PEM electrolysis water hydrogen production membrane electrode and preparation method thereof

Abstract

This invention discloses a PEM (Polymer Electrolysis Membrane Electrode) for hydrogen production via water electrolysis and its preparation method. The method involves: firstly, adding three-dimensional interface reinforcement layers to both the anode and cathode of a proton exchange membrane (PEM); then, setting a cathode catalytic layer and an anode catalytic layer on the surface of the three-dimensional interface reinforcement layers; finally, setting a cathode gas diffusion layer and an anode gas diffusion layer on the anode and cathode catalytic layers, respectively, to obtain the membrane electrode. This invention enhances the contact interface on both sides of the anode and cathode of the PEM, which not only strengthens the PEM and reduces swelling and deformation, but also forms a three-dimensional contact interface, improving the contact between the catalytic layer and the PEM, and enhancing proton transfer between them, thus effectively improving the performance and stability of the membrane electrode. The membrane electrode of this invention effectively enhances the strength of the PEM, increases the proton conduction rate at the contact interface between the catalytic layer and the PEM, and improves the performance and stability of the membrane electrode.

Description

Technical Field

[0001] This invention relates to the field of PEM electrolysis for hydrogen production technology, and particularly to a method for preparing a PEM electrolysis membrane electrode for hydrogen production. Background Technology

[0002] Hydrogen is widely available, has a high calorific value, and produces only water as a combustion product. It is a renewable and clean energy source that will become an important part of future energy and plays a pivotal role in energy development.

[0003] Hydrogen can be produced in various ways, mainly through fossil fuel reforming, industrial by-product gas production, and water electrolysis. Water electrolysis is a green method and is expected to be the primary method for hydrogen production in the future. Among these, proton exchange membrane (PEM) water electrolysis technology offers advantages such as higher operating current density, higher electrolysis efficiency, higher hydrogen purity, higher production pressure, and faster response, making it considered the most promising hydrogen production technology. Currently, it is being gradually promoted in areas such as water electrolysis for wind and solar renewable energy, hydrogen production at hydrogen refueling stations, and hydrogen storage. In a PEM water electrolysis device, the membrane electrode assembly (MEA) is the core component of the electrolyzer, the site of the electrochemical decomposition reaction of water, and directly determines the performance and lifespan of the PEM electrolyzer.

[0004] The PEM (Polymer Electrolysis Membrane Electrode) for water electrolysis is mainly composed of a proton exchange membrane, an anode catalyst layer, a cathode catalyst layer, an anode diffusion layer, and a cathode diffusion layer. The preparation method and process of the membrane electrode have a significant impact on the performance of water electrolysis. Currently, a common method is to directly coat the anode and cathode catalyst slurries onto both sides of the proton exchange membrane using coating, transfer, or spraying methods. This method is relatively simple and easy to complete, but it is prone to causing swelling and deformation of the proton exchange membrane, which can damage the membrane's strength. Furthermore, the high interfacial impedance between the catalyst layer and the proton exchange membrane leads to high proton transport resistance, severely affecting the electrolysis performance and stability of the membrane electrode. Summary of the Invention

[0005] The main objective of this invention is to provide a method for preparing a PEM (Polymer Electrode) membrane electrode for hydrogen production via water electrolysis. This method aims to address the problems of swelling and deformation of the proton exchange membrane during existing membrane electrode preparation processes and water electrolysis, as well as the issues of high contact impedance and proton conduction resistance between the catalyst layer and the proton exchange membrane in the prepared membrane electrode. The PEM membrane electrode for hydrogen production via water electrolysis provided by this invention effectively enhances the strength of the proton exchange membrane, increases the proton conduction rate at the interface between the catalyst layer and the proton exchange membrane, and improves the performance and stability of the membrane electrode.

