A proton exchange membrane with catalytic hydrogen blocking function and a preparation method and application thereof

Abstract

The present application relates to a proton exchange membrane with catalytic hydrogen blocking function and its preparation method and application. The proton exchange membrane with catalytic hydrogen blocking function comprises a proton conductive base film layer, a first catalytic hydrogen blocking function layer arranged on one side surface of the proton conductive base film layer, and optionally a second catalytic hydrogen blocking function layer arranged on the other side surface of the proton conductive base film layer; the first catalytic hydrogen blocking function layer and the second catalytic hydrogen blocking function layer each independently comprise a platinum group metal catalyst and a proton conductive ionomer; the loading amount of the platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen blocking function is 0.001-0.1 mg / cm 2 The proton exchange membrane with catalytic hydrogen blocking function provided by the present application can actively consume the permeated hydrogen on the membrane surface or the near interface region, and convert the hydrogen and oxygen into water through in-situ catalytic reaction, thereby reducing the hydrogen cross permeation without significantly increasing the electric resistance.

Description

Technical Field

[0001] This invention belongs to the field of water electrolysis hydrogen production technology, specifically relating to a proton exchange membrane with catalytic hydrogen inhibition function, its preparation method and application. Background Technology

[0002] In proton exchange membrane (PEM) water electrolysis, hydrogen is generated on the cathode side. However, due to the dissolution and permeation of hydrogen within the PEM, its hydrogen barrier capacity is limited, allowing some hydrogen to pass through and enter the anode side—a phenomenon known as hydrogen cross-permeation. This leads to: increased hydrogen content in the oxygen-generating gas at the anode, posing a safety hazard; and decreased effective hydrogen production, resulting in reduced system energy efficiency. Under high temperature and high pressure conditions, hydrogen cross-permeation is even more severe, thus placing higher demands on the stability of the PEM and the system.

[0003] Existing technologies for reducing hydrogen cross-permeation mainly include passive barrier methods such as increasing membrane thickness, introducing inorganic fillers, optimizing membrane microstructure, and using multilayer membrane structures. However, simply increasing membrane thickness will significantly increase sheet resistance and reduce electrolysis efficiency; while the preparation process of multilayer membrane structures is complex, and passive barrier methods cannot fundamentally eliminate the permeated hydrogen.

[0004] Therefore, there is a need to develop a proton exchange membrane that can reduce hydrogen cross-permeation without significantly increasing resistance. Summary of the Invention

[0005] This invention aims to provide a proton exchange membrane with catalytic hydrogen blocking function, its preparation method, and its application. By introducing a catalytic hydrogen blocking functional layer containing a platinum group metal catalyst on the surface of the proton conductive base membrane, hydrogen permeating into the catalytic hydrogen blocking functional layer region reacts with oxygen in situ to generate water, thereby significantly reducing hydrogen cross-permeation and improving the safety and energy efficiency of the water electrolysis system. At the same time, it does not cause a significant increase in the sheet resistance and electrolysis voltage of the proton exchange membrane with catalytic hydrogen blocking function.

[0006] To achieve this objective, the present invention adopts the following technical solution: In a first aspect, the present invention provides a proton exchange membrane with catalytic hydrogen blocking function. The proton exchange membrane includes a proton-conductive base film layer, a first catalytic hydrogen blocking functional layer disposed on one surface of the proton-conductive base film layer, and optionally a second catalytic hydrogen blocking functional layer disposed on the other surface of the proton-conductive base film layer. Each of the first and second catalytic hydrogen blocking functional layers independently includes a platinum group metal catalyst and a proton-conductive ionomer. The loading of the platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen blocking function is 0.001~0.1 mg / cm³. 2 For example, 0.002 mg / cm 20.004 mg / cm 2 0.006 mg / cm 2 0.008 mg / cm 2 0.01 mg / cm 2 0.02 mg / cm 2 0.04 mg / cm 2 0.06 mg / cm 2 Or 0.08 mg / cm 2 wait.

[0007] In this invention, by introducing a first catalytic hydrogen barrier functional layer containing a platinum group metal catalyst and an optional second catalytic hydrogen barrier functional layer on the surface of a proton-conductive base film, hydrogen that permeates into the regions of the first catalytic hydrogen barrier functional layer and the optional second catalytic hydrogen barrier functional layer reacts with oxygen in situ to generate water, thereby actively consuming the permeated hydrogen.

