CN116254559A - PEM (PEM) electrolytic water hydrogen production membrane electrode and preparation method thereof - Google Patents

Abstract

The invention discloses a PEM electrolyzed water hydrogen production membrane electrode and a preparation method thereof. The method is as follows: firstly add a three-dimensional interface enhancement layer on both sides of the cathode and anode of the proton exchange membrane respectively; then install a cathode catalyst layer and an anode catalyst layer on the surface of the cathode and anode three-dimensional interface enhancement layer; finally install a cathode gas diffusion layer on the cathode and anode catalyst layers respectively. layer and the anode gas diffusion layer to obtain a membrane electrode. The invention enhances the contact interface on both sides of the cathode and anode of the proton exchange membrane, which can not only enhance the strength of the proton exchange membrane, reduce the swelling and deformation of the proton exchange membrane, but also form a three-dimensional contact interface to improve the catalytic layer and proton contact interface. The contact between the exchange membranes improves the transfer of protons between the catalytic layer and the proton exchange membrane, effectively improving the performance and stability of the membrane electrode. The membrane electrode of the invention can effectively enhance the strength of the proton exchange membrane, increase the conduction rate of protons at the contact interface between the catalytic layer and the proton exchange membrane, and improve the performance and stability of the membrane electrode.

Description

A kind of PEM electrolysis water hydrogen production film electrode and preparation method thereof

technical field

The invention relates to the technical field of hydrogen production by PEM electrolysis of water, in particular to a preparation method of a hydrogen production membrane electrode by PEM electrolysis of water.

Background technique

Hydrogen has a wide range of sources, a high combustion calorific value, and only water as a combustion product. It is a renewable and clean energy that will become an important part of future energy and play a pivotal role in energy development.

There are various ways to produce hydrogen, mainly including hydrogen production from fossil energy reforming, hydrogen production from industrial by-product gas, and hydrogen production from electrolyzed water. Hydrogen production from electrolyzed water is a green way to produce hydrogen, and it will also be the way to produce hydrogen in the future. Main way. Among them, proton exchange membrane (PEM) electrolysis water hydrogen production technology has the advantages of higher working current density, high electrolysis efficiency, high hydrogen production purity, high hydrogen production pressure and fast response, and is considered to be the most promising hydrogen production technology. . At present, it is being gradually promoted in the fields of photovoltaic renewable energy electrolysis water hydrogen production, hydrogen refueling station hydrogen production, hydrogen energy storage and other fields. In the PEM water electrolysis device, the membrane electrode is the core component of the electrolyzer and the place where the electrochemical decomposition reaction of water occurs, directly determining the performance and life of the PEM electrolyzer.

The PEM electrolytic water membrane electrode is mainly composed of a proton exchange membrane, an anode catalytic layer, a cathode catalytic layer, an anode diffusion layer, and a cathode diffusion layer. The preparation method and process of the membrane electrode have a great influence on the performance of electrolyzed water. At present, the commonly used method is to directly cover the cathode and anode catalyst layer slurry on both sides of the proton exchange membrane by coating, transfer printing or spraying. The process of the method is relatively simple, and it is easy to complete the preparation of the membrane electrode, but it is easy to cause swelling and deformation of the proton exchange membrane, which will damage the strength of the membrane to a certain extent. At the same time, the direct contact interface impedance between the catalytic layer and the proton exchange membrane is large, resulting in The transmission resistance of the membrane electrode is large, which seriously affects the electrolytic performance and stability of the membrane electrode.

Contents of the invention

The main purpose of the present invention is to propose a method for preparing a PEM electrolyzed water hydrogen production membrane electrode. It aims to solve the problem that the proton exchange membrane is prone to swelling and deformation in the existing membrane electrode preparation process and the water electrolysis process, and at the same time solve the problems of large contact resistance and proton conduction resistance between the prepared membrane electrode catalytic layer and the proton exchange membrane. question. The PEM hydrogen production membrane electrode obtained by the preparation method provided by the invention can effectively enhance the strength of the proton exchange membrane, increase the conduction rate of protons at the contact interface between the catalytic layer and the proton exchange membrane, and improve the performance and stability of the membrane electrode.

