Preparation method of platinum-carbon catalyst with adjustable size

Abstract

The invention relates to the technical field of catalyst preparation, in particular to a preparation method of a platinum-carbon catalyst with an adjustable size, which comprises the following steps: uniformly stirring and mixing an ethylene glycol solution containing H2O and an ethylene glycol solution containing potassium chloroplatinate, heating and reacting under the protection of inert gas, and cooling to room temperature after the reaction is completed; and adding a carbon carrier material into the reaction liquid, uniformly stirring, washing with water, and drying to obtain the platinum-carbon catalyst. In the invention, the polarity, viscosity and dielectric constant of an ethylene glycol solution can be changed by adding water into ethylene glycol, and the change of the properties can influence the reduction kinetics of metal ions and the nucleation growth process of particles. Therefore, under the action of the ethylene glycol reducing agent, the effect of regulating and controlling the particle size of the metal particles can be achieved only by relying on water, the method has the advantages of being simple and green and has wide application prospects, and the prepared platinum-carbon metal nano-catalyst is clean and free of pollution.

Description

Technical Field

[0001] The invention relates to the technical field of catalyst preparation, and in particular to a method for preparing a size-adjustable platinum-carbon catalyst. Background Art

[0002] In recent years, with the rapid development of electrocatalysts, the efficiency of electrocatalytic reactions has been significantly improved. Adjusting the size of electrocatalysts to achieve better electrochemical performance while reducing production costs is an effective way to improve the efficiency of electrocatalytic reactions.

[0003] Reducing the size of catalyst particles can significantly increase the specific surface area of ​​the catalyst per unit mass or volume, thereby providing more active sites, promoting the electrochemical reaction, and changing its electronic structure, thereby affecting the catalytic activity and selectivity. On a microscopic scale, small-sized catalyst particles can shorten the distance for reactants to diffuse to active sites and accelerate the charge transfer process, which is particularly beneficial for fast electrochemical reactions. Therefore, nanocatalysts with high specific surface areas have been widely used in advanced electrochemical devices such as fuel cells. By precisely controlling the size of the catalyst, its electrocatalytic performance can be optimized, thereby promoting the advancement of electrochemical technology in the fields of energy and environment.

[0004] A common method for controlling particle size in the ethylene glycol reduction method is to regulate the amount of alkali added. By regulating the concentration of the metal precursor solution and the concentration of the alkali, the size of the metal particles can be accurately controlled. For example, Chinese invention patent CN201510160273.7 discloses a method for preparing a platinum-carbon catalyst, which mainly regulates the size of the platinum-carbon catalyst particles based on the amount of sodium hydroxide and the amount of solvent ethanol, ethylene glycol, glycerol or n-octanol. However, in this method, metal particles are prone to agglomeration to form larger particle clusters, which not only reduces the specific surface area of ​​the catalyst, but also affects its catalytic activity and stability. In order to avoid particle agglomeration, it is usually necessary to add a surfactant or use other dispersion techniques to stabilize the particles.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The object of the present invention is to provide a method for preparing a size-adjustable platinum-carbon catalyst, which can achieve the regulation of the particle size of platinum nanoparticles and platinum-carbon nanoparticles by regulating the amount of water added.

[0007] The present invention provides a method for preparing a size-adjustable platinum-carbon catalyst, comprising the following steps:

[0008] The ethylene glycol solution containing H2O and the ethylene glycol solution containing potassium chloroplatinate are stirred and mixed evenly, and then heated to react under the protection of inert gas. After the reaction is completed, the mixture is cooled to room temperature. The carbon carrier material is added to the reaction solution and stirred evenly, and then the mixture is washed with water and dried to obtain a platinum-carbon catalyst.

[0009] In the preparation method of the size-adjustable platinum-carbon catalyst of the present invention, first, after the ethylene glycol solution containing H2O and the ethylene glycol solution containing potassium chloroplatinate are stirred and mixed uniformly, they are heated and reacted under the protection of inert gas, and the particle size of the platinum nanoparticles can be controlled by adjusting the amount of water added. Then, a certain amount of carbon carrier material is added to the reaction solution and stirred thoroughly to obtain a platinum-carbon catalyst of the corresponding particle size. In the present invention, water can not only adjust the reducing ability and reduction rate of ethylene glycol, but also effectively prevent the platinum nanoparticles from further growing or agglomerating by forming a protective layer on the surface of the platinum nanoparticles or by its interaction with the platinum nanoparticles, thereby maintaining a smaller particle size. In addition, water can also be used as a dispersant to promote the uniform distribution of platinum particles on the carbon carrier and reduce large particles and agglomeration. Therefore, the present invention can achieve the effect of regulating the particle size of metal particles by relying solely on water under the action of the ethylene glycol reducing agent.

