Preparation method of proton exchange membrane water electrolysis hydrogen production membrane electrode

Abstract

The invention discloses a preparation method of a proton exchange membrane water electrolysis hydrogen production membrane electrode, which comprises the following steps: firstly, pretreating a proton exchange membrane, respectively spraying cathode and anode catalyst slurry to two sides of the treated proton exchange membrane, and drying; the method comprises the following steps: putting a proton exchange membrane into a cavity of magnetron sputtering equipment, respectively carrying out sputtering coating on two sides by utilizing a Pt target and an IrO2 target, and controlling the thickness of Pt and the thickness of IrO2; and carrying out post-treatment on the prepared membrane electrode. According to the preparation method, the efficiency of the catalyst can be improved, the catalyst layer is thinner, the dosage of the catalyst is smaller, the dosage of noble metal is reduced by 90% or above compared with that of a conventional catalyst, and the hydrogen production cost is greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen production, and in particular to a method for preparing a membrane electrode for hydrogen production by proton exchange membrane electrolysis of water Background Art

[0002] Green hydrogen refers to the use of renewable energy to produce hydrogen. The production process of this hydrogen does not produce greenhouse gas emissions and is therefore considered a very environmentally friendly energy source. The importance of green hydrogen lies in the fact that it can provide us with a sustainable energy option while also helping to reduce our dependence on fossil fuels. As the world pays more and more attention to environmental issues, the application prospects of green hydrogen are becoming more and more broad.

[0003] The main problem with electrolyzing water to produce green hydrogen is the cost issue. This is because of its high potential and acidic environment, which requires the use of precious metal catalysts such as iridium and platinum. The conventional method for preparing catalysts is the slurry method or the coating method. In this method, the catalyst and the binder are first mixed into a slurry, and then the slurry is coated on the substrate to make a catalyst electrode. Due to the two-sided nature of the binder, it is necessary to master the appropriate dosage to ensure that the catalytic sites are fully exposed while maintaining the stability of the electrode. In practice, due to the large thickness of the catalyst layer, the adhesive and the substrate will cover the catalytic sites, which also leads to a large amount of catalyst used. Generally, the cathode catalyst layer contains 5g / m 2 Pt, the anode contains 5g / m 2 The increase in the amount of Ir and catalyst usage makes the cost of hydrogen production high and limits the scope of application. Summary of the invention

[0004] In order to solve the above problems, the present invention provides a method for preparing a membrane electrode for hydrogen production by proton exchange membrane water electrolysis, which can reduce the amount of catalyst used and reduce the cost of hydrogen production.

[0005] To this end, the technical solution of the present invention is: a method for preparing a proton exchange membrane water electrolysis hydrogen production membrane electrode, comprising the following steps:

[0006] 1) Proton exchange membrane pretreatment;

[0007] 2) Preparing a substrate: spraying the cathode catalyst slurry and the anode catalyst slurry onto both sides of the treated proton exchange membrane respectively, and drying;

[0008] 3) Magnetron sputtering catalyst:

[0009] 3.1) Place the proton exchange membrane in the chamber of the magnetron sputtering equipment, with the side containing the cathode catalyst as the target surface and the background vacuum of 4-5×10 -4After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8-1.2 Pa, -100 V bias was applied to the substrate, and glow cleaning was performed for 8-15 min; after glow cleaning, sputtering coating was performed, and the background vacuum was 4-5×10 -4 Pa, connect the Pt target to the RF power supply, introduce argon, the argon flow rate is 20-40sccm, the working pressure is adjusted to 0.3-0.8Pa, the Pt target power is adjusted to 80-120W, the deposition time is 10-150min, and the Pt thickness is controlled to be 20-200nm;

[0010] 3.2) The proton exchange membrane is placed back into the magnetron sputtering chamber, with the side containing the anode catalyst as the target surface and the background vacuum being 4-5×10 -4 After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8-1.2 Pa, -100 V bias was applied to the substrate, and glow cleaning was performed for 8-15 min; after glow cleaning, sputtering coating was performed, and the background vacuum was 4-5×10 -4 Pa, connect the IrO2 target to the RF power supply, introduce argon gas, the argon gas flow rate is 20-40sccm, the working pressure is adjusted to 0.3-0.8Pa, the IrO2 target power is adjusted to 80-120W, the deposition time is 10-150min, and the IrO2 thickness is controlled to be 20-200nm;

[0011] 4) Membrane electrode post-processing.

