Preparation method of water electrolysis functional catalyst

Abstract

The invention relates to the technical field of catalyst preparation, in particular to a method for preparing a water electrolysis functional catalyst, and the main technical scheme is as follows: calcining conductive carbon black, ball-milling, pickling, filtering and drying to obtain a carbon carrier; fully mixing an alkali solution, a chloroplatinic acid solution and the carbon carrier slurry, and uniformly dispersing to obtain platinum-carbon precursor slurry; carrying out vacuum treatment on the platinum-carbon precursor slurry, and stirring the slurry in the treatment process; transferring the system into a reaction device for reaction; and after the reaction is finished, filtering and drying the solution to obtain the water electrolysis functional catalyst. According to the preparation method of the water electrolysis functional catalyst, a carbon carrier structure is optimized through calcination, ball milling and acid pickling, and high-dispersion loading of platinum nanoparticles is achieved by combining uniform mixing, vacuum stirring and hydrothermal reaction of an alkali solution and chloroplatinic acid.

Description

Technical Field

[0001] The invention relates to the technical field of catalyst preparation, in particular to a method for preparing a water electrolysis functional catalyst. Background Art

[0002] Energy underpins human life and economic development. Currently, coal, oil, and natural gas are the primary energy sources for industrial production and consumer consumption. However, the continued development of the global economy and rising per capita energy consumption have led to a significant increase in energy demand. However, the reserves of non-renewable energy are limited, forcing the search for new renewable energy sources. Hydrogen energy, with its wide availability, environmental friendliness, high calorific value, and storable and renewable energy, is currently the most promising green energy source.

[0003] Both the anode and cathode of PEM water electrolysis utilize precious metal catalysts, making improving catalyst activity and durability a critical task in this technology. Platinum-carbon catalysts primarily act on the cathode hydrogen evolution reaction during water electrolysis and are currently the mainstream commercial catalyst. Improving the dispersion of Pt particles, increasing Pt utilization, and extending the life of Pt / C catalysts are crucial for the commercialization of PEM water electrolysis technology. Summary of the Invention

[0004] The purpose of the present invention is to prepare a water electrolysis functional catalyst, which has high durability and strong binding force between the carrier and the precious metal particles, thereby greatly improving the catalyst life.

[0005] The present invention provides a method for preparing a water electrolysis functional catalyst, comprising the following steps:

[0006] The conductive carbon black is calcined, ball-milled, acid-washed, filtered, and dried to obtain a carbon support;

[0007] The alkaline solution, chloroplatinic acid solution and carbon support slurry are fully mixed and dispersed uniformly to obtain a platinum-carbon precursor slurry;

[0008] The platinum-carbon precursor slurry is vacuum treated, and the slurry needs to be stirred during the treatment process;

[0009] Transferring the above system to a reaction device to carry out the reaction;

[0010] After the reaction is completed, the solution is filtered and dried to obtain the water electrolysis functional catalyst.

[0011] Furthermore, the conductive carbon black is one or more of porous carbon black, carbon nanotubes, mesoporous carbon, and carbon nanofibers.

[0012] Furthermore, the mixed acid solution is any one of nitric acid, a mixed solution of nitric acid and sulfuric acid, and a mixed solution of nitric acid, sulfuric acid and hydrochloric acid.

[0013] Furthermore, the alkaline solution is one of sodium bicarbonate, potassium hydroxide, sodium hydroxide, and calcium hydroxide solution, with a mass fraction of 5-15%.

[0014] Furthermore, the carbon carrier slurry is a mixture of the treated carrier and one or more solutions of water, ethanol, isopropanol, n-propanol, ethylene glycol, and glycerol, and the mass fraction of the carbon carrier is 0.3-1.0%.

[0015] Furthermore, in the chloroplatinic acid solution, the mass fraction of chloroplatinic acid is 1-2%.

[0016] Furthermore, the vacuum device is one of a vacuum generator, an oil-free diaphragm vacuum pump, a water ring pump, a sputtering ion pump, and a cryogenic pump.