In order to achieve the above object, the present invention proposes a method for preparing a PEM electrolyzed water hydrogen production membrane electrode, the preparation method comprising:

a. First, add a three-dimensional interface enhancement layer on both sides of the cathode and anode of the proton exchange membrane;

b. set the cathode catalyst layer and the anode catalyst layer on the surface of the cathode and anode three-dimensional interface enhancement layer of the proton exchange membrane;

c. Finally, a cathode gas diffusion layer and an anode gas diffusion layer are set on the cathode and anode catalyst layers, and hot-pressed to obtain a PEM electrolyzed water hydrogen production membrane electrode;

Wherein, the three-dimensional interface enhancement layer includes carbon material and ionomer.

Further preferably, the carbon material includes one or more of carbon powder, nanotubes, graphene and carbon nanospheres.

Further preferably, the ionomer comprises one or more of Nafion®, 3M PFSA, SPEEK, and SPES.

In the above method, step a includes:

The slurry of the three-dimensional interface enhancement layer is sprayed on both sides of the cathode and anode of the proton exchange membrane respectively to obtain the interface-enhanced proton exchange membrane; wherein, the three-dimensional interface enhancement layer contains carbon materials and ionomers.

Further preferably, the loading of the carbon material and ionomer in the three-dimensional interface enhancing layer is 0.1-1.0 mg/cm ² .

Further preferably, the ratio of the carbon material to the ionomer in the three-dimensional interface enhancement layer is 0.2-0.8.

In the above method, step b includes:

Spray the cathode catalyst layer slurry and the anode catalyst layer slurry on the surface of the negative and anode three-dimensional interface enhancement layer of the proton exchange membrane respectively, and dry to obtain the cathode catalyst layer and the cathode catalyst layer arranged on both sides of the proton exchange membrane containing the cathode and anode interface enhancement layer. An anode catalyst layer; wherein, the cathode catalyst layer slurry includes a cathode catalyst, a binder and a dispersant, and the anode catalyst layer slurry includes an anode catalyst, a binder and a dispersant.

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; the dispersant includes One or more of deionized water, ethanol, and isopropanol.

Further optionally, in the anode catalyst slurry: the anode catalyst includes one or more of IrO ₂ , RuO ₂ , and Pt black; the binder includes a perfluorosulfonic acid resin solution; the dispersed Agents include one or more of deionized water, ethanol, and isopropanol.

Further optionally, 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 .

In the above method, step c includes: setting a cathode gas diffusion layer and an anode gas diffusion layer on the cathode and anode catalytic layers, and the cathode gas diffusion layer and the anode gas diffusion layer are made of sintered titanium felt, titanium mesh, foamed titanium, carbon One of cloth and carbon paper; and then through hot-pressing treatment, the PEM electrolysis water hydrogen production membrane electrode is obtained.

In the present invention, the structure of the membrane electrode is as follows: a three-dimensional interface enhancement layer is arranged on both sides of the cathode and anode of the proton exchange membrane, and the surface of the three-dimensional interface enhancement layer is provided with a cathode catalyst layer and an anode catalyst layer; A cathode gas diffusion layer and an anode gas diffusion layer are respectively arranged on the catalytic layer (as shown in Figure 3); the three-dimensional interface enhancement layer is evenly dispersed on the surface of the proton exchange membrane, and the stability of the membrane electrode is significantly improved , where when the voltage was 1.9V, the current density increased by 17.3%; after a 50-hour stability test, the voltage change was only 6.67%, a decrease of 21.33%.