[0012] On the basis of the above scheme and as a preferred scheme of the above scheme: in the step 1) of pre-treating the proton exchange membrane, the proton exchange membrane is immersed in 8-12wt% hydrogen peroxide for 30-60 minutes, rinsed with deionized water to remove surface residues, then immersed in 4-6% sulfuric acid solution for 30-60 minutes, then rinsed with deionized water and stored in a dust-free dryer.

[0013] On the basis of the above scheme and as a preferred scheme of the above scheme: in the step 2), the step of preparing the substrate is:

[0014] 2.1) preparing cathode catalyst slurry and anode catalyst slurry with the carrier, perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9, and placing in an ultrasonic agitator for 2-2.5 hours;

[0015] 2.2) Add the cathode catalyst slurry to the spraying equipment, spray it onto the treated proton exchange membrane, and dry it; add the anode catalyst slurry to the spraying equipment, spray it onto the treated proton exchange membrane, and dry it.

[0016] On the basis of the above scheme and as a preferred scheme of the above scheme: in the step 2.1), the carrier when preparing the cathode catalyst slurry is C, and the carrier when preparing the anode catalyst slurry includes but is not limited to C, Ti, Pt, TiC, In2O3, SnO2, TiN, W x TiO2, or a combination of one or more of TiO2.

[0017] On the basis of the above scheme and as a preferred scheme of the above scheme: the thickness of the carrier in step 2.1) is 0-20 μm.

[0018] On the basis of the above scheme and as a preferred scheme of the above scheme: during the drying in step 2.2), the proton exchange membrane after spraying the slurry is placed in a heating furnace, heated from room temperature to 110-140°C, at a heating rate of 8-12°C / min, kept warm for 50-80 minutes, and then cooled naturally.

[0019] On the basis of the above scheme and as a preferred scheme of the above scheme: in the step 4), the post-processing step is:

[0020] 4.1) Acid pickling: Place the membrane electrode in a sulfuric acid solution with a concentration of 1-3 mol / L. The sulfuric acid solution is gradually heated from room temperature to 75-90°C at a heating rate of 8-12°C / min. Keep warm for 2-3 hours, cool naturally to room temperature, and place for 18-24 hours.

[0021] 4.2) Cleaning: Place the membrane electrode in deionized water, heat from room temperature to 75-90°C, at a heating rate of 8-12°C / min, and clean 3 to 4 times.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows: by utilizing the magnetron sputtering coating process, ionized argon ions bombard the target surface, causing Pt target atoms and IrO2 target atoms to sputter out and deposit on both sides of the proton exchange membrane with cathode catalyst and anode catalyst to form a thin film; this preparation method can improve the efficiency of the catalyst, the catalytic layer is thinner, the amount of catalyst used is less, and the amount of precious metal used is reduced by more than 90% compared with conventional catalysts, thereby greatly reducing the cost of hydrogen production. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a preparation flow chart of the present invention. DETAILED DESCRIPTION

[0024] Example 1

[0025] The method for preparing the proton exchange membrane water electrolysis hydrogen production membrane electrode described in this embodiment comprises the following steps:

[0026] 1) Proton exchange membrane pretreatment: The proton exchange membrane is immersed in 10wt% hydrogen peroxide for 30-60min, rinsed with deionized water to remove surface residues, then immersed in 5% sulfuric acid solution for 30-60min, then rinsed with deionized water and stored in a dust-free dryer.

[0027] 2) Preparation of substrate:

[0028] 2.1) The cathode carrier is mixed with perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9 to form a cathode catalyst slurry, and placed in an ultrasonic stirrer for 2 hours. The cathode carrier is C, carbon;

[0029] 2.2) The anode carrier is prepared into an anode catalyst slurry with a perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9, and placed in an ultrasonic stirrer for 2 hours. The anode carrier is a combination of C and Ti;

[0030] 2.3) Add the cathode catalyst slurry to the spraying equipment, spray it onto one side of the treated proton exchange membrane, and then dry it. During drying, put the membrane after spraying the slurry into a heating furnace, heat it from room temperature to 120°C, at a heating rate of 10°C / min, keep it warm for 60 minutes, and then cool it naturally;

[0031] 2.4) Add the anode catalyst slurry to the spraying equipment, spray it onto the other side of the proton exchange membrane, and then dry it. During drying, put the membrane after spraying the slurry into a heating furnace, heat it from room temperature to 120°C, at a heating rate of 10°C / min, keep it warm for 60 minutes, and then cool it naturally.