[0006] To achieve the above objectives, this invention proposes a method for preparing a PEM (Polymer Electrolysis Membrane) water electrolysis membrane electrode for hydrogen production, the method comprising:

[0007] a. First, add three-dimensional interface enhancement layers to both the anode and cathode of the proton exchange membrane;

[0008] b. Then, a cathode catalytic layer and an anode catalytic layer are disposed on the surface of the three-dimensional interface enhancement layer of the proton exchange membrane;

[0009] c. Finally, a cathode gas diffusion layer and an anode gas diffusion layer are set on the anode and cathode catalyst layers, and hot pressing is performed to obtain the PEM water electrolysis hydrogen production membrane electrode.

[0010] The three-dimensional interface enhancement layer comprises carbon materials and ionomers.

[0011] More preferably, the carbon material includes one or more of carbon powder, nanotubes, graphene, and carbon nanospheres.

[0012] More preferably, the ionomer comprises one or more of Nafion®, 3M PFSA, SPEEK, and SPES.

[0013] In the above method, step a includes:

[0014] A three-dimensional interface reinforcement layer slurry is sprayed onto both sides of the anode and cathode of a proton exchange membrane to obtain an interface-reinforced proton exchange membrane; wherein, the three-dimensional interface reinforcement layer comprises carbon materials and ionomers.

[0015] More preferably, the loading of carbon material and ionomer in the three-dimensional interface reinforcement layer is 0.1–1.0 mg / cm³. 2 .

[0016] More preferably, the ratio of carbon material to ionomer in the three-dimensional interface reinforcement layer is 0.2-0.8.

[0017] In the above method, step b includes:

[0018] A cathode catalytic layer slurry and an anode catalytic layer slurry are sprayed onto the surface of the anode-cathode three-dimensional interface reinforcement layer of the proton exchange membrane, respectively, and dried to obtain a cathode catalytic layer and an anode catalytic layer disposed on both sides of the proton exchange membrane containing the anode-cathode interface reinforcement layer; wherein, the cathode catalytic layer slurry includes a cathode catalyst, a binder and a dispersant, and the anode catalytic layer slurry includes an anode catalyst, a binder and a dispersant.

[0019] Further optionally, in the cathode catalyst slurry: the cathode catalyst includes one or more of Pt / C and Pt black; the binder includes a perfluorosulfonic acid resin solution; and the dispersant includes one or more of deionized water, ethanol, and isopropanol.

[0020] Further optionally, in the anode catalyst slurry: the anode catalyst includes one or more of IrO2, RuO2, and Pt black; the binder includes a perfluorosulfonic acid resin solution; and the dispersant includes one or more of deionized water, ethanol, and isopropanol.

[0021] Further optionally, the Pt loading in the cathode catalyst layer is 0.3–1.0 mg / cm³. 2 The anolyte catalyst loading in the anolyte catalyst layer is 0.5–3.0 mg / cm³. 2 .

[0022] In the above method, step c includes: setting a cathode gas diffusion layer and an anode gas diffusion layer on the anode and cathode catalyst layers, wherein the cathode gas diffusion layer and the anode gas diffusion layer are one of sintered titanium felt, titanium mesh, titanium foam, carbon cloth, and carbon paper; and then obtaining the PEM water electrolysis hydrogen production membrane electrode by hot pressing treatment.

[0023] In this invention, the membrane electrode structure is as follows: a three-dimensional interface enhancement layer is disposed on both sides of the proton exchange membrane anode and cathode; a cathode catalytic layer and an anode catalytic layer are disposed on the surface of the three-dimensional interface enhancement layer; a cathode gas diffusion layer and an anode gas diffusion layer (e.g., ...) are respectively disposed on the cathode catalytic layer and the anode catalytic layer. Figure 3 As shown in the figure), the three-dimensional interface enhancement layer is uniformly dispersed on the surface of the proton exchange membrane, and the stability of the membrane electrode is significantly improved. When the voltage is 1.9V, the current density increases by 17.3%; and after 50 hours of stability testing, the voltage change is only 6.67%, which is reduced by 21.33%.