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

In the technical solution provided by the present invention, the two sides of the proton exchange membrane are enhanced by the method of constructing a three-dimensional interface enhancement layer. During this process, the three-dimensional interface enhancement layer can be well embedded in the surface layer of the proton exchange membrane, which can effectively enhance The strength of the exchange membrane prevents the swelling and deformation of the membrane during the preparation of the membrane electrode and the electrolysis of water. At the same time, by adding a three-dimensional interface enhancement layer on both sides of the proton exchange membrane, the contact interface between the catalytic layer and the proton exchange membrane can be enhanced, the contact resistance can be reduced, and the transfer rate of protons between the catalytic layer and the proton exchange membrane can be increased, thereby improving the membrane electrode. Performance and stability, improve the consistency of membrane electrodes.

Description of drawings

Fig. 1 is the cross-sectional scanning electron micrograph of the PEM electrolyzed water hydrogen production membrane electrode that the embodiment of the present invention 1 makes;

Fig. 2 is the surface scanning electron micrograph of the three-dimensional interface enhancing layer of the PEM electrolyzed water hydrogen production membrane electrode that the embodiment 1 of the present invention makes;

Figure 3 is a schematic diagram of a PEM electrolytic water hydrogen production membrane electrode with a three-dimensional interface enhancement layer; 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, and 5 is the cathode three-dimensional interface Reinforcing layer, 6 is the cathode catalytic layer, and 7 is the cathode diffusion layer;

Fig. 4 is the performance test result of the PEM electrolyzed water hydrogen production membrane electrode that the embodiment 1 of the present invention, embodiment 2 and comparative example 1 make;

Fig. 5 shows the stability test results of the PEM electrolyzed water hydrogen production membrane electrodes prepared in Example 1, Example 2 and Comparative Example 1 of the present invention.

Detailed ways

In order to make the purpose, 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. Those who do not indicate the specific conditions in the examples are carried out according to the conventional conditions or the conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all conventional products that could be purchased from the market.

It should be noted that the terms "include" and "have" in the embodiments of this specification and the drawings, as well as any variations thereof, are intended to cover non-exclusive inclusion. For example, a range of materials is included, not limited to those listed, but optionally also includes materials not listed, or optionally other materials inherent to these materials.

The PEM electrolytic water membrane electrode is mainly composed of a proton exchange membrane, an anode catalytic layer, a cathode catalytic layer, an anode diffusion layer, and a cathode diffusion layer. The preparation method and process of the membrane electrode have a great influence on the performance of electrolyzed water. At present, the commonly used method is to directly cover the cathode and anode catalyst layer slurry on both sides of the proton exchange membrane by coating, transfer printing or spraying. The process of the method is relatively simple, and it is easy to complete the preparation of the membrane electrode, but it is easy to cause swelling and deformation of the proton exchange membrane, which will damage the strength of the membrane to a certain extent. At the same time, the direct contact interface impedance between the catalytic layer and the proton exchange membrane is large, resulting in The transmission resistance of the membrane electrode is large, which seriously affects the electrolytic performance and stability of the membrane electrode.

In view of this, the present invention proposes a method for preparing a membrane electrode for hydrogen production by PEM electrolysis of water. In this embodiment, the method for preparing a membrane electrode for hydrogen production by PEM electrolysis of water includes the following steps:

In step a, the slurry of the three-dimensional interface enhancement layer is sprayed on both sides of the anode and cathode of the proton exchange membrane to obtain an interface-enhanced proton exchange membrane; wherein, the three-dimensional interface enhancement layer contains carbon materials and ionomers.

For the specific type of carbon material, the present invention is not limited. In this embodiment, the carbon material includes one or more of carbon powder, carbon nanotubes, graphene and carbon nanospheres; the ionomer contains One or more of Nafion®, 3M PFSA, SPEEK, SPES.