[0017] Furthermore, the system temperature is constant, and the effects of potential temperature changes caused by vacuum on viscosity are ignored. The ethylene glycol solution is considered a Newtonian fluid, with a constant viscosity (η) that does not vary with shear rate. The flow of the fluid within the pores of the carbon support is laminar (low Reynolds number), which complies with the conditions for Darcy's law. The porous carbon support is considered an isotropic and structurally uniform porous medium. Before vacuum treatment, the pores of the carbon support are filled with gas (usually air). Applying a vacuum (P) to the system has the effect of reducing the gas pressure within the pores of the porous carbon support. When the carbon support is immersed in the ethylene glycol solution and vacuum is applied, the vacuum acts to overcome the resistance of the residual gas in the pores and the viscous resistance of the liquid, driving the liquid (ethylene glycol) to penetrate and fill the pores. The driving force for the liquid to penetrate the pore front is primarily the applied vacuum pressure differential.

[0018] Furthermore, the permeability of porous media is related to its porosity ( ) show a strong correlation. Increasing the pore size or particle size of the constituent particles significantly increases the percolation rate, and macroporous materials are easier to impregnate than microporous materials. For materials of different porosities, at the same vacuum level and viscosity, increasing porosity increases the material's permeation rate. Higher solution viscosity significantly slows the percolation rate. To achieve the same percolation rate at higher viscosities, greater pressure is required, and the higher the vacuum level, the greater the pressure.

[0019] Furthermore, the vacuum degree (P) should be determined based on the viscosity of the slurry (η) and the porosity of the carbon support ( ) are dynamically adjusted to ensure efficient removal of dissolved oxygen and facilitate platinum precursor penetration: ;

[0020] P base : basic vacuum degree (e.g. 5 kPa, which can be optimized based on experiments, P is the absolute pressure value, and a smaller value indicates high vacuum);

[0021] η: actual viscosity of slurry (unit: mPa·s);

[0022] η0: reference viscosity (e.g., pure water viscosity 1 mPa·s);

[0023] : actual porosity of the carbon support;

[0024] 0: reference porosity (e.g. 0.5);

[0025] k1, k2: empirical coefficients (e.g. k1=-0.3, k2=0.5).

[0026] The traditional fixed vacuum degree may lead to incomplete degassing of high-viscosity slurries, and the platinum precursor fails to fully penetrate the pores of the carbon support, eventually forming large-sized Pt particles (>5 nm), which reduces the catalytic activity. For high-viscosity slurries (such as those containing ethylene glycol), the vacuum degree is automatically increased (such as adjusting the pressure gauge value from 5kPa to 15kPa) to forcibly remove bubbles and dissolved oxygen, making it easier for the Pt precursor to enter the micropores of the support. The average particle size of the Pt particles can be controlled below 3nm, and the specific surface area is increased; the difference in the porosity of the carbon support will affect the anchoring effect of Pt. Low-porosity supports require a higher vacuum degree to ensure the penetration of the precursor. The formula is based on the porosity ( ) automatically reduces the target vacuum degree (e.g. when the porosity is 30%, P∝1 / ), enhance the binding force between Pt and the carrier.

[0027] Furthermore, the conductive carbon black is calcined by heating it to 1500-2000° C. in a nitrogen protective atmosphere and keeping the temperature for 60-180 minutes.

[0028] Furthermore, the mass ratio of the alkaline solution, the chloroplatinic acid solution and the carbon support slurry is 1:9.9:14.94.

[0029] Further, the reaction system is heated to 90-130° C. and kept warm for 30-180 min before the heating is terminated.

[0030] In summary, the present invention has the following beneficial effects:

[0031] This invention provides a method for preparing a highly efficient water electrolysis catalyst. This method optimizes the carbon support structure through calcination, ball milling, and acid washing. This method, combined with uniform mixing of an alkaline solution and chloroplatinic acid, vacuum stirring, and a hydrothermal reaction, achieves highly dispersed loading of platinum nanoparticles. This method is process-controllable, has low energy consumption, and the resulting catalyst exhibits high activity and excellent stability. It is suitable for use in proton exchange membrane or alkaline water electrolysis hydrogen production systems and has potential for industrial application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 CV graphs of the supported platinum-carbon catalyst provided in Example 1 and the catalyst provided in Comparative Example 1;