[0024] Compared with the prior art, the advantages of the present invention are:

[0025] The technical solution provided by this invention employs a method of constructing a three-dimensional interface reinforcement layer to enhance both sides of the proton exchange membrane. During this process, the three-dimensional interface reinforcement layer can be well embedded into the surface of the proton exchange membrane, effectively enhancing the strength of the membrane and preventing swelling and deformation during membrane electrode fabrication and water electrolysis. Simultaneously, by adding a three-dimensional interface reinforcement layer to both sides of the proton exchange membrane, the contact interface between the catalyst layer and the proton exchange membrane is strengthened, contact impedance is reduced, and the proton transfer rate between the catalyst layer and the proton exchange membrane is increased, thereby improving the performance and stability of the membrane electrode and enhancing its consistency. Attached Figure Description

[0026] Figure 1 This is a cross-sectional scanning electron microscope image of the PEM water electrolysis hydrogen production membrane electrode prepared in Example 1 of the present invention;

[0027] Figure 2This is a scanning electron microscope (SEM) image of the three-dimensional interface reinforcement layer of the PEM water electrolysis hydrogen production membrane electrode prepared in Example 1 of the present invention.

[0028] Figure 3 This is a schematic diagram of a PEM water electrolysis hydrogen production membrane electrode with a three-dimensional interface enhancement layer; where 1 is the proton exchange membrane, 2 is the anode three-dimensional interface enhancement layer, 3 is the anode catalytic layer, 4 is the anode diffusion layer, 5 is the cathode three-dimensional interface enhancement layer, 6 is the cathode catalytic layer, and 7 is the cathode diffusion layer.

[0029] Figure 4 The results are the performance test results of the PEM water electrolysis hydrogen production membrane electrodes prepared in Examples 1, 2 and Comparative Example 1 of this invention.

[0030] Figure 5 The results show the stability test results of the PEM water electrolysis hydrogen production membrane electrodes prepared in Examples 1, 2 and Comparative Example 1 of this invention. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0032] It should be noted that the terms "comprising" and "having," and any variations thereof, in the embodiments and drawings of this specification are intended to cover non-exclusive inclusion. For example, it may include a series of materials, not limited to the materials listed, but optionally including materials not listed, or optionally including other materials inherent to these materials.

[0033] The PEM (Polymer Electrolysis Membrane Electrode) for water electrolysis is mainly composed of a proton exchange membrane, an anode catalyst layer, a cathode catalyst layer, an anode diffusion layer, and a cathode diffusion layer. The preparation method and process of the membrane electrode have a significant impact on the performance of water electrolysis. Currently, a common method is to directly coat the anode and cathode catalyst slurries onto both sides of the proton exchange membrane using coating, transfer, or spraying methods. This method is relatively simple and easy to complete, but it is prone to causing swelling and deformation of the proton exchange membrane, which can damage the membrane's strength. Furthermore, the high interfacial impedance between the catalyst layer and the proton exchange membrane leads to high proton transport resistance, severely affecting the electrolysis performance and stability of the membrane electrode.

[0034] In view of this, the present invention proposes a method for preparing a PEM electrolysis water-to-hydrogen membrane electrode. In this embodiment, the method for preparing the PEM electrolysis water-to-hydrogen membrane electrode includes the following steps:

[0035] Step a: The three-dimensional interface reinforcement layer slurry is sprayed onto both sides of the anode and cathode of the proton exchange membrane to obtain an interface-reinforced proton exchange membrane; wherein the three-dimensional interface reinforcement layer comprises carbon materials and ionomers.

[0036] The present invention does not limit the specific types of carbon materials. In this embodiment, the carbon materials include one or more of carbon powder, carbon nanotubes, graphene and carbon nanospheres; the ionomers include one or more of Nafion®, 3M PFSA, SPEEK and SPES.