[0032] 3) Magnetron sputtering catalyst:

[0033] 3.1) Place the proton exchange membrane with catalyst slurry sprayed on both sides into the chamber of the magnetron sputtering equipment, first sputter the cathode catalyst, and use the side with the cathode catalyst as the target surface; the background vacuum is 5×10 -4 After 1.0 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 1.0 Pa, a bias of -100 V was applied to the substrate, and the glow cleaning was performed for 10 min. After the glow cleaning, sputtering coating was performed, and the background vacuum was 5×10 -4 Pa, connect the Pt target to the RF power supply, introduce argon gas, the argon flow rate is 30sccm, the working gas pressure is adjusted to 0.5Pa, the Pt target power is adjusted to 100W, the deposition time is 30min, and the Pt thickness is controlled to be 40nm.

[0034] 3.2) Turn the proton exchange membrane over and put it back into the magnetron sputtering equipment chamber, with the side with the anode catalyst as the target surface. The background vacuum is 5×10 -4After 1.0 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 1.0 Pa, a bias of -100 V was applied to the substrate, and the glow cleaning was performed for 10 min. After the glow cleaning, sputtering coating was performed, and the background vacuum was 5×10 -4 Pa, connect the IrO2 target to the RF power supply, introduce argon gas, the argon flow rate is 30sccm, the working gas pressure is adjusted to 0.5Pa, the IrO2 target power is adjusted to 100W, the deposition time is 30min, and the IrO2 thickness is controlled to be 40nm.

[0035] The order of the above steps 3.1) and 3.2) can be interchanged.

[0036] 4) The prepared membrane electrode (MEA) needs to be post-processed:

[0037] 4.1) Acid pickling: The MEA dry membrane was placed in a 2 mol / L sulfuric acid solution, and the temperature of the sulfuric acid solution was gradually raised from room temperature to 80°C at a rate of 10°C / min, and kept at this temperature for 2 to 3 hours, and then naturally cooled to room temperature and placed for 24 hours.

[0038] 4.2) Cleaning treatment: Place the MEA membrane in deionized water, heat it from room temperature to 80°C at a heating rate of 10°C / min, and clean it 3 to 4 times.

[0039] Table 1: Ir mass in IrO2 in Example 1

[0040]

[0041]

[0042] As shown in Table 1, in the preparation process of the membrane electrode, the thickness of IrO2 is 40nm and the thickness of 1cm 2 Taking area as an example, the volume of IrO2 is 0.000004cm 3 The density of IrO2 is 11.665 g / cm 3 , then the mass of IrO2 is 0.04666 mg / cm 2 , where the mass of Ir is 0.040000232 mg / cm 2 In the prior art, the anode catalyst contains 0.5 mg / cm 2 The amount of Ir in the MEA prepared in this embodiment is reduced by 92%, which greatly reduces the cost of hydrogen production.

[0043] Table 2: Pt mass table in Example 1

[0044]

[0045] As shown in Table 2, in the preparation process of this membrane electrode, the Pt thickness is 40nm and the2 Taking area as an example, the volume of Pt is 0.000004cm 3 , the density of Pt is 21.45 g / cm 3 , then the mass of Pt is 0.0858 mg / cm 2 In the prior art, the cathode catalyst contains 0.5 mg / cm 2 The amount of Pt in the MEA prepared in this embodiment is reduced by 85%, which greatly reduces the cost of hydrogen production.

[0046] Example 2

[0047] The method for preparing the proton exchange membrane water electrolysis hydrogen production membrane electrode described in this embodiment comprises the following steps:

[0048] 1) Proton exchange membrane treatment: The proton exchange membrane was immersed in 12 wt% hydrogen peroxide for 45 min, rinsed with deionized water to remove surface residues, then immersed in 6% sulfuric acid solution for 45 min, then rinsed with deionized water and stored in a dust-free dryer.