[0008] In this invention, when the proton exchange membrane with catalytic hydrogen blocking function is used in a water electrolysis device, the first catalytic hydrogen blocking functional layer and optionally the second catalytic hydrogen blocking functional layer do not contact the gas diffusion layer in the water electrolysis device, and do not contain a porous mass transfer framework structure for electrode reactions. They are not used as electrode reaction layers; their function is to catalyze the permeation of hydrogen and oxygen to generate water, thereby reducing hydrogen cross-permeation. Before reaching the anode side of the water electrolysis device or in the near-anode interface region, hydrogen is reconstituted into water by the proton exchange membrane with catalytic hydrogen blocking function, achieving a synergistic mechanism of active consumption and passive barrier. This reduces the accumulation of hydrogen on the anode side of the water electrolysis device from the source, lowers the risk of gas mixing, and improves the safety and energy efficiency of the water electrolysis system, without significantly increasing resistance.

[0009] In this invention, the loading of platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen inhibition function is controlled to be 0.001~0.1 mg / cm³. 2 This ensures that the material has sufficient catalytic activity without forming a thick catalytic layer like traditional electrode layers, thereby minimizing the impact on proton exchange membrane resistance and reaction overpotential.

[0010] Preferably, the thickness of the first catalytic hydrogen barrier functional layer and the second catalytic hydrogen barrier functional layer is independently 0.05~5 μm (e.g. 0.1 μm, 0.5 μm, 1.0 μm, 1.5 μm, 2.0 μm, 2.5 μm, 3.0 μm, 3.5 μm, 4.0 μm or 4.5 μm, etc.), and more preferably 0.1~1 μm.

[0011] In this invention, the thickness of the first catalytic hydrogen barrier functional layer and the second catalytic hydrogen barrier functional layer can be controlled by coating. The thickness should not be too thick, otherwise the resistance will be too high. For example, the thickness can be 1~30μm by solution casting. A thickness ≤5μm is considered ultrathin. Ultrathin thickness can be achieved by spraying. Ultrathin thickness can reduce resistance.

[0012] Preferably, the loading of platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen inhibition function is 0.002~0.02 mg / cm³. 2 (e.g., 0.004 mg / cm) 2 0.006 mg / cm 2 0.008 mg / cm 2 0.010 mg / cm 2 0.012 mg / cm 2 0.014 mg / cm 2 0.016 mg / cm 2 Or 0.018 mg / cm 2 wait).

[0013] In this invention, the loading of platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen blocking function refers to the total loading of platinum group metal catalyst in the first catalytic hydrogen blocking functional layer and the second catalytic hydrogen blocking functional layer.

[0014] In this invention, the first and second catalytic hydrogen barrier functional layers are thin, the loading of platinum group metal catalysts is much lower than that of the electrode layers of the water electrolysis device, and the first and second catalytic hydrogen barrier functional layers are not used as electrode layers. Therefore, they do not significantly increase the sheet resistance and volume resistance of the overall membrane material, and have little impact on the water electrolysis voltage.

[0015] Preferably, the platinum group metal catalyst comprises a platinum group metal and optionally a support.

[0016] Preferably, the platinum group metals include any one or a combination of at least two of platinum (Pt), platinum alloys, palladium (Pd), palladium alloys, rhodium (Rh), or rhodium alloys.

[0017] Preferably, the platinum group metals include platinum and / or platinum-palladium alloys.

[0018] Preferably, the support comprises a carbon support and / or an inorganic oxide support.

[0019] For example, the carbon support includes carbon black and / or carbon nanotubes; the inorganic oxide support includes any one or a combination of at least two of TiO2, SiO2 or ZrO2.

[0020] For example, the platinum group metal catalyst includes Pt / C and / or Pt / TiO2. Pt / C refers to a platinum group metal catalyst composed of a carbon support and platinum; Pt / TiO2 refers to a platinum group metal catalyst composed of an inorganic oxide support TiO2 and platinum.

[0021] Preferably, the proton-conducting ionomer comprises a perfluorosulfonic acid resin ionomer.

[0022] Preferably, the perfluorosulfonic acid resin ionomer comprises short-side-chain perfluorosulfonic acid resin and / or long-side-chain perfluorosulfonic acid resin, and more preferably short-side-chain perfluorosulfonic acid resin.

[0023] In this invention, the short-side-chain perfluorosulfonic acid resin is a perfluorosulfonic acid resin with 3 to 5 carbon atoms in the side chain structure from the main chain to the sulfonic acid group; the long-side-chain perfluorosulfonic acid resin is a perfluorosulfonic acid resin with more than 5 carbon atoms in the side chain structure from the main chain to the sulfonic acid group.

[0024] Preferably, the proton-conductive base film layer comprises a perfluorosulfonic acid type proton exchange membrane and / or an enhanced proton exchange membrane.

[0025] Preferably, the thickness of the proton-conductive base film is 30~150 μm, such as 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm or 140 μm.

[0026] Preferably, the perfluorosulfonic acid type proton exchange membrane comprises a short-side-chain perfluorosulfonic acid resin membrane and / or a long-side-chain perfluorosulfonic acid resin membrane.