[0037] Step b: A cathode catalytic layer and an anode catalytic layer are respectively disposed on the surface of the anode-cathode three-dimensional interface enhancement layer of the proton exchange membrane;

[0038] In one specific embodiment, step b includes: spraying cathode catalyst layer slurry and anode catalyst layer slurry onto the surface of the anode-cathode three-dimensional interface enhancement layer of the proton exchange membrane, respectively, and drying them to obtain cathode catalyst layer and anode catalyst layer disposed on both sides of the proton exchange membrane containing the anode-cathode interface enhancement layer;

[0039] The cathode catalyst slurry comprises a cathode catalyst, a binder, and a dispersant. In one embodiment, the cathode catalyst comprises one or more of Pt / C and Pt black; the binder comprises a perfluorosulfonic acid resin solution; and the dispersant comprises one or more of deionized water, ethanol, and isopropanol.

[0040] Furthermore, the cathode catalyst loading in the cathode catalyst layer is 0.3–1.0 mg / cm³. 2 The mass of perfluorosulfonic acid resin in the perfluorosulfonic acid resin solution is 20-30% of the mass of the cathode catalyst.

[0041] The anode catalyst slurry includes an anode catalyst, a binder, and a dispersant. In one embodiment, the anode catalyst includes one or more of IrO2, RuO2, and Pt black; the binder includes a perfluorosulfonic acid resin solution; and the dispersant includes one or more of deionized water, ethanol, and isopropanol.

[0042] Furthermore, the anolyte catalyst loading in the anolyte catalyst layer is 0.5–3.0 mg / cm³. 2 The mass of perfluorosulfonic acid resin in the perfluorosulfonic acid resin solution is 20-30% of the mass of the cathode catalyst.

[0043] Step c: A cathode gas diffusion layer and an anode gas diffusion layer are disposed on the anode and cathode catalyst layers. In one embodiment, the cathode gas diffusion layer and the anode gas diffusion layer are one of sintered titanium felt, titanium mesh, titanium foam, carbon cloth, and carbon paper; then, through hot pressing treatment, the PEM water electrolysis hydrogen production membrane electrode is obtained.

[0044] Furthermore, the thickness of the anode and cathode gas diffusion layers is 0.1-0.6 mm.

[0045] Furthermore, the preparation methods for the anode-cathode interface reinforcement layer and the anode-cathode catalyst layer can be any one of coating, transfer printing, or spraying. The preparation order of the anode-cathode interface three-dimensional reinforcement layer and the anode-cathode catalyst layer is not limited, and both sides can be prepared simultaneously.

[0046] In this invention, a schematic diagram of the PEM water electrolysis hydrogen production membrane electrode with a three-dimensional interface enhancement layer is shown below. Figure 3 As shown, 1 is a proton exchange membrane with an anode three-dimensional interface enhancement layer 2 and a cathode three-dimensional interface enhancement layer 5 respectively disposed on both sides. The cathode three-dimensional interface enhancement layer 5 is provided with a cathode catalytic layer 6; the anode three-dimensional interface enhancement layer 2 is provided with an anode catalytic layer 3; the cathode catalytic layer 6 is provided with a cathode diffusion layer 7; and the anode catalytic layer 3 is provided with an anode diffusion layer 4.

[0047] The technical solution provided by this invention employs a method of constructing a three-dimensional interface reinforcement layer to enhance both sides of the proton exchange membrane. During this process, the three-dimensional interface reinforcement layer can be well embedded into the surface of the proton exchange membrane, effectively enhancing the strength of the membrane and preventing swelling and deformation during membrane electrode fabrication and water electrolysis. Simultaneously, by adding a three-dimensional interface reinforcement layer to both sides of the proton exchange membrane, the contact interface between the catalyst layer and the proton exchange membrane is strengthened, contact impedance is reduced, and the proton transfer rate between the catalyst layer and the proton exchange membrane is increased, thereby improving the performance and stability of the membrane electrode and enhancing its consistency.