In step b, a cathode catalytic layer and an anode catalytic layer are respectively arranged on the surface of the cathode-anode three-dimensional interface enhancement layer of the proton exchange membrane;

In a specific embodiment, step b includes: spraying the slurry of the cathode catalytic layer and the slurry of the anode catalyst layer on the surface of the cathode and anode three-dimensional interface enhancement layer of the proton exchange membrane, and drying to obtain the interface enhancement layer containing the cathode and anode The cathode catalytic layer and the anode catalytic layer on both sides of the proton exchange membrane;

Wherein, the cathode catalyst layer slurry includes a cathode catalyst, a binder and a dispersant. In one embodiment, the cathode catalyst includes one or more of Pt/C and Pt black; the binder includes a perfluorosulfonic acid resin solution; the dispersant includes deionized water, ethanol, iso One or more of propanol.

Further, the cathode catalyst loading in the cathode catalyst layer is 0.3-1.0 mg/cm ² , and the mass of the perfluorosulfonic acid resin in the perfluorosulfonic acid resin solution is 20-30% of the mass of the cathode catalyst.

The anode catalyst layer slurry includes an anode catalyst, a binder and a dispersant. In one embodiment, the anode catalyst includes one or more of IrO ₂ , RuO ₂ , and Pt black; the binder includes a perfluorosulfonic acid resin solution; the dispersant includes deionized water, ethanol , one or more of isopropanol.

Further, the anode catalyst loading in the anode catalyst layer is 0.5-3.0 mg/cm ² , and the mass of the perfluorosulfonic acid resin in the perfluorosulfonic acid resin solution is 20-30% of the mass of the cathode catalyst.

Step c: setting a cathode gas diffusion layer and an anode gas diffusion layer on the cathode and anode catalytic layers. In one embodiment, the cathode gas diffusion layer and the anode gas diffusion layer are one of sintered titanium felt, titanium mesh, foamed titanium, carbon cloth, and carbon paper; Hydrogen membrane electrode.

Further, the thickness of the anode and cathode gas diffusion layers is 0.1-0.6 mm.

In addition, the preparation method of the cathode-anode interface enhancement layer and the cathode-anode catalytic layer is any one of coating, transfer printing and spray coating. Wherein, the preparation sequence of the three-dimensional reinforcement layer at the cathode-anode interface and the cathode-anode catalytic layer is not limited, and can also be performed simultaneously on both sides.

In the present invention, the structural schematic diagram of the PEM electrolytic water hydrogen production membrane electrode with a three-dimensional interface enhancement layer is shown in Figure 3, 1 is that the two sides of the proton exchange membrane are respectively provided with an anode three-dimensional interface enhancement layer 2 and a cathode three-dimensional interface enhancement layer 5 , the surface of the cathode three-dimensional interface enhancement layer 5 is provided with a cathode catalyst layer 6; the surface of the anode three-dimensional interface enhancement layer 2 is provided with an anode catalyst layer 3; the surface of the cathode catalyst layer 6 is provided with a cathode diffusion layer 7; An anode diffusion layer 4 is provided on the surface of the anode catalyst layer 3 .

In the technical solution provided by the present invention, the two sides of the proton exchange membrane are enhanced by the method of constructing a three-dimensional interface enhancement layer. During this process, the three-dimensional interface enhancement layer can be well embedded in the surface layer of the proton exchange membrane, which can effectively enhance The strength of the exchange membrane prevents the swelling and deformation of the membrane during the preparation of the membrane electrode and the electrolysis of water. At the same time, by adding a three-dimensional interface enhancement layer on both sides of the proton exchange membrane, the contact interface between the catalytic layer and the proton exchange membrane can be enhanced, the contact resistance can be reduced, and the transfer rate of protons between the catalytic layer and the proton exchange membrane can be increased, thereby improving the membrane electrode. Performance and stability, improve the consistency of membrane electrodes.

The invention can effectively improve the performance and stability of the PEM electrolyzed water hydrogen production membrane electrode through the method of constructing a three-dimensional interface enhancement layer on both sides of the proton exchange membrane, and improve the yield rate of the membrane electrode. In addition, the technology adopted in this aspect is simple, the production cost is low, and the large-scale production of membrane electrodes can be realized.