[0027] Preferably, the reinforcing structure of the enhanced proton exchange membrane comprises an aromatic polymer mesh.

[0028] Preferably, the aromatic polymer mesh includes a polyether ether ketone (PEEK) mesh and / or a polyphenylene sulfide (PPS) mesh.

[0029] In a second aspect, the present invention provides a method for preparing a proton exchange membrane with catalytic hydrogen blocking function as described in the first aspect, the method comprising the following steps: forming a first catalytic hydrogen blocking functional layer and optionally a second catalytic hydrogen blocking functional layer on a proton conductive base film layer to obtain the proton exchange membrane with catalytic hydrogen blocking function.

[0030] Preferably, the preparation method includes the following steps: (1) preparing a catalytic hydrogen barrier functional slurry by combining a platinum group metal catalyst and a proton-conductive ionomer; (2) coating the catalytic hydrogen barrier functional slurry obtained in step (1) onto one or both surfaces of the proton-conductive base film layer, and obtaining the proton exchange membrane with catalytic hydrogen barrier function by drying and heat treatment.

[0031] Preferably, the coating in step (2) includes any one or a combination of at least two of impregnation, casting or spraying.

[0032] Preferably, the drying temperature is 40~120℃, such as 50℃, 60℃, 70℃, 80℃, 90℃, 100℃ or 110℃.

[0033] Preferably, the drying time is 1 to 10 hours, such as 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, or 9 hours.

[0034] Preferably, the drying process includes step-by-step drying, which includes a first drying and a second drying. The temperature of the first drying is 40~80℃, such as 45℃, 50℃, 55℃, 60℃, 65℃, 70℃ or 75℃, etc., and the temperature of the second drying is 80~120℃, such as 85℃, 90℃, 95℃, 100℃, 105℃, 110℃ or 115℃, etc.

[0035] Preferably, the heat treatment temperature is 50~220℃ (e.g., 60℃, 80℃, 100℃, 120℃, 140℃, 160℃, 180℃, 200℃ or 210℃, etc.), and more preferably 120~200℃.

[0036] Preferably, the heat treatment time is 1 to 10 hours (e.g., 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, or 9 hours).

[0037] In this invention, heat treatment helps to form a dense first catalytic hydrogen barrier functional layer and a second catalytic hydrogen barrier functional layer.

[0038] Preferably, the preparation method includes the following steps: (I) preparing a catalytic hydrogen barrier functional slurry by combining a platinum group metal precursor and a proton-conductive ionomer; (II) coating the catalytic hydrogen barrier functional slurry obtained in step (I) onto one or both surfaces of the proton-conductive base film layer, drying, and reducing to obtain the proton exchange membrane with catalytic hydrogen barrier function.

[0039] Preferably, the coating in step (II) includes any one or a combination of at least two of impregnation, casting or spraying.

[0040] Preferably, the reduction includes chemical reduction or electrochemical reduction.

[0041] For example, the preparation method includes the following steps: (I) preparing a catalytic hydrogen barrier functional slurry by mixing a platinum group metal precursor and a proton-conductive ionomer; (II) coating the catalytic hydrogen barrier functional slurry obtained in step (I) onto one or both surfaces of a proton-conductive base film layer to enrich the platinum group metal precursor on the surface and near-surface region of the proton-conductive base film layer, drying to form a film, and then impregnating it with a reducing agent solution to reduce the platinum group metal precursor to form platinum group metal nanoparticles. The formed platinum group metal nanoparticles are mainly distributed on the surface and near-surface region of the proton-conductive base film layer to obtain the proton exchange membrane with catalytic hydrogen barrier function.

[0042] In this invention, the preparation method possesses both process versatility and device adaptability. The first catalytic hydrogen barrier functional layer and optionally the second catalytic hydrogen barrier functional layer can be constructed on various existing proton-conducting base membranes through any one of the following processes: impregnation, casting, or spraying. Existing proton-conducting base membranes include long-side-chain perfluorosulfonic acid resin membranes (Nafion membranes), short-side-chain perfluorosulfonic acid resin membranes, and reinforced proton exchange membranes, etc. The preparation method does not require changes to the structural design of existing water electrolyzers; upgrading only the proton exchange membrane can significantly improve the risk of gas mixing. This technical route, which is "compatible with existing systems and can achieve safety upgrades at the proton exchange membrane end," has good engineering promotion value and significant practical significance.

[0043] Thirdly, the present invention provides a water electrolysis device, the water electrolysis device comprising an anode chamber, a cathode chamber, and a proton exchange membrane having a catalytic hydrogen blocking function as described in the first aspect, disposed between the anode chamber and the cathode chamber; wherein the first catalytic hydrogen blocking functional layer of the proton exchange membrane having a catalytic hydrogen blocking function is located on the side closer to the anode chamber.