[0033] Figure 2 LSV diagrams of the supported platinum-carbon catalyst provided in Example 1 and the catalyst provided in Comparative Example 1;

[0034] Figure 3 CV graphs of the supported platinum-carbon catalyst provided in Example 1 and the catalyst provided in Comparative Example 2;

[0035] Figure 4 LSV diagrams of the supported platinum-carbon catalyst provided in Example 1 and the catalyst provided in Comparative Example 2;

[0036] Figure 5 CV graphs of the supported platinum-carbon catalyst provided in Example 1 before and after 30,000 CV cycle tests;

[0037] Figure 6 This is a TEM image of the supported platinum-carbon catalyst provided in Example 1. DETAILED DESCRIPTION

[0038] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, a method for preparing a water electrolysis functional catalyst proposed in the present invention, its specific implementation method, characteristics and effects are described in detail as follows.

[0039] A method for preparing a water electrolysis functional catalyst,

[0040] The following steps are involved:

[0041] After calcining, the conductive carbon black is transferred to a ball mill, the carrier is ground to the required particle size, pickled in a mixed acid solution, filtered after pickling, filtered until the filtrate conductivity is ≤0.35μs / cm, and transferred to a vacuum drying oven at 80-90℃ for drying;

[0042] The alkaline solution, chloroplatinic acid solution and carbon support slurry are fully mixed according to the mass ratio and dispersed uniformly to obtain a platinum-carbon precursor slurry;

[0043] Transfer the platinum-carbon precursor slurry to a high-pressure resistant reaction device, seal the device, connect a vacuum pump, and perform vacuum treatment at a vacuum degree of 0.1 MPa. Stir the slurry during the treatment process.

[0044] Transferring the above system to a reaction device to carry out a hydrothermal reaction;

[0045] Heat the reaction system to 90-130°C, keep warm for 30-180 minutes, then stop heating. When the solution cools to room temperature, add strong acid to adjust the solution pH to <5, add a certain amount of ethanol, filter, transfer to a filter, filter with ultrapure water 5-10 times, transfer to a vacuum drying oven at 70-90°C and vacuum dry for 8-12 hours to obtain a dry catalyst sample.

[0046] It is understandable that the vacuum step (-0.1MPa) is used in the preparation of functional catalysts for water electrolysis. The principle is to remove dissolved gases and bubbles in the slurry through a negative pressure environment, prevent oxygen from interfering with the reduction process of the platinum precursor, and promote the full penetration of the chloroplatinic acid solution into the pores of the carbon support, so that the platinum nanoparticles are evenly distributed. The benefits of this step are: improving the uniformity and utilization of platinum loading, reducing precious metal agglomeration, and enhancing catalytic activity and stability; preventing bubbles from destroying the support structure during the subsequent hydrothermal and drying processes, ensuring a high specific surface area and conductivity of the catalyst; in addition, vacuum treatment can optimize the contact efficiency of the reactants, making the hydrothermal reaction more controllable, and ultimately improving the overall performance and cost-effectiveness of the catalyst.

[0047] In some preferred embodiments, the conductive carbon black is one or more of porous carbon black, carbon nanotubes, mesoporous carbon, and carbon nanofibers.

[0048] In some preferred embodiments, the mixed acid solution is any one of nitric acid, a mixed solution of nitric acid and sulfuric acid, and a mixed solution of nitric acid, sulfuric acid, and hydrochloric acid.

[0049] In some preferred embodiments, the alkaline solution is one of sodium bicarbonate, potassium hydroxide, sodium hydroxide, and calcium hydroxide solution, with a mass fraction of 5-15%.

[0050] In some preferred embodiments, the carbon carrier slurry is a mixture of the treated carrier and one or more solutions of water, ethanol, isopropanol, n-propanol, ethylene glycol, and glycerol, and the mass fraction of the carbon carrier is 0.3-1.0%.

[0051] In some preferred embodiments, the mass fraction of chloroplatinic acid in the chloroplatinic acid solution is 1-2%.