[0048] This invention, through the method of constructing a three-dimensional interface reinforcement layer on both sides of a proton exchange membrane, effectively improves the performance and stability of the PEM water electrolysis hydrogen production membrane electrode, and also increases the yield of the membrane electrode. Furthermore, the process employed in this invention is simple, has low production costs, and enables large-scale production of the membrane electrode.

[0049] The technical solution of the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. It should be understood that the following embodiments are only used to explain the present invention and do not limit the present invention.

[0050] Example 1

[0051] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0052] (2) Carbon nanotubes were directly dispersed into a 5% Nafion ethanol solution by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dried Nafion was 1:1, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0053] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0054] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0055] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0056] Example 2

[0057] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0058] (2) Carbon nanotubes were directly dispersed into an ethanol solution of 3M PFSA by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dried 3M PFSA was 1:1, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0059] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0060] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0061] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0062] Example 3

[0063] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0064] (2) Carbon nanotubes were directly dispersed into an ethanol solution of sulfonated polyether ether ketone (SPEEK) by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active regions of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dry SPEEK was 1:1, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0065] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0066] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0067] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0068] Example 4

[0069] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0070] (2) Graphene was directly dispersed into a 5% Nafion ethanol solution by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of graphene to dry Nafion was 1:1, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0071] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0072] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0073] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0074] Example 5

[0075] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0076] (2) Carbon nanotubes were directly dispersed into a 5% Nafion ethanol solution by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dried Nafion was 1:1, and the loading of the three-dimensional interface reinforcement layer was 0.8 mg / cm³. 2 ;

[0077] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0078] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0079] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0080] Example 6

[0081] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0082] (2) Carbon nanotubes were directly dispersed into a 5% Nafion ethanol solution by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dried Nafion was 2:1, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0083] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0084] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0085] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0086] Example 7

[0087] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0088] (2) Carbon nanotubes were directly dispersed into a 5% Nafion ethanol solution by ultrasonication to form a three-dimensional interface reinforcement layer slurry. The slurry was then sprayed onto the active areas of the anode and cathode sides of the pretreated proton exchange membrane using an ultrasonic spraying device and dried. The ratio of carbon nanotubes to dried Nafion was 1:2, and the loading of the three-dimensional interface reinforcement layer was 0.4 mg / cm³. 2 ;

[0089] (3) A cathode catalyst slurry is formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading is 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0090] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane with a three-dimensional interface reinforcement layer using an ultrasonic spraying device.

[0091] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0092] Comparative Example 1

[0093] (1) Cut a 40×40mm DuPont Nafion 117 proton exchange membrane and soak it in 5% H2O2 solution, 0.5M H2SO4 solution and deionized water at 80℃ for 1 hour. Then soak the membrane in deionized water for later use. Before use, dry the proton exchange membrane. The active area is 30×30mm.

[0094] (2) A cathode catalyst slurry was formed by uniformly dispersing an ethanol solution of 60% Pt / C and 5% Nafion in isopropanol, wherein the Pt loading was 0.5 mg / cm³. 2 The dry Nafion mass is 60% and the Pt / C catalyst mass is 25%. The cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane using an ultrasonic spraying device.

[0095] (4) The ethanol solution of 5% Nafion and the anolyte catalyst IrO2 is uniformly dispersed in isopropanol to form an anolyte catalyst slurry, wherein the IrO2 loading is 2 mg / cm³. 2 The dry Nafion mass is 25% of the IrO2 catalyst mass. The cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane using an ultrasonic spraying device.

[0096] (5) Cut two 30×30mm sintered titanium felts, soak them in ethanol, ultrasonically clean them for 1 hour, dry them and place them on the surface of the anode and cathode catalyst layers respectively. Then, press the sintered titanium felts to the anode and cathode catalyst layers to form a gas diffusion layer. At the same time, PEM water electrolysis hydrogen production membrane electrode is prepared. The thickness of the sintered titanium felt is 0.6mm.