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

Example 1

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of 5% Nafion by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry to the active area of the pretreated proton exchange membrane cathode and anode side by ultrasonic spraying equipment Inside, drying; the ratio of carbon nanotubes and dry Nafion is 1:1, and the load of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 2

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of 3M PFSA by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry into the active area on the cathode and anode sides of the pretreated proton exchange membrane through ultrasonic spraying equipment , drying; the ratio of carbon nanotubes and dry 3M PFSA is 1:1, and the load of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 3

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of sulfonated polyetheretherketone (SPEEK) by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry onto the pretreated proton exchange membrane by ultrasonic spraying equipment In the active area on the cathode and anode sides, dry; the ratio of carbon nanotubes to dry SPEEK is 1:1, and the loading capacity of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 4

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse graphene directly into a 5% Nafion ethanol solution by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry into the active area of the pretreated proton exchange membrane cathode and anode sides through ultrasonic spraying equipment , drying; the ratio of graphene and dry Nafion is 1:1, and the loading capacity of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 5

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of 5% Nafion by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry to the active area of the pretreated proton exchange membrane cathode and anode side by ultrasonic spraying equipment Inside, drying; the ratio of carbon nanotubes and dry Nafion is 1:1, and the load of the three-dimensional interface enhancement layer is 0.8mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 6

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of 5% Nafion by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry to the active area of the pretreated proton exchange membrane cathode and anode side by ultrasonic spraying equipment Inside, drying; the ratio of carbon nanotubes and dry Nafion is 2:1, and the load of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Example 7

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Disperse the carbon nanotubes directly into the ethanol solution of 5% Nafion by ultrasonic to form a three-dimensional interface enhancement layer slurry, and then spray the slurry to the active area of the pretreated proton exchange membrane cathode and anode side by ultrasonic spraying equipment Inside, drying; the ratio of carbon nanotubes and dry Nafion is 1:2, and the load of the three-dimensional interface enhancement layer is 0.4mg/cm ² ;

(3) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the /C catalyst quality, the cathode catalyst slurry is sprayed to the cathode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane provided with a three-dimensional interface enhancement layer by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Comparative example 1

(1) Cut a 40×40mm DuPont Nafion117 proton exchange membrane, soak it with 5% H ₂ O ₂ solution, 0.5M H ₂ SO ₄ solution, and deionized water at 80°C for 1 hour, and then soak the membrane Prepare in deionized water, dry the proton exchange membrane before use, the active area is 30×30mm;

(2) Evenly disperse the ethanol solution of 60% Pt/C and 5% Nafion as the cathode catalyst in isopropanol to form a cathode catalyst slurry, in which the Pt loading is 0.5 mg/cm ² and the dry Nafion mass is 60% Pt 25% of the mass of /C catalyst, the cathode catalyst slurry is sprayed onto the cathode side of the proton exchange membrane by ultrasonic spraying equipment;

(4) Evenly disperse the anode catalyst IrO ₂ and 5% Nafion ethanol solution in isopropanol to form an anode catalyst slurry, in which the IrO ₂ loading is 2 mg/cm ² , and the dry Nafion mass is 25% of the IrO ₂ catalyst mass %, the cathode catalyst slurry is sprayed onto the anode side of the proton exchange membrane by ultrasonic spraying equipment;

(5) Cut two pieces of 30×30mm sintered titanium felt, soak them in ethanol, and ultrasonically clean them for 1 hour. The extremely catalytic layer is laminated to form a gas diffusion layer, and at the same time, a PEM electrolysis water hydrogen production membrane electrode is prepared; the thickness of the sintered titanium felt is 0.6mm.