[0010] As a preferred embodiment of the present technical solution, the concentration of the ethylene glycol solution containing H2O is 0.1-5g / mL in terms of the mass concentration of H2O. In actual use, the ethylene glycol solution containing H2O of appropriate concentration can be selected according to the particle size of the desired platinum particles or platinum carbon catalyst. Specifically, there is an optimal range for the amount of water added, within which the particle size of the Pt particles will decrease, but when the amount of water added is too large, the particle size will increase instead. If the proportion of water is too high and the concentration of ethylene glycol is reduced, the stability around the Pt nanoparticles may be reduced, and aggregation between particles cannot be effectively prevented.

[0011] As a preferred embodiment of the present technical solution, the concentration of the ethylene glycol solution containing potassium chloroplatinate is 0.01-0.05 g / mL in terms of the mass concentration of potassium chloroplatinate. In the ethylene glycol solution containing potassium chloroplatinate, ethylene glycol is both a solvent and a reducing agent, and water can not only adjust the reducing ability and reduction rate of ethylene glycol, but also effectively prevent the platinum nanoparticles from further growing or agglomerating by forming a protective layer on the surface of the platinum nanoparticles or by its interaction with the platinum nanoparticles, thereby maintaining a smaller particle size. Therefore, the present invention can achieve controllable particle size of platinum particles or platinum-carbon catalysts by regulating the amount of ethylene glycol and water.

[0012] As a preferred embodiment of the present technical solution, after the ethylene glycol solution containing H2O and the ethylene glycol solution containing potassium chloroplatinate are stirred and mixed evenly, the mixture is heated to 150-200°C under the protection of an inert atmosphere and maintained for 1-3 hours.

[0013] As a preferred embodiment of the present technical solution, the inert gas used in the present invention includes any one of nitrogen and argon, and the flow rate of the inert gas is preferably 100-150 mL / min.

[0014] As a preferred embodiment of the present technical solution, during the entire reaction process and cooling process, in order to improve the reaction efficiency and prevent the platinum nanoparticles from further growing or agglomerating, the stirring speed can be kept at 600-800 rpm at all times.

[0015] As a preferred embodiment of the present technical solution, the carbon support material includes any one or more of activated carbon, conductive carbon black, graphene, carbon nanotubes and mesoporous carbon. Specifically, the amount of the required carbon support material can be calculated according to different platinum loadings, and then the weighed carbon support material is added to the reaction solution and stirred thoroughly.

[0016] As a preferred embodiment of the present technical solution, deionized water or ultrapure water can be generally used for washing to ensure that impurities such as chloride ions and nitrate ions on the catalyst surface can be effectively removed. Specifically, centrifugal separation, filtration or soaking can be used for washing. Centrifugation and filtration can remove the washing liquid quickly, but care should be taken to avoid catalyst loss; soaking is more gentle, but takes longer time. The specific number of washing times can be determined according to the preparation method of the catalyst and the impurity content, and generally 10-20 times can be selected.

[0017] As a preferred embodiment of the present technical solution, during the drying, the temperature is controlled at 60-120°C. The specific temperature depends on the heat resistance of the catalyst and the required drying speed, and the drying time varies with the initial humidity of the catalyst and the drying temperature. Generally, it is necessary to dry to constant weight, and the time can be controlled at 10-24h.

[0018] As a preferred embodiment of the present technical solution, according to the preparation method of the present invention, a platinum-carbon catalyst with a particle size of 2-4 nm can be prepared.