[0044] Fourthly, the present invention provides the application of a proton exchange membrane with catalytic hydrogen inhibition function as described in the first aspect or a water electrolysis device as described in the third aspect in water electrolysis for hydrogen production.

[0045] Compared with the prior art, the present invention has at least the following beneficial effects: When a water electrolysis cell with a proton exchange membrane having a catalytic hydrogen barrier function, as described in this invention, is used for water electrolysis at a temperature of 80°C, an anode pressure of 2 bar (g), and a cathode pressure of 10 bar (g), compared to a water electrolysis cell made with a proton exchange membrane without a first and second catalytic hydrogen barrier functional layer, the volume fraction of hydrogen in the oxygen atmosphere generated on the anode side is reduced by ≥28%, and the voltage increase is ≤0.070 V. Preferably, the volume fraction of hydrogen in the oxygen atmosphere generated on the anode side is reduced by ≥40%, and the voltage increase is ≤0.035 V, thus reducing hydrogen cross-permeability without significantly increasing resistance. Detailed Implementation

[0046] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0047] Unless otherwise specified, the materials and equipment involved in the following detailed embodiments are all conventional materials and equipment in the art and will not affect the technical effects of the present invention.

[0048] Preparation Example 1 This preparation example provides an enhanced proton exchange membrane, which is prepared by the following method: (I) 150 g of powdered short-side-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g, model Aquivion) ® D72-25BS (manufacturer: Synensqo) was added to 850 g of an aqueous ethanol solution (ethanol to water mass ratio of 1:1) and mechanically stirred at 50 °C for 12 h to obtain a short-chain perfluorosulfonic acid resin solution.

[0049] (II) The reinforcing fabric (polyetheretherketone mesh, Swiss SEFAR mesh 17-115X145 / 58, thickness 50 μm, unit area mass 17 g / m²) will be used. 2 The fabric with an average porosity of 58% was subjected to the following treatments in sequence: ultrasonic cleaning with acetone for 10 min, rinsing with deionized water 3 times, vacuum drying at 80℃ for 2 h, and treatment under oxygen plasma with a power of 100 W, a working pressure of 30 Pa, and a time of 5 min to obtain the treated reinforced fabric.

[0050] (III) The treated reinforcing fabric obtained in step (II) is laid flat on a polished stainless steel plate. The short-side chain perfluorosulfonic acid resin solution obtained in step (I) is uniformly cast onto the surface of the treated reinforcing fabric. A precision scraper with a gap of 600 μm is used to completely impregnate the short-side chain perfluorosulfonic acid resin solution into the pores of the treated reinforcing fabric. Then, it is placed in a 60℃ oven for pre-drying for 2 h, then cooled, and the short-side chain perfluorosulfonic acid resin solution is scraped onto the surface again. It is then placed in a 60℃ oven for pre-drying for 2 h, then heated to 120℃ for drying for 1 h, and then heat-treated at 160℃ for 1 h to obtain an integrated reinforcing membrane for water electrolysis. The thickness is measured to be 85 μm using a micrometer.

[0051] (IV) Cut the integrated reinforced membrane for water electrolysis obtained in step (III) into 5 cm × 5 cm pieces, immerse them in 0.5 mol / L H2SO4 solution for 2 h to achieve protonation treatment, and then wash them 3 times with boiling deionized water until the pH of the washing solution is 6.5, with each washing time being 30 min, to obtain the reinforced proton exchange membrane, denoted as PEEK-PFSA-85.

[0052] Preparation Example 2 This preparation example provides a perfluorosulfonic acid type proton exchange membrane, which is prepared by the following method: (I) 100 g of short-side-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g, model Aquivion) ® D72-25BS (manufacturer: Synensqo) was added to 900 g of an aqueous ethanol solution (ethanol to water mass ratio of 1:1) and mechanically stirred at 50°C for 12 h to obtain a short-side-chain perfluorosulfonic acid resin solution.

[0053] (II) The short-side-chain perfluorosulfonic acid resin solution obtained in step (I) is uniformly cast onto a flat stainless steel substrate surface and coated with a scraper with a gap of 600 μm. Then, it is placed in a 60℃ oven for pre-drying for 2 h to form a resin film. After cooling, the short-side-chain perfluorosulfonic acid resin solution is coated onto the resin film surface and the steps of pre-drying in a 60℃ oven for 2 h are repeated. Then, the temperature is raised to 120℃ for drying for 1 h, followed by heat treatment at 160℃ for 1 h to obtain a short-side-chain perfluorosulfonic acid resin film with a thickness of 60 μm measured by a micrometer.