Structure Characterization:

Structural characterization of the PEM electrolyzed water hydrogen production membrane electrode prepared in Example 1 was carried out under a scanning electron microscope, and the results are shown in Fig. 1 and Fig. 2 . Figure 1 is a cross-sectional electron microscope image of the membrane electrode, and the three-dimensional interface enhancement layer between the proton exchange membrane and the catalytic layer can be clearly seen; Figure 2 is the surface electron microscope image of the three-dimensional interface enhancement layer, from the results it can be seen that CNT and Nafion is uniformly dispersed on the surface of the proton exchange membrane.

Performance Testing

The membrane electrodes prepared in Example 1, Example 2, Example 3, Example 4 and Comparative Example 1 were assembled into a PEM electrolyzed water testing system for polarization performance testing, and the results are shown in FIG. 4 . During the stability test of the membrane electrode, the current density was set to 1.6A/cm ² , and the stability test was carried out for 50 hours. The results are shown in FIG. 5 . The test temperature is 70°C, and the active area of the test membrane electrode is 9cm ² .

It can be seen from Figure 4 that when the voltage is 1.9V, the current density of the membrane electrode in Example 1 is 2.08A/cm ² , the current density of the membrane electrode in Example 2 is 1.91A/cm ² , and the membrane electrode in Example 3 The current density is 1.98A/cm ² , the membrane electrode current density of Example 4 is 1.88A/cm ² , and the membrane electrode current density of Comparative Example 1 is 1.72A/cm ² . Through the comparison of the results, it is found that the performance of the membrane electrode has been greatly improved after adding a three-dimensional interface enhancement layer.

It can be seen from Figure 5 that the initial voltage of the membrane electrode in Example 1 is 1.8V, and after 50 hours of stability testing, the voltage rises to 1.92V, and the voltage change is only 6.67%; The initial voltage is 1.84V, after 50 hours of stability test, the voltage rises to 1.98V, and the voltage change is 7.61%; the membrane electrode initial voltage of embodiment 3 is 1.84V, after 50 hours of stability test, The voltage increase was 1.96V, and the voltage change was 7.10%; the initial voltage of the membrane electrode in Example 4 was 1.85V, and after 50 hours of stability testing, the voltage increase was 2.17V, and the voltage change was 17.29%; comparative example The initial voltage of the membrane electrode of 1 was 1.89V. After 50 hours of stability testing, the voltage increased to 2.42V, and the voltage change was 28.04%. It shows that the stability of the membrane electrode has been significantly improved after adding three-dimensional interface enhancement layers on both sides of the proton exchange membrane, especially the scheme in Example 1, the performance and stability of the membrane electrode have been significantly improved.

The carbon material in the three-dimensional interface enhancement layer in the present application has a certain three-dimensional structure, which mainly plays the role of constructing the three-dimensional contact surface between the catalytic layer and the proton exchange membrane, and reduces the contact resistance between the membrane electrode catalytic layer and the proton exchange membrane; The strength of the material can enhance the surface strength of the proton exchange membrane and prevent swelling and deformation of the proton exchange membrane during the electrolysis of water. The ionomer in the three-dimensional interface enhancement layer mainly plays a role of bonding with the carbon material, ensuring that the carbon material can be firmly bonded to the surface of the proton exchange membrane, and at the same time ensuring the contact between the three-dimensional interface enhancement layer, the proton exchange membrane and the catalytic layer. proton conductivity.

The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the patent protection scope of the present invention.

Claims (10)

1. A method for preparing a membrane electrode for producing hydrogen by electrolyzing water through PEM, which is characterized by comprising the following steps:

a. three-dimensional interface enhancement layers are respectively added on two sides of the anode and cathode of the proton exchange membrane;

b. a cathode catalytic layer and an anode catalytic layer are arranged on the surface of the cathode-anode three-dimensional interface enhancement layer of the proton exchange membrane;

c. setting a cathode gas diffusion layer and an anode gas diffusion layer on the cathode catalytic layer and the anode catalytic layer, and performing hot pressing treatment to obtain a PEM electrolytic water hydrogen production membrane electrode;

wherein the three-dimensional interface enhancement layer comprises a carbon material and an ionomer.