[0019] The preparation method of the size-adjustable platinum-carbon catalyst of the present invention has at least the following beneficial effects: in the preparation method of the size-adjustable platinum-carbon catalyst of the present invention, first, after the ethylene glycol solution containing H2O and the ethylene glycol solution containing potassium chloroplatinate are stirred and mixed uniformly, they are heated and reacted under the protection of inert gas, and the particle size of the platinum nanoparticles can be controlled by adjusting the amount of water added. Then, after a certain amount of carbon carrier material is added to the reaction solution and fully stirred uniformly, a platinum-carbon catalyst of the corresponding particle size can be obtained. In the present invention, adding water to ethylene glycol can also change the polarity, viscosity and dielectric constant of the ethylene glycol solution, and the change of these properties will affect the reduction kinetics of metal ions and the nucleation growth process of particles. Specifically, water can not only adjust the reducing ability and reduction rate of ethylene glycol, but also effectively prevent the platinum nanoparticles from further growing or agglomerating by forming a protective layer on the surface of the platinum nanoparticles or by its interaction with the platinum nanoparticles, thereby maintaining a smaller particle size. In addition, water can also be used as a dispersant to promote the uniform distribution of platinum particles on the carbon carrier and reduce large particles and agglomeration. The amount of water added has an optimal range, within which the particle size of the Pt particles will decrease, but when the amount of water added is too large, the particle size will increase instead. If the proportion of water is too high, the concentration of ethylene glycol will decrease, which may lead to a decrease in the stability around the Pt nanoparticles and fail to effectively prevent the aggregation between particles. Therefore, the present invention can achieve the effect of regulating the particle size of metal particles only by relying on water. This method has a wide range of application prospects due to its simple and green advantages, and the prepared platinum carbon metal nanocatalyst is clean and pollution-free. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 The transmission electron microscope image and particle size distribution statistics of the material 20% Pt-10H2O-C prepared in Example 1 of the present invention;

[0022] Figure 2 The transmission electron microscope image and particle size distribution statistics of the material 20% Pt-20H2O-C prepared in Example 2 of the present invention;

[0023] Figure 3 The transmission electron microscope image and particle size distribution statistical diagram of the material 20% Pt-30H2O-C prepared in Example 3 of the present invention;

[0024] Figure 4The transmission electron microscope image and particle size distribution statistics of the material 20% Pt-5H2O-C prepared in Example 4 of the present invention;

[0025] Figure 5 The transmission electron microscope image and particle size distribution statistical graph of the material 20% Pt-NaOH-C-1 prepared in comparative example 1 of the present invention;

[0026] Figure 6 The transmission electron microscope image and particle size distribution statistics of the material 20% Pt-NaOH-C-2 prepared in Comparative Example 2 of the present invention;

[0027] Figure 7 The transmission electron microscope image and particle size distribution statistics of the material 20% Pt-NaOH-C-3 prepared in Comparative Example 3 of the present invention. DETAILED DESCRIPTION

[0028] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0029] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form also includes the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this description, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0030] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] Example 1

[0032] S1. Weigh 10 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 0.4 g / mL; weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 120 mL min -1In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0033] S2. Add 0.84 g of commercial carbon black into the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-10H2O-C catalyst.

[0034] Example 2

[0035] S1. Weigh 20 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 0.8 g / mL; weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 120 mL min -1 In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0036] S2. Add 0.84 g of commercial carbon black into the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-20H2O-C catalyst.

[0037] Example 3

[0038] S1. Weigh 30 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 1.2 g / mL; weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 120 mL min -1 In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0039] S2. Add 0.84 g of commercial carbon black into the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-30H2O-C catalyst.

[0040] Example 4

[0041] S1. Weigh 5 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 0.2 g / mL; weigh 1.0 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.04 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 150 mL min -1 In an argon atmosphere, the temperature was raised to 200° C. and kept constant at that temperature for 2 hours. During the heating process, the stirring speed was kept at 700 rpm. The stirring speed was kept constant until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0042] S2. Add 0.84 g of activated carbon to the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-5H2O-C catalyst.

[0043] Example 5

[0044] S1. Weigh 15 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 0.6 g / mL; weigh 0.3 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.01 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 100 mL min -1 In an argon atmosphere, the temperature was raised to 180° C. and kept constant at that temperature for 3 hours. During the heating process, the stirring speed was kept at 600 rpm. The stirring speed was kept constant until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0045] S2. Add 0.84 g of graphene to the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-15H2O-C catalyst.

[0046] Example 6

[0047] S1. Weigh 25 g of H2O and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing H2O with a mass concentration of 1 g / mL; weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL; pour the ethylene glycol solution containing H2O and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly; at a flow rate of 140 mL min-1 In an argon atmosphere, the temperature was raised to 170° C. and kept constant at that temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept constant until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0048] S2. Add 0.84 g of commercial carbon black into the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-25H2O-C catalyst.

[0049] Comparative Example 1

[0050] S1. Weigh 0.44 g of NaOH and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing NaOH with a mass concentration of 0.02 g / mL. Weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL. Pour the ethylene glycol solution containing NaOH and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until they are evenly mixed. Heat the mixture at a flow rate of 120 mL min -1 In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0051] S2. Add 0.84 g of commercial carbon black to the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-NaOH-C-1 catalyst.