[0097] Structural characterization:

[0098] The PEM water electrolysis hydrogen production membrane electrode prepared in Example 1 was characterized under a scanning electron microscope, and the results are as follows: Figure 1 , Figure 2 As shown. Figure 1 The image shows a cross-sectional electron microscope image of the membrane electrode, clearly revealing the three-dimensional interface reinforcement layer between the proton exchange membrane and the catalyst layer. Figure 2 The image shows a surface electron microscope image of the three-dimensional interface enhancement layer. The results show that CNTs and Nafion are uniformly dispersed on the surface of the proton exchange membrane.

[0099] Performance testing

[0100] The membrane electrodes prepared in Examples 1, 2, 3, 4, and Comparative Example 1 were assembled into a PEM water electrolysis testing system for polarization performance testing. The results are as follows: Figure 4 As shown. During the membrane electrode stability test, the current density was set to 1.6 A / cm. 2 A 50-hour stability test was conducted, and the results were as follows: Figure 5 As shown. The test temperature was 70℃, and the active area of ​​the test membrane electrode was 9 cm². 2 .

[0101] Depend on Figure 4 It can be seen that when the voltage is 1.9V, the membrane electrode current density in Example 1 is 2.08A / cm². 2 The membrane electrode current density in Example 2 was 1.91 A / cm². 2 The membrane electrode current density in Example 3 was 1.98 A / cm². 2 The membrane electrode current density in Example 4 was 1.88 A / cm². 2 The membrane electrode current density in Comparative Example 1 is 1.72 A / cm². 2The results showed that the performance of the membrane electrodes was significantly improved after adding a three-dimensional interface reinforcement layer.

[0102] Depend on Figure 5 As can be seen, the initial voltage of the membrane electrode in Example 1 was 1.8V, and after 50 hours of stability testing, the voltage increased to 1.92V, with a voltage change of only 6.67%; the initial voltage of the membrane electrode in Example 2 was 1.84V, and after 50 hours of stability testing, the voltage increased to 1.98V, with a voltage change of 7.61%; the initial voltage of the membrane electrode in Example 3 was 1.84V, and after 50 hours of stability testing, the voltage increased to 1.96V, with a voltage change of 7.10%; the initial voltage of the membrane electrode in Example 4 was 1.85V, and after 50 hours of stability testing, the voltage increased to 2.17V, with a voltage change of 17.29%; the initial voltage of the membrane electrode in Comparative Example 1 was 1.89V, and after 50 hours of stability testing, the voltage increased to 2.42V, with a voltage change of 28.04%. This demonstrates that adding a three-dimensional interface enhancement layer to both sides of the proton exchange membrane significantly improves the stability of the membrane electrode, especially the scheme in Example 1, where both membrane electrode performance and stability are significantly improved.

[0103] In this application, the carbon material in the three-dimensional interface reinforcement layer has a certain three-dimensional structure. Its main function is to construct the three-dimensional contact surface between the catalyst layer and the proton exchange membrane, reducing the contact impedance between the membrane electrode catalytic layer and the proton exchange membrane. Simultaneously, the strength of the carbon material enhances the surface strength of the proton exchange membrane, preventing swelling and deformation during water electrolysis. The ionomers in the three-dimensional interface reinforcement layer primarily act as adhesives to the carbon material, ensuring a stable bond between the carbon material and the proton exchange membrane surface, while also maintaining the proton conductivity between the three-dimensional interface reinforcement layer, the proton exchange membrane, and the catalyst layer.