[0049] 2) Preparation of substrate:

[0050] 2.1) The cathode carrier is mixed with perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9 to form a cathode catalyst slurry, and placed in an ultrasonic agitator for 2.5 hours. The cathode carrier is C, carbon;

[0051] 2.2) The anode carrier is prepared into an anode catalyst slurry with a perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9, and placed in an ultrasonic stirrer for 2.5 hours. The anode carrier is a combination of TiC and In2O3;

[0052] 2.3) Add the cathode catalyst slurry to the spraying equipment, spray it onto one side of the treated proton exchange membrane, and then dry it. During drying, put the membrane after spraying the slurry into a heating furnace, heat it from room temperature to 140°C, at a heating rate of 8°C / min, keep it warm for 80 minutes, and then cool it naturally;

[0053] 2.4) Add the anode catalyst slurry to the spraying equipment, spray it onto the other side of the proton exchange membrane, and then dry it. During drying, put the membrane after spraying the slurry into a heating furnace, heat it from room temperature to 140°C, at a heating rate of 8°C / min, keep it warm for 80 minutes, and then cool it naturally.

[0054] 3) Magnetron sputtering catalyst:

[0055] 3.1) Place the proton exchange membrane with catalyst slurry sprayed on both sides into the chamber of the magnetron sputtering equipment, first sputter the cathode catalyst, and use the side with the cathode catalyst as the target surface; the background vacuum is 4×10 -4 After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8 Pa, a -100 V bias was applied to the substrate, and the glow cleaning was performed for 12 minutes. After the glow cleaning, sputtering coating was performed, and the background vacuum was 4×10 -4 Pa, connect the Pt target to the RF power supply, introduce argon gas, the argon flow rate is 40sccm, the working gas pressure is adjusted to 0.6Pa, the Pt target power is adjusted to 120W, the deposition time is 60min, and the Pt thickness is controlled to be 80nm.

[0056] 3.2) The proton exchange membrane was turned over and placed back into the chamber of the magnetron sputtering equipment, with the side with the anode catalyst as the target surface. The background vacuum was 4×10 -4 After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8 Pa, a bias voltage of -100 V was applied to the substrate, and the glow cleaning was performed for 12 minutes. After the glow cleaning, sputtering coating was performed, and the background vacuum was 4×10 -4 Pa, connect the IrO2 target to the RF power supply, introduce argon gas, the argon flow rate is 40sccm, the working gas pressure is adjusted to 0.6Pa, the IrO2 target power is adjusted to 120W, the deposition time is 60min, and the IrO2 thickness is controlled to be 80nm.

[0057] 4) The prepared membrane electrode (MEA) needs to be post-processed:

[0058] 4.1) Acid pickling: The MEA dry membrane was placed in a 3 mol / L sulfuric acid solution, and the temperature of the sulfuric acid solution was gradually raised from room temperature to 75°C at a rate of 8°C / min, and kept at this temperature for 3 h, and then naturally cooled to room temperature and placed for 20 h.

[0059] 4.2) Cleaning treatment: Place the MEA membrane in deionized water, heat it from room temperature to 75°C at a heating rate of 8°C / min, and clean it 3 to 4 times.

[0060] Table 3: Ir mass in IrO2 in Example 2

[0061]

[0062]

[0063] Table 4: Pt mass table in Example 2

[0064]

[0065] As shown in Table 3, in the preparation process of this membrane electrode, the thickness of IrO2 is 80nm and the thickness of 1cm 2Taking area as an example, the volume of IrO2 is 0.000008cm 3 The density of IrO2 is 11.665 g / cm 3 , then the mass of IrO2 is 0.09332 mg / cm 2 , where the mass of Ir is 0.080000464 mg / cm 2 .

[0066] As shown in Table 4, in the preparation process of this membrane electrode, the Pt thickness is 80nm and the 2 Taking area as an example, the volume of Pt is 0.000008cm 3 , the density of Pt is 21.45 g / cm 3 , then the mass of Pt is 0.1716 mg / cm 2 .