[0052] In some preferred embodiments, the vacuum device is one of a vacuum generator, an oil-free diaphragm vacuum pump, a water ring pump, a sputtering ion pump, and a cryogenic pump.

[0053] Among them, the vacuum degree (P) should be based on the viscosity of the slurry (η) and the porosity of the carbon support ( ) are dynamically adjusted to ensure efficient removal of dissolved oxygen and facilitate platinum precursor penetration:

[0054] ;

[0055] P base : basic vacuum degree (e.g. 5 kPa, which can be optimized based on experiments, P is the absolute pressure value, and a smaller value indicates high vacuum);

[0056] η: actual viscosity of slurry (unit: mPa·s);

[0057] η0: reference viscosity (e.g., pure water viscosity 1 mPa·s);

[0058] : actual porosity of the carbon support;

[0059] 0: reference porosity (e.g. 0.5);

[0060] k1, k2: empirical coefficients (e.g. k1=-0.3, k2=0.5).

[0061] The traditional fixed vacuum degree may lead to incomplete degassing of high-viscosity slurries, and the platinum precursor fails to fully penetrate the pores of the carbon support, eventually forming large-sized Pt particles (>5 nm), which reduces the catalytic activity. For high-viscosity slurries (such as those containing ethylene glycol), the vacuum degree is automatically increased (such as adjusting the pressure gauge value from 5 kPa to 15 kPa) to forcibly remove bubbles and dissolved oxygen, making it easier for the Pt precursor to enter the micropores of the support. The average particle size of the Pt particles can be controlled below 3nm, and the specific surface area is increased; the difference in the porosity of the carbon support will affect the anchoring effect of Pt. Low-porosity supports require a higher vacuum degree to ensure the penetration of the precursor. The formula is based on the porosity ( ) automatically reduces the target vacuum degree (e.g. when the porosity is 30%, P∝1 / ), enhance the binding force between Pt and the carrier.

[0062] In some preferred embodiments, the conductive carbon black is calcined by heating to 1500-2000° C. in a nitrogen protective atmosphere and keeping the temperature for 60-180 minutes.

[0063] In some preferred embodiments, the mass ratio of the alkaline solution, the chloroplatinic acid solution and the carbon support slurry is 1:9.9:14.94.

[0064] In some preferred embodiments, the hydrothermal reaction is to heat the reaction system to 90-130° C., keep the temperature for 30-180 minutes, and then terminate the heating.

[0065] Example 1

[0066] This embodiment 1 provides a method for preparing a water electrolysis functional catalyst

[0067] The method provided in this embodiment is as follows:

[0068] S1. Place the conductive carbon black in a crucible, heat it to 2000℃, keep it warm for 60 minutes, take it out after the sample cools down, transfer it to a ball mill, grind the carrier to the required particle size, pickle it in a mixed acid solution, filter it after pickling, filter it until the conductivity of the filtrate is ≤0.35μs / cm, and transfer it to a vacuum drying oven at 80℃ for drying.

[0069] S2. At room temperature, mix 0.5 g of treated conductive carbon black with 103 g of ethylene glycol solution, add 69 g of chloroplatinic acid solution containing 0.5 g of platinum dropwise, mix the slurry evenly with an ultrasonic device, add 7 g of 10% potassium hydroxide solution by mass, transfer the mixed solution to a sealed reaction device, connect a vacuum pump to vacuum the solution system, and continue stirring for 120 minutes.

[0070] S3. Transfer the mixed solution to a microwave chemical reaction device, heat it to 130°C and keep it warm for 30-60 seconds until the reaction is complete, cool it to room temperature, add concentrated hydrochloric acid dropwise to adjust the pH of the solution to ≤3, add a certain amount of ethanol, and stir evenly.

[0071] S4. Transfer the mixed solution of the catalyst and alcohol to a positive pressure filter, add a certain amount of ultrapure water, apply pressure and begin filtration. Repeat this step 10 times. Measure the filtrate conductivity to <2.0 μS / cm. Remove the filter cake and dry the catalyst in a vacuum drying oven at 85°C for 10 hours to obtain 1 g of a dry platinum-carbon catalyst with a 50% platinum content.