[0054] (III) The short-side chain perfluorosulfonic acid resin membrane obtained in step (II) is immersed in 0.5 mol / L sulfuric acid solution for 2 h, and then washed thoroughly with deionized water until the pH of the washing solution is 7 to obtain the perfluorosulfonic acid type proton exchange membrane, denoted as SC-PFSA-60.

[0055] Example 1 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The proton exchange membrane with catalytic hydrogen blocking function includes a proton conductive base film layer and a first catalytic hydrogen blocking functional layer disposed on one side surface of the proton conductive base film layer.

[0056] The preparation method includes the following steps: (1) 40 parts by weight of platinum group metal catalyst (commercial Pt / C catalyst slurry, with a Pt mass fraction of 20 wt.% on dry matter), 10 parts by weight of perfluorosulfonic acid resin ionomer solution (solid content of 5 wt.%) and 50 parts by weight of a mixed solvent of isopropanol and water (mass ratio of isopropanol to water of 1:1) were ultrasonically dispersed in an ice bath for 30 min to obtain a uniform catalytic hydrogen inhibition functional slurry. The viscosity of the catalytic hydrogen inhibition functional slurry at 25 °C was 50 mPa·s.

[0057] The above-mentioned perfluorosulfonic acid resin ionomer solution was prepared by the following method: Aquivion short-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g) was used. ® D72-25BS (manufacturer: Synesqo) was added to a mixed solvent of ethanol and water (ethanol to water mass ratio of 1:1), and mechanically stirred at 50°C for 12 h to obtain a perfluorosulfonic acid resin ionomer solution with a solid content of 5 wt.%.

[0058] (2) The proton-conducting base membrane (the enhanced proton exchange membrane PEEK-PFSA-85 provided in Preparation Example 1) was fixed on a vacuum adsorption stage. A catalytic hydrogen-blocking functional slurry was uniformly coated onto one side of the enhanced proton exchange membrane using a doctor blade coating method. The membrane was then dried at 60°C for 1 h and then heat-treated at 100°C for 30 min to form a continuous and dense first catalytic hydrogen-blocking functional layer with a thickness of 0.3 μm, thus obtaining the proton exchange membrane with catalytic hydrogen-blocking function. Based on the coating amount of the catalytic hydrogen-blocking functional slurry, the Pt loading was calculated to be 0.007 mg·cm³. -2 .

[0059] Example 2 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The proton exchange membrane with catalytic hydrogen blocking function includes a proton conductive base film layer, a first catalytic hydrogen blocking functional layer disposed on one side surface of the proton conductive base film layer, and a second catalytic hydrogen blocking functional layer disposed on the other side surface of the proton conductive base film layer.

[0060] The preparation method includes the following steps: (1) 30 parts by weight of platinum group metal catalyst (Pt / TiO2 catalyst, of which Pt mass fraction is 10 wt.%), 15 parts by weight of perfluorosulfonic acid resin ionomer solution (solid content is 5 wt.%) and 55 parts by weight of a mixed solvent of isopropanol and water (mass ratio of isopropanol and water is 1:1) were ultrasonically dispersed in an ice bath for 30 min to obtain a uniform catalytic hydrogen inhibition functional slurry.

[0061] The above-mentioned perfluorosulfonic acid resin ionomer solution was prepared by the following method: Aquivion short-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g) was used. ® D72-25BS (manufacturer: Synesqo) was added to a mixed solvent of ethanol and water (isopropanol and water in a mass ratio of 1:1), and mechanically stirred at 50°C for 12 h to obtain a perfluorosulfonic acid resin ionomer solution with a solid content of 5 wt.%.

[0062] (2) The catalytic hydrogen barrier functional slurry obtained in step (1) was sprayed onto both sides of the proton-conducting base membrane (the perfluorosulfonic acid type proton exchange membrane SC-PFSA-60 provided in Preparation Example 2), then dried at 60°C for 1 h, and then heat-treated at 100°C for 30 min to form the first catalytic hydrogen barrier functional layer and the second catalytic hydrogen barrier functional layer. The thickness of both the first and second catalytic hydrogen barrier functional layers was 0.2 μm. Based on the coating amount of the catalytic hydrogen barrier functional slurry, the Pt loading was calculated to be 0.012 mg·cm³. -2 .

[0063] Example 3 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The proton exchange membrane with catalytic hydrogen blocking function includes a proton conductive base film layer and a first catalytic hydrogen blocking functional layer disposed on one side surface of the proton conductive base film layer.

[0064] The preparation method includes the following steps: (1) Dissolve hexachloroplatinic acid (H2PtCl6·6H2O) in deionized water to prepare a platinum group metal precursor solution with a concentration of 0.005 mol / L.