2. The method for producing a PEM electrolyzed water hydrogen membrane electrode according to claim 1 wherein said carbon material comprises one or more of carbon powder, carbon nanotubes, graphene and carbon nanospheres.

3. A process for preparing a PEM water electrolysis hydrogen production membrane electrode according to claim 1,

the ionomer comprises more than one of Nafion, 3M PFSA and SPEEK.

4. The method for producing a PEM electrolyzed water hydrogen membrane electrode according to claim 1 wherein step a comprises: respectively spraying the three-dimensional interface enhancement layer slurry on two sides of the anode and cathode of the proton exchange membrane to obtain an interface enhanced proton exchange membrane; wherein the three-dimensional interface enhancement layer comprises a carbon material and an ionomer.

5. A method for producing a PEM electrolyzed water hydrogen membrane electrode according to claim 4 wherein said three dimensional interfacial reinforcement layer carbon material and ionomer have a total loading of 0.1 to 1.0mg/cm ² 。

6. The method for preparing a PEM electrolyzed water hydrogen membrane electrode according to claim 4 wherein said three dimensional interface enhancement layer carbon material and ionomer are present in a mass ratio of 1: 2-2: 1.

7. the method of preparing a PEM electrolyzed water hydrogen membrane electrode according to claim 1 wherein step b comprises: respectively spraying cathode catalytic layer slurry and anode catalytic layer slurry on the surfaces of the cathode and anode three-dimensional interface enhancement layers of the proton exchange membrane, and drying to obtain a cathode catalytic layer and an anode catalytic layer which are arranged on two sides of the proton exchange membrane containing the cathode and anode three-dimensional interface enhancement layers;

wherein the cathode catalytic layer slurry comprises a cathode catalyst, a binder and a dispersing agent;

the anode catalytic layer slurry comprises an anode catalyst, a binder and a dispersing agent.

8. The method for producing a PEM electrolyzed water hydrogen membrane electrode according to claim 7 wherein said cathode catalyst slurry:

the cathode catalyst comprises more than one of Pt/C, pt black;

the binder comprises a perfluorosulfonic acid resin solution;

the dispersing agent comprises more than one of deionized water, ethanol and isopropanol;

the anode catalyst comprises IrO ₂ 、RuO ₂ More than one of Pt black;

the binder comprises a perfluorosulfonic acid resin solution;

the dispersing agent comprises more than one of deionized water, ethanol and isopropanol;

the Pt loading in the cathode catalytic layer is 0.3-1.0 mg/cm ² ；

The anode catalyst loading in the anode catalyst layer is 0.5-3.0 mg/cm ² 。

9. The PEM electrolyzed water hydrogen membrane electrode and process for making same as defined in claim 1 wherein step c comprises: a cathode gas diffusion layer and an anode gas diffusion layer are arranged on the cathode and anode catalytic layer, and the cathode gas diffusion layer and the anode gas diffusion layer are one of sintered titanium felt, titanium mesh, foam titanium, carbon cloth and carbon paper; and then, hot-pressing treatment is carried out to obtain cathode and anode gas diffusion layers arranged on two sides of the cathode catalytic layer and the anode catalytic layer, namely the PEM water electrolysis hydrogen production membrane electrode.

10. The PEM water electrolysis hydrogen production membrane electrode prepared by the preparation method according to any one of claims 1 to 9 is characterized in that the membrane electrode has the following structure: three-dimensional interface enhancement layers are arranged on two sides of a cathode and an anode of the proton exchange membrane, and a cathode catalytic layer and an anode catalytic layer are arranged on the surfaces of the three-dimensional interface enhancement layers; a cathode gas diffusion layer and an anode gas diffusion layer are respectively arranged on the cathode catalytic layer and the anode catalytic layer; 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 obviously improved, wherein when the voltage is 1.9V, the current density is improved by 17.3%; and after 50 hours of stability test, the voltage change is only 6.67%, which is reduced by 21.33%.

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