[0067] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A method for preparing a membrane electrode for producing hydrogen by electrolysis of water using a proton exchange membrane, characterized in that: The following steps are involved: 1) Proton exchange membrane pretreatment; 2) Preparing a substrate: spraying the cathode catalyst slurry and the anode catalyst slurry onto both sides of the treated proton exchange membrane respectively, and drying; 3) Magnetron sputtering catalyst: 3.1) Place the proton exchange membrane in the chamber of the magnetron sputtering equipment, with the side containing the cathode catalyst as the target surface and the background vacuum of 4-5×10 -4 After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8-1.2 Pa, -100 V bias was applied to the substrate, and glow cleaning was performed for 8-15 min; after glow cleaning, sputtering coating was performed, and the background vacuum was 4-5×10 -4 Pa, connect the Pt target to the RF power supply, introduce argon, the argon flow rate is 20-40sccm, the working pressure is adjusted to 0.3-0.8Pa, the Pt target power is adjusted to 80-120W, the deposition time is 10-150min, and the Pt thickness is controlled to be 20-200nm; 3.2) The proton exchange membrane is placed back into the chamber of the magnetron sputtering equipment, with the side containing the anode catalyst as the target surface and the background vacuum being 4-5×10 -4 After 1000 Pa, argon gas was introduced, the pressure in the sputtering chamber was controlled to be 0.8-1.2 Pa, -100 V bias was applied to the substrate, and glow cleaning was performed for 8-15 min; after glow cleaning, sputtering coating was performed, and the background vacuum was 4-5×10 -4 Pa, connect the IrO2 target to the RF power supply, introduce argon gas, the argon gas flow rate is 20-40sccm, the working pressure is adjusted to 0.3-0.8Pa, the IrO2 target power is adjusted to 80-120W, the deposition time is 10-150min, and the IrO2 thickness is controlled to be 20-200nm; 4) Membrane electrode post-processing.

2. The method for preparing a proton exchange membrane water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: In the step 1) of pre-treating the proton exchange membrane, the proton exchange membrane is immersed in 8-12wt% hydrogen peroxide for 30-60 minutes, rinsed with deionized water to remove surface residues, then immersed in 4-6% sulfuric acid solution for 30-60 minutes, then rinsed with deionized water, and stored in a dust-free dryer.

3. The method for preparing a proton exchange membrane water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: In the step 2), the steps of preparing the substrate are: 2.1) preparing cathode catalyst slurry and anode catalyst slurry with the carrier, perfluorinated resin solution, isopropanol, anhydrous ethanol and distilled water in a mass ratio of 1:10:40:40:9, and placing in an ultrasonic agitator for 2-2.5 hours; 2.2) Add the cathode catalyst slurry to the spraying equipment, spray it onto the treated proton exchange membrane, and dry it; add the anode catalyst slurry to the spraying equipment, spray it onto the treated proton exchange membrane, and dry it.

4. The method for preparing a proton exchange membrane water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: In the step 2.1), the carrier for preparing the cathode catalyst slurry is C, and the carrier for preparing the anode catalyst slurry includes but is not limited to C, Ti, Pt, TiC, In2O3, SnO2, TiN, W x TiO2, or a combination of one or more of TiO2.

5. The method for preparing a proton exchange membrane water electrolysis hydrogen production membrane electrode according to claim 1, characterized in that: The thickness of the carrier in step 2.1) is 0-20 μm.

6. The method for preparing a membrane electrode for producing hydrogen by proton exchange membrane water electrolysis as claimed in claim 1, characterized in that: During the drying step 2.2), the proton exchange membrane after spraying the slurry is placed in a heating furnace, heated from room temperature to 110-140° C., at a heating rate of 8-12° C. / min, kept warm for 50-80 min, and then cooled naturally.

7. The method for preparing a membrane electrode for producing hydrogen by proton exchange membrane water electrolysis as claimed in claim 1, characterized in that: In the step 4), the post-processing step is: 4.1) Acid pickling: Place the membrane electrode in a sulfuric acid solution with a concentration of 1-3 mol / L. The sulfuric acid solution is gradually heated from room temperature to 75-90°C at a heating rate of 8-12°C / min. Keep warm for 2-3 hours, cool naturally to room temperature, and place for 18-24 hours. 4.2) Cleaning: Place the membrane electrode in deionized water, heat from room temperature to 75-90°C, at a heating rate of 8-12°C / min, and clean 3 to 4 times.

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