[0065] The short-side-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g, model Aquivion) ​​was used. ® D72-25BS (manufacturer: Synensqo) was added to a mixed solvent of ethanol and water (ethanol to water mass ratio of 1:1), and mechanically stirred at 50°C for 12 h to obtain a perfluorosulfonic acid resin ionomer solution with a solid content of 5 wt.%.

[0066] 30 parts by weight of the above platinum group metal precursor solution, 20 parts by weight of the above perfluorosulfonic acid resin ionomer solution, and 50 parts by weight of a mixed solvent of isopropanol and water (the mass ratio of isopropanol to water is 1:1) were mixed and ultrasonically dispersed in an ice bath for 30 min to obtain a uniform catalytic hydrogen inhibition functional slurry.

[0067] (2) In proton-conducting substrate (Nafion) TMThe catalytic hydrogen-blocking functional slurry prepared in step (1) was sprayed onto one side of the 115 membrane and then dried at 60°C for 1 h. Subsequently, the proton-conducting base membrane was transferred to a 0.05 mol / L NaBH4 aqueous solution and reduced at room temperature (25°C) for 30 min to form Pt nanoparticles in situ on its surface. The membrane was then removed, washed, dried at 60°C for 1 h, and then heat-treated at 100°C for 30 min to form a continuous and dense first catalytic hydrogen-blocking functional layer with a thickness of 0.2 μm, thus obtaining the proton exchange membrane with catalytic hydrogen-blocking function. The Pt loading was 0.008 mg / cm³. 2 .

[0068] Example 4 This embodiment provides a proton exchange membrane with catalytic hydrogen inhibition function and its preparation method. The difference between this embodiment and Example 2 is that, in the preparation of the perfluorosulfonic acid resin ionomer solution, a short-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.43 meq / g, type Aquivion) ​​is used. ® D72-25BS (manufacturer: Synensqo) was replaced with long-side-chain perfluorosulfonic acid resin (ion exchange capacity ≈ 1.25 meq / g), and the other conditions were the same as in Example 2.

[0069] Example 5 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The difference from Example 2 is that the amount of platinum group metal catalyst (Pt / TiO2 catalyst, where the Pt mass fraction is 10 wt.%) added in step (1) is reduced. When the thickness of both the first and second catalytic hydrogen blocking functional layers is 0.2 μm, the Pt loading is calculated to be 0.0015 mg·cm³ based on the coating amount of the catalytic hydrogen blocking functional slurry. -2 Other conditions are the same as in Example 2.

[0070] Example 6 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The difference from Example 2 is that the amount of platinum group metal catalyst (Pt / TiO2 catalyst, where the Pt mass fraction is 10 wt.%) added in step (1) is increased. When the thickness of both the first and second catalytic hydrogen blocking functional layers is 0.2 μm, the Pt loading is calculated to be 0.02 mg·cm³ based on the coating amount of the catalytic hydrogen blocking functional slurry. -2 Other conditions are the same as in Example 2.

[0071] Example 7 This embodiment provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The difference from Example 2 is that the amount of platinum group metal catalyst (Pt / TiO2 catalyst, where the Pt mass fraction is 10 wt.%) added in step (1) is increased. When the thickness of both the first and second catalytic hydrogen blocking functional layers is 0.2 μm, the Pt loading is calculated to be 0.1 mg·cm³ based on the coating amount of the catalytic hydrogen blocking functional slurry. -2 Other conditions are the same as in Example 2.

[0072] Comparative Example 1 This comparative example provides a proton exchange membrane with catalytic hydrogen blocking function and its preparation method. The difference from Example 2 is that the amount of platinum group metal catalyst (Pt / TiO2 catalyst, where the Pt mass fraction is 10 wt.%) added in step (1) is reduced. When the thickness of both the first and second catalytic hydrogen blocking functional layers is 0.2 μm, the Pt loading is calculated to be 0.0005 mg·cm³ based on the coating amount of the catalytic hydrogen blocking functional slurry. -2 Other conditions are the same as in Example 2.

[0073] Comparative Example 2 This comparative example provides a proton exchange membrane with catalytic hydrogen barrier function and its preparation method. The difference between this and Example 2 is that the amount of platinum group metal catalyst (Pt / TiO2 catalyst, where the Pt mass fraction is 10 wt.%) added in step (1) is increased. When the thickness of both the first and second catalytic hydrogen barrier functional layers is 0.2 μm, the Pt loading is calculated to be 0.2 mg·cm³ based on the coating amount of the catalytic hydrogen barrier functional slurry. -2 Other conditions are the same as in Example 2.

