to this embodiment as needed. However, as long as such modifications are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A method for preparing an integrated membrane electrode for water electrolysis and fuel cells, characterized in that: The following steps are involved: Step 1: spraying water-retaining nanoparticles and perfluorosulfonic acid resin dispersed in an alcohol aqueous solution into a porous PTFE membrane, and forming a pre-treated reinforcement layer after drying; Step 2: Apply the casting slurry on one side of the PE / PET protective film, and dry it at 60-90°C for 10-60 seconds to form a wet film layer I in an incompletely dried state, and the wet thickness of the wet film layer I is controlled at 40-150 μm; Step 3: Lay one side of the pretreated reinforcement layer obtained in step 1 on the wet film layer I, then apply the casting slurry on the other side of the pretreated reinforcement layer, dry it at 60-90°C for 10-200 seconds to form a wet film layer II in an incompletely dried state, repeat this step 1-10 times, and control the wet thickness of the wet film layer II to 100-500 μm each time, and then obtain a proton exchange enhanced membrane; in steps 2 and 3, the casting slurry is: an alcohol aqueous solution containing nano water-retaining particles and perfluorosulfonic acid resin; Step 4: Slurry 1 is coated on the wet film layer II in step 3 and dried. The slurry 1 includes water-retaining nanoparticles and a catalyst. The catalyst loading is 0.2-3 mg / cm 2 ; Step 5: Peel off the film completed in step 4 from the PE / PET protective film, apply slurry 2 on the wet film layer I, and dry to obtain CCM. The slurry 2 includes water-retaining nanoparticles and a catalyst, and the catalyst loading is 0.2-1 mg / cm 2 ; Step 6: Hot pressing and packaging to form an integrated membrane electrode for water electrolysis and fuel cells.

2. The method according to claim 1, characterized in that: In step 1: the thickness of the porous PTFE membrane is 1-10 μm, the porosity is 40-85%, the mass ratio of the nano water-retaining particles to the perfluorosulfonic acid resin is 1:1-5, and the spraying load is 1-10 mg / cm 2 ; Drying temperature is 40-60°C to form a pre-treated reinforcement layer; In step 2: the PE / PET protective film is laid flat on a 40-80°C vacuum adsorption coating platform; the coating speed of the casting slurry is 0.1-5cm / s; In step 3: the coating speed is 0.1-5 cm / s; In step 4: the catalyst in slurry 1 is one of a Pt-based and an iridium-based catalyst, the mass ratio of the water-retaining agent nanoparticles to the catalyst is 1:5-20, the dispersing agent is an alcohol aqueous solution; the coating speed is 0.5-5 mm / s, the coating temperature is 40-90° C.; the concentration of the alcohol aqueous solution is 1-20 g / L; In step 5: the catalyst in slurry 2 is one of a Pt-based noble metal catalyst and a non-noble metal catalyst, the mass ratio of water-retaining agent nanoparticles to the catalyst is 1:5-20, the dispersing agent is an alcohol aqueous solution; the coating speed is 0.5-5 mm / s, the coating temperature is 40-90° C.; the concentration of the alcohol aqueous solution is 1-20 g / L; In step 6: the CCM obtained in step 5 is packaged with the gas diffusion layer and the polyester frame by hot pressing to form a membrane electrode; the hot pressing temperature is 70-150°C.

3. The method according to claim 1, characterized in that: In step 1-6, the nano water-retaining particles are one or more of TiO2, ZSM5, and ZSM35 molecular sieves, and the particle size of the nano particles is 1-20 nm.

4. The method according to claim 1, characterized in that: In steps 2 and 3, the mass ratio of the nano water-retaining particles to the perfluorosulfonic acid resin in the casting slurry is 1:10-200, and the concentration of the perfluorosulfonic acid resin is 2-10wt.%.

5. The method according to claim 1 or 4, characterized in that: The alcohol in the alcohol aqueous solution is independently selected from one or more mixtures of ethanol, n-propanol, isopropanol, methanol and n-butanol.

6. The method according to claim 1 or 4, characterized in that: Perfluorosulfonic acid resin is a long side chain resin or a short side chain perfluorosulfonic acid resin, wherein the short side chain molecular structure is One or more of .

7. An integrated membrane electrode for water electrolysis and fuel cell obtained by the preparation method according to any one of claims 1 to 6.

8. Use of the integrated membrane electrode as claimed in claim 7 as a membrane electrode in a water electrolysis cell and a fuel cell.

9. The use according to claim 8, characterized in that: The fuel cell is a high-temperature proton exchange membrane fuel cell with an anhydrous system, a low-humidity air intake environment, and an operating temperature of 100-150° C.; the water electrolysis cell is a high-temperature PEM electrolysis cell.

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