[0072] Among them, the vacuum degree (P) is determined by the viscosity of the slurry (η) and the porosity of the carbon support ( ) is dynamically adjusted, the formula is as follows:

[0073] ;

[0074] P base : basic vacuum degree (5 kPa);

[0075] η: actual viscosity of slurry (unit: mPa·s);

[0076] η0: reference viscosity (pure water viscosity 1 mPa·s);

[0077] : actual porosity of the carbon support;

[0078] 0: reference porosity (0.5);

[0079] k1, k2: empirical coefficients (k1=-0.3, k2=0.5).

[0080] Example 2

[0081] This embodiment 2 provides a method for preparing a water electrolysis functional catalyst

[0082] S1. Use a shearing device to mix 425g of chloroplatinic acid solution containing 3g of platinum and 2g of conductive carbon black slurry. Add 5g of sodium hydroxide solid and continue stirring until the solid is completely dissolved. Transfer the mixed solution to a round-bottom flask, connect a vacuum pump, and vacuum-treat the solution system while stirring.

[0083] S2. After stirring for 120 minutes, preheat the oil bath reaction device to 120°C and keep it in the device at 120°C for 40 minutes to complete the reaction. After the reaction solution is cooled to room temperature, 7.5 ml of concentrated hydrochloric acid is added dropwise to adjust the pH to ≤2.5, and a certain amount of ethanol solution is added to mix evenly.

[0084] S3. Transfer the mixed solution of the catalyst and alcohol to a positive pressure filter, use a 0.1 micron microporous filter membrane, add 800 ml of ultrapure water, pressurize to 0.2 MPa and begin filtering. Repeat this step 20 times, measure the filtrate conductivity to be less than 3 μS / cm, and obtain a wet platinum-carbon catalyst. Transfer the catalyst to a vacuum drying oven and dry it at 85°C for 12 hours to obtain 5 g of a dry platinum-carbon catalyst with a 60% platinum content.

[0085] Example 3

[0086] This embodiment 3 provides a method for preparing a functional catalyst for water electrolysis

[0087] S1. At room temperature, ultrasonically mix 6 g of boron-doped carbon nanotubes and an alcohol solution with a mass ratio of ethylene glycol to propylene glycol of 2:1. Then, add 60 g of a 10% sodium hydroxide solution to 600 g of a chloroplatinic acid solution containing 4 g of platinum. Shear and disperse for 40 min, keeping the temperature below a certain level, and stir for 120 min.

[0088] S2. Transfer the mixed solution to a reactor, connect a vacuum generator, seal the reaction apparatus, and begin vacuum treatment for 120 minutes while continuing to stir. Raise the reactor temperature to 125°C and maintain for 90 minutes to complete the reaction. After the reaction solution cools to room temperature, add 10 ml of concentrated hydrochloric acid dropwise while stirring to adjust the pH to ≤3. Add a certain amount of ethanol and mix thoroughly.

[0089] S3. Transfer the catalyst mixture solution to a positive pressure filter, pressurize it to 0.3 MPa and begin filtering. After the solvent is completely filtered out, open the vent valve to release the pressure, then add a certain amount of ultrapure water and pressurize and begin filtering. Repeat the above steps 20 times. Measure the filtrate conductivity to be less than 3.5 μS / cm. Remove the filter cake and place it in a vacuum drying oven at 85°C for 13 hours to completely evaporate the water, thereby obtaining 10 g of a dry platinum-carbon catalyst with a 40% platinum content.

[0090] Example 4

[0091] This embodiment 4 provides a method for preparing a water electrolysis functional catalyst

[0092] S1. At room temperature, ultrasonically disperse 25g of mesoporous carbon in a propylene glycol-water solution with a mass ratio of 3:1. After the solution is evenly dispersed, add 1725g of a chloroplatinic acid-alcohol solution containing 25g of platinum and 173g of a 10% sodium hydroxide solution. Shear and disperse for 40 minutes, keeping the temperature below zero.