[0074] Performance testing The proton exchange membranes with catalytic hydrogen inhibition function provided in Examples 1-7 and Comparative Examples 1-2 were assembled into a 5cm assembly. 2 A single water electrolysis cell with effective area, wherein the anode in the single water electrolysis cell is an IrO2 catalyst layer (Ir loading is 1.5 mg / cm²). 2 The cathode is a Pt / C catalyst layer (Pt loading is 0.5 mg / cm³). 2 The first catalytic hydrogen barrier layer of the proton exchange membrane with catalytic hydrogen barrier function is located on the side closer to the anode. Under operating conditions of 80°C, anode pressure of 2 bar(g), and cathode pressure of 10 bar(g), the following performance tests were conducted, where bar(g) refers to the unit of gauge pressure. The corresponding proton-conductive base membrane used in the preparation of the proton exchange membrane with catalytic hydrogen barrier function was assembled into a 5cm... 2A single water electrolysis cell with effective area was used as a control group.

[0075] (1) Hydrogen cross current density: Taking Example 1 as an example, it was measured by linear sweep voltammetry (LSV).

[0076] (2) Volume fraction of hydrogen in the oxygen atmosphere generated on the anode side: Water electrolysis single cell at 2.0 A / cm 2 The cell was run stably at a current density for 8 hours, and then the volume fraction of hydrogen in the oxygen atmosphere generated on the anode side was measured. The decrease rate of the volume fraction of hydrogen in the oxygen atmosphere generated on the anode side of the water electrolysis cell assembled with a proton exchange membrane with catalytic hydrogen inhibition function was compared with that of the water electrolysis cell assembled with a proton conductive base membrane.

[0077] (3) Voltage of a single water electrolysis cell: The voltage of a single water electrolysis cell is 2.0 A / cm. 2 The voltage of the water electrolysis cell was tested after running at a current density for 8 hours. The increase in voltage of the water electrolysis cell assembled with a proton exchange membrane with catalytic hydrogen inhibition function was compared with that of the water electrolysis cell assembled with a proton conductive base membrane.

[0078] (4) Stability: The water electrolysis single cell assembled with a proton exchange membrane with catalytic hydrogen inhibition function was stable at 2.0 A / cm. 2 Run the circuit at the specified current density for 500 hours and observe whether local cracking occurs.

[0079] The test results are shown in Tables 1 and 2 below.

[0080] Table 1 Table 2 According to the test results in Tables 1 and 2, when the water electrolysis single cell made of the proton exchange membrane with catalytic hydrogen blocking function described in Examples 1 to 7 is subjected to water electrolysis at a temperature of 80°C, an anode pressure of 2 bar (g), and a cathode pressure of 10 bar (g), compared with the water electrolysis single cell made of the proton exchange membrane without the first catalytic hydrogen blocking functional layer and optionally the second catalytic hydrogen blocking functional layer, the volume fraction of hydrogen in the oxygen atmosphere generated on the anode side is reduced by ≥28%, and the increase in voltage is ≤0.070 V. This can reduce hydrogen cross-permeation without significantly increasing resistance.

[0081] Compared to Example 2, if the short-side-chain perfluorosulfonic acid resin is replaced with the long-side-chain perfluorosulfonic acid resin in the perfluorosulfonic acid resin ionomer solution (Example 4), the volume fraction decrease rate of hydrogen in the oxygen atmosphere generated on the anode side of the prepared water electrolysis single cell is low, and the stability is worse. This may be because the choice of perfluorosulfonic acid resin ionomer and the matching of the proton-conductive base film layer will affect the continuity and interfacial impedance of the first and second catalytic hydrogen barrier functional layers, resulting in stability problems.

[0082] Compared to Example 2, if the Pt loading is low (Example 5), the decrease rate of hydrogen volume fraction in the oxygen atmosphere generated on the anode side of the prepared water electrolysis single cell is low, and the effect of reducing hydrogen cross-permeation is relatively low; if the Pt loading is high (Example 7), more platinum group metals are introduced, leading to increased interfacial polarization and ohmic impedance, and a larger increase in voltage. Therefore, the preferred loading of platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen inhibition function is 0.002~0.02 mg / cm³. 2 The proton exchange membrane with catalytic hydrogen inhibition function prepared by time has better performance.

[0083] Compared with Example 2, if the Pt loading is too low (Comparative Example 1), there are insufficient active sites, the hydrogen removal capacity is limited, and it is difficult to achieve a good hydrogen removal effect; if the Pt loading is too high (Example 7), the excessive platinum group metals introduce additional interfacial polarization and ohmic resistance, the voltage increases, and it is difficult to reduce hydrogen cross-permeability without significantly increasing resistance.