[0104] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A method for preparing a PEM electrolysis water-splitting membrane electrode, characterized by, The method comprises the following steps: a. Adding three-dimensional interface enhancement layers on both sides of the proton exchange membrane anode and cathode respectively; b. Setting a cathode catalyst layer and an anode catalyst layer on the surface of the three-dimensional interface enhancement layers of the proton exchange membrane anode and cathode; c. Setting a cathode gas diffusion layer and an anode gas diffusion layer on the cathode catalyst layer and the anode catalyst layer, and performing heat pressing treatment to obtain a PEM water electrolysis hydrogen membrane electrode; The three-dimensional interface enhancement layer comprises carbon material and ionomer; The carbon material comprises one or more of carbon powder, carbon nanotube, graphene and carbon nanosphere; The ionomer comprises Nafion, 3M PFSA or SPEEK; The total loading of the three-dimensional interfacial reinforcement layer carbon material and ionomer is 0.1-1.0 mg / cm 2 ; The mass ratio of the carbon material and the ionomer of the three-dimensional interface enhancement layer is 1:2-2:1; Step a is specifically: spraying three-dimensional interface enhancement layer slurry to both sides of the proton exchange membrane anode and cathode respectively, so that the three-dimensional interface enhancement layer is uniformly dispersed on the surface of the proton exchange membrane, to obtain an interface-enhanced proton exchange membrane.

2. The method for preparing the PEM electrolysis water-to-hydrogen membrane electrode as described in claim 1, characterized in that, Step b comprises: spraying a cathode catalyst layer slurry and an anode catalyst layer slurry on the surface of the three-dimensional interface enhancement layers of the proton exchange membrane anode and cathode respectively, and drying to obtain a cathode catalyst layer and an anode catalyst layer arranged on both sides of the proton exchange membrane containing the three-dimensional interface enhancement layers of the anode and the cathode; The cathode catalyst layer slurry comprises a cathode catalyst, a binder and a dispersant; The anode catalyst layer slurry comprises an anode catalyst, a binder and a dispersant.

3. The method for preparing the PEM electrolysis water-to-hydrogen membrane electrode as described in claim 2, characterized in that, The cathode catalyst slurry comprises one or more of Pt / C and Pt black; The binder comprises a perfluorosulfonic acid resin solution; The dispersant comprises one or more of deionized water, ethanol and isopropanol; The anode catalyst comprises one or more of IrO2, RuO2 and Pt black; The binder comprises a perfluorosulfonic acid resin solution; The dispersant comprises one or more of deionized water, ethanol and isopropanol; Step c comprises: setting a cathode gas diffusion layer and an anode gas diffusion layer on the cathode catalyst layer and the anode catalyst layer, wherein the cathode gas diffusion layer and the anode gas diffusion layer are one of sintered titanium felt, titanium mesh, titanium foam, carbon cloth and carbon paper; and then performing heat pressing treatment to obtain a PEM water electrolysis hydrogen membrane electrode with the cathode gas diffusion layer and the anode gas diffusion layer arranged on both sides of the cathode catalyst layer and the anode catalyst layer. The Pt loading in the cathode catalytic layer is 0.3-1.0 mg / cm 2 ; The anode catalyst loading in the anode catalytic layer is 0.5-3.0 mg / cm 2 .

4. The PEM electrolytic water hydrogen producing membrane electrode and the method of making the same according to claim 1, wherein, The structure of the membrane electrode is that three-dimensional interface enhancement layers are arranged on both sides of the proton exchange membrane anode and cathode, the surface of the three-dimensional interface enhancement layers is provided with a cathode catalyst layer and an anode catalyst layer, the cathode catalyst layer and the anode catalyst layer are respectively provided with a cathode gas diffusion layer and an anode gas diffusion layer, the three-dimensional interface enhancement layers are uniformly dispersed on the surface of the proton exchange membrane, and the stability of the membrane electrode is obviously improved, wherein the current density is increased by 17.3% when the voltage is 1.9 V, and the voltage change is only 6.67% after 50 hours of stability test, which is reduced by 21.33%.

5. A PEM water electrolysis hydrogen producing membrane electrode produced by the method of any one of claims 1 to 4, characterized in that, ​

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