[0093] S2. Transfer the mixed solution to a reactor, connect a vacuum pump, seal the connection of the device, and stir under vacuum for 120 minutes. Heat the completely mixed slurry to 130°C and keep it warm for 120 minutes to complete the reaction. After the reaction solution is cooled to below 40°C, add 30 ml of concentrated hydrochloric acid and adjust the pH to ≤2.3.

[0094] S3. The catalyst mixed solution was allowed to stand for stratification, the upper clear layer was poured out, and the remaining solution was transferred to a positive pressure filter. A microporous filter membrane with a pore size of 0.4 μm was used. Ultrapure water twice the volume of the remaining solution was added and pressurized to 0.3 MPa to start filtering. When there was about 300 ml of liquid remaining in the filter, the air valve was opened to release the pressure. Then 800 ml of ultrapure water was added and pressurized to 0.3 MPa to start filtering. Repeat the steps 20-25 times, and the filtrate conductivity was measured to be <3.8 μS / cm. The wet catalyst was placed in a vacuum drying oven and heated at 85 ° C for 15 hours to obtain 50 g of a dry platinum-carbon catalyst with a platinum content of 50%.

[0095] Comparative Example 1: Tanaka Precious Metals TEC10E50E catalyst 50% platinum carbon catalyst.

[0096] Comparative Example 2

[0097] A self-made 50% platinum-carbon catalyst sample without vacuum treatment was prepared in the same manner as in Example 1, except that the vacuum treatment step was omitted.

[0098] Performance Testing

[0099] Comparative Example 1 and Comparative Example 2 show the catalyst performance. Figure 3 and Figure 4After 20 cycles of activation in 0.5M sulfuric acid solution, the electrochemical surface area (ECSA) of the platinum-carbon catalyst PT50 prepared in Example 1 of the present invention was 56.5m 2 / g, the comparative example 250% platinum carbon catalyst is 51.98m 2 / g, indicating that the prepared platinum-carbon catalyst has good performance; under oxygen saturation, the sweep rate was 10mV / s, the sweep voltage was -0.2-0.7 (vs, saturated calomel electrode, SCE), and the rotation speed was 1600rpm. The mass activity of the platinum-carbon catalyst PT50 prepared in Example 1 of the present invention was 52.7mA / mg (vs, saturated calomel electrode, SCE), indicating that the platinum-carbon catalyst PT50 has a high oxygen reduction catalytic activity, while the 50% platinum-carbon catalyst of Comparative Example 2 is 46.3mA / mg (vs, saturated calomel electrode, SCE). The vacuum treatment allows more platinum precursor solution to enter the micropores of the carbon support, thereby improving the dispersion of platinum during the preparation process, allowing platinum to provide more active sites in the electrolysis of water reaction, and showing a higher electrochemical surface area and mass activity in the electrochemical performance, thereby improving the utilization rate of the catalyst.

[0100] The life test of Example 1 was carried out. After 30,000 CV cycles, the electrochemical surface area (ECSA) of the sample of Example 1 was 42.08 m 2 / g, the attenuation rate is 25.5%. Figure 5 .

[0101] Specifically, after 20 cycles of activation in 0.5M sulfuric acid solution, the platinum-carbon catalyst PT50 prepared in Example 1 of the present invention exhibited a 56.5m 2 / g electrochemical surface area (ECSA), which is 51.98m / g compared with the 50% Pt / C catalyst in Comparative Example 2. 2 / g has been significantly improved, and behind this seemingly subtle improvement lies multiple key advantages to catalyst performance.

[0102] Electrochemical surface area (ECSA) is a core indicator for measuring the number of active sites on a catalyst. An increase in the value indicates a larger active area per gram of catalyst and a richer number of active sites available for electrochemical reactions. More active sites allow the catalyst to better adsorb and desorb protons and hydrogen molecules during the water electrolysis reaction. The creation of pores helps reaction products escape from the reaction system more quickly, thereby accelerating the reaction process and improving water electrolysis efficiency. Specifically, under an oxygen-saturated environment, at a scan rate of 10 mV / s, a scan voltage range of -0.2-0.7 V (vs, saturated calomel electrode, SCE), and a rotation speed of 1600 rpm, the platinum-carbon catalyst PT50 of Example 1 exhibited a mass activity of 52.7 mA / mg (vs, saturated calomel electrode, SCE), higher than the 46.3 mA / mg (vs, saturated calomel electrode, SCE) of Comparative Example 2. This is a direct reflection of the improved ECSA. The abundant active sites provide more "reaction sites" for the oxygen reduction reaction, significantly improving the efficiency of the catalytic reaction.