[0084] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A proton exchange membrane with catalytic hydrogen inhibition function, characterized in that, The proton exchange membrane with catalytic hydrogen blocking function includes a proton conductive base film layer and a first catalytic hydrogen blocking functional layer disposed on one side surface of the proton conductive base film layer, and optionally a second catalytic hydrogen blocking functional layer disposed on the other side surface of the proton conductive base film layer. The first and second catalytic hydrogen barrier functional layers each independently comprise a platinum group metal catalyst and a proton-conducting polymer. The platinum group metal catalyst loaded on the proton exchange membrane with catalytic hydrogen inhibition function is 0.001~0.1 mg / cm³. 2 .

2. The proton exchange membrane with catalytic hydrogen inhibition function according to claim 1, characterized in that, The thickness of the first catalytic hydrogen barrier functional layer and the second catalytic hydrogen barrier functional layer is independently 0.05~5 μm, more preferably 0.1~1 μm; Preferably, the loading of platinum group metal catalyst on the proton exchange membrane with catalytic hydrogen inhibition function is 0.002~0.02 mg / cm³. 2 ; Preferably, the platinum group metal catalyst comprises a platinum group metal and optionally a support; Preferably, the platinum group metals include any one or a combination of at least two of platinum, platinum alloys, palladium, palladium alloys, rhodium, or rhodium alloys. Preferably, the support comprises a carbon support and / or an inorganic oxide support.

3. The proton exchange membrane with catalytic hydrogen inhibition function according to claim 1 or 2, characterized in that, The proton-conducting ionomer includes perfluorosulfonic acid resin ionomers; Preferably, the perfluorosulfonic acid resin ionomer comprises short-side-chain perfluorosulfonic acid resin and / or long-side-chain perfluorosulfonic acid resin.

4. The proton exchange membrane with catalytic hydrogen inhibition function according to any one of claims 1 to 3, characterized in that, The proton-conductive base film layer includes a perfluorosulfonic acid type proton exchange membrane and / or an enhanced proton exchange membrane; Preferably, the thickness of the proton-conductive substrate film is 30~150 μm.

5. The proton exchange membrane with catalytic hydrogen inhibition function according to claim 4, characterized in that, The perfluorosulfonic acid type proton exchange membrane includes a short-side-chain perfluorosulfonic acid resin membrane and / or a long-side-chain perfluorosulfonic acid resin membrane. Preferably, the reinforcing structure of the enhanced proton exchange membrane comprises an aromatic polymer mesh; Preferably, the aromatic polymer mesh includes polyetheretherketone mesh and / or polyphenylene sulfide mesh.

6. A method for preparing a proton exchange membrane with catalytic hydrogen inhibition function as described in any one of claims 1 to 5, characterized in that, The preparation method includes the following steps: forming a first catalytic hydrogen blocking functional layer and optionally a second catalytic hydrogen blocking functional layer on a proton conductive base film layer to obtain the proton exchange membrane with catalytic hydrogen blocking function.

7. The preparation method according to claim 6, characterized in that, The preparation method includes the following steps: (1) Platinum group metal catalysts and proton-conducting polymers are used to prepare a catalytic hydrogen-blocking functional slurry; (2) The catalytic hydrogen barrier slurry obtained in step (1) is coated on one or both sides of the proton conductive base film layer, and then dried and heat-treated to obtain the proton exchange membrane with catalytic hydrogen barrier function. Preferably, the coating in step (2) includes any one or a combination of at least two of impregnation, casting or spraying; Preferably, the drying temperature is 40~120℃; Preferably, the drying time is 1 to 10 hours; Preferably, the temperature of the heat treatment is 50~220℃, more preferably 120~200℃; Preferably, the heat treatment time is 1 to 10 hours.

8. The preparation method according to claim 6, characterized in that, The preparation method includes the following steps: (I) Prepare a catalytic hydrogen-blocking functional slurry by combining platinum group metal precursors and proton-conducting ionomers; (II) Coat the catalytic hydrogen barrier slurry obtained in step (I) onto one or both surfaces of the proton conductive base film layer, dry and reduce it to obtain the proton exchange membrane with catalytic hydrogen barrier function. Preferably, the coating in step (II) includes any one or a combination of at least two of impregnation, casting or spraying; preferably, the reduction includes chemical reduction or electrochemical reduction.

9. A water electrolysis device, characterized in that, The water electrolysis device includes an anode chamber, a cathode chamber, and a proton exchange membrane with catalytic hydrogen inhibition function as described in any one of claims 1 to 5 disposed between the anode chamber and the cathode chamber; the first catalytic hydrogen inhibition functional layer of the proton exchange membrane with catalytic hydrogen inhibition function is located on the side closer to the anode chamber.

10. The application of a proton exchange membrane with catalytic hydrogen inhibition function as described in any one of claims 1 to 5 or a water electrolysis device as described in claim 9 in water electrolysis hydrogen production.

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