[0052] Comparative Example 2

[0053] S1. Weigh 0.22 g of NaOH and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing NaOH with a mass concentration of 0.01 g / mL. Weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL. Pour the ethylene glycol solution containing NaOH and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until mixed evenly. Heat the mixture at a flow rate of 120 mL min -1 In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0054] S2. Add 0.84 g of commercial carbon black to the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-NaOH-C-2 catalyst.

[0055] Comparative Example 3

[0056] S1. Weigh 0.05 g of NaOH and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing NaOH with a mass concentration of 0.002 g / mL. Weigh 0.52 g of potassium chloroplatinate and dissolve it in 25 mL of ethylene glycol, and stir it evenly to obtain an ethylene glycol solution containing potassium chloroplatinate with a mass concentration of 0.02 g / mL. Pour the ethylene glycol solution containing NaOH and the ethylene glycol solution containing chloroplatinic acid into a three-necked flask together, stir until they are evenly mixed. Heat the mixture at a flow rate of 120 mL min -1 In an argon atmosphere, the temperature was raised to 160° C. and kept at a constant temperature for 3 hours. During the heating process, the stirring speed was kept at 800 rpm. The stirring speed was kept until the reaction liquid was cooled to room temperature to obtain a Pt sol.

[0057] S2. Add 0.84 g of commercial carbon black to the Pt sol, stir thoroughly for 24 hours, wash 10 times by centrifugation with deionized water, and dry to obtain a 20% Pt-NaOH-C-3 catalyst.

[0058] Figure 1-7 The transmission electron microscope images and particle size distribution statistics of the platinum carbon catalysts prepared in Examples 1-4 and Comparative Examples 1-3 are shown respectively.

[0059] Depend on Figure 1-7 It can be seen that with the increase of H2O concentration in the H2O-containing ethylene glycol solution, the particle size of the prepared platinum carbon catalyst first decreases and then increases; with the increase of NaOH concentration in the NaOH-containing ethylene glycol solution, the particle size of the prepared platinum carbon catalyst gradually decreases. This shows that just as the concentration of the metal precursor solution and the concentration of the alkali can be precisely controlled to control the size of the metal particles, the particle size of the nanoparticles and platinum carbon nanoparticles can also be regulated by regulating the amount of water added. However, compared with the method of regulating the alkali concentration, the use of water regulation can not only reduce the use of alkali, but also the prepared platinum carbon catalyst has better dispersibility, avoiding the problem of adding surfactants or using other dispersion techniques to stabilize the particles in the alkali regulation technology.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing a size-adjustable platinum-carbon catalyst, It is characterized in that The following steps are involved: Will contain H 2 The ethylene glycol solution containing O and the ethylene glycol solution containing potassium chloroplatinate are stirred and mixed evenly, and then heated to react under the protection of inert gas. After the reaction is completed, it is cooled to room temperature; the carbon carrier material is added to the reaction solution and stirred evenly, and then washed with water and dried to obtain a platinum carbon catalyst.

2. The preparation method according to claim 1, It is characterized in that The H-containing 2 The concentration of ethylene glycol solution in H 2 The mass concentration of O is 0.1-5 g / mL.

3. The preparation method according to claim 1, It is characterized in that The concentration of the ethylene glycol solution containing potassium chloroplatinate is 0.01-0.05 g / mL based on the mass concentration of potassium chloroplatinate.

4. The preparation method according to claim 1, It is characterized in that During the heating reaction, the temperature is controlled at 150-200° C. and the time is 1-3 hours.

5. The preparation method according to claim 1, It is characterized in that The flow rate of the inert gas is 100-150 mL / min.

6. The preparation method according to claim 1, It is characterized in that During the reaction and cooling process, the stirring speed was maintained at 600-800 rpm.

7. The preparation method according to claim 1, It is characterized in that The carbon support material includes any one or more of activated carbon, conductive carbon black, graphene, carbon nanotubes and mesoporous carbon.

8. The preparation method according to claim 1, It is characterized in that The number of times of water washing is 10-20 times.

9. The preparation method according to claim 1, It is characterized in that During the drying, the temperature is controlled at 60-120° C. and the time is 10-24 hours.

10. The preparation method according to claim 1, It is characterized in that The particle size of the platinum carbon catalyst is 2-