[0103] At the same time, the higher ECSA at the same platinum loading also reflects the excellent dispersion of platinum on the carbon support. The present invention uses a vacuum treatment process to allow more platinum precursor solution to enter the micropores of the carbon support, significantly improving the dispersion of platinum, which not only allows 56.5m 2 / g ECSA is possible, which means that the utilization rate of platinum has been effectively improved. In traditional catalysts, if the platinum particles are unevenly dispersed, some platinum may be wrapped or aggregated and unable to participate in the reaction, resulting in a waste of precious metal resources. 2 / g ECSA indicates that platinum particles can be more evenly distributed on the carrier surface and penetrate deep into the micropores. The "potential" of every inch of platinum is more fully stimulated, and stronger catalytic efficiency is exerted at the same platinum loading. This is of great significance for reducing catalyst costs and improving economic efficiency.

[0104] In addition, from the perspective of long-term stability, the ECSA of Example 1 can still be maintained at 42.08m after 30,000 CV cycles. 2 / g, with a decay rate of 25.5%. The high initial ECSA provides a "buffer space" for the catalyst's long-term stable operation. Even if active sites are lost after multiple cycles, the remaining effective active sites can still maintain a certain level of catalytic performance, extending the catalyst's actual service life.

[0105] In summary, 56.5m 2The electrochemical surface area (ECSA) of 1000 nm / g is not only a direct proof of the excellent platinum dispersion in the structure of the platinum-carbon catalyst PT50 in Example 1, but also the core foundation of its comprehensive leading position in catalytic activity, precious metal utilization and long-term stability, laying a key advantage for the practical application of this catalyst in fuel cells, water electrolysis and other fields.

[0106] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been presented as a preferred embodiment, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a functional catalyst for water electrolysis, characterized in that: The following steps are involved: The conductive carbon black is calcined, ball-milled, acid-washed, filtered, and dried to obtain a carbon support; The alkaline solution, chloroplatinic acid solution and carbon support slurry are fully mixed and dispersed uniformly to obtain a platinum-carbon precursor slurry; The platinum-carbon precursor slurry is vacuum treated, and the slurry needs to be stirred during the treatment process; Transferring the above system to a reaction device to carry out the reaction; After the reaction is completed, the solution is filtered and dried to obtain the water electrolysis functional catalyst.

2. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The conductive carbon black is one or more of porous carbon black, carbon nanotubes, mesoporous carbon, and carbon nanofibers.

3. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The mixed acid solution is any one of nitric acid, a mixed solution of nitric acid and sulfuric acid, and a mixed solution of nitric acid, sulfuric acid and hydrochloric acid.

4. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The alkaline solution is one of sodium bicarbonate, potassium hydroxide, sodium hydroxide, and calcium hydroxide solution, with a mass fraction of 5-15%.

5. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The carbon carrier slurry is a mixture of the treated carrier and one or more solutions of water, ethanol, isopropanol, n-propanol, ethylene glycol, and glycerol, and the mass fraction of the carbon carrier is 0.3-1.0%.

6. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: In the chloroplatinic acid solution, the mass fraction of chloroplatinic acid is 1-2%.

7. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The vacuum device is one of a vacuum generator, an oil-free diaphragm vacuum pump, a water ring pump, a sputtering ion pump and a cryogenic pump.

8. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The conductive carbon black is calcined by heating it to 1500-2000° C. in a nitrogen protective atmosphere and keeping the temperature for 60-180 minutes.

9. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The mass ratio of the alkaline solution, the chloroplatinic acid solution and the carbon support slurry is 1:9.9:14.

94.

10. The method for preparing a water electrolysis functional catalyst according to claim 1, characterized in that: The reaction system was heated to 90-130°C and kept at this temperature for 30-180 minutes before the heating was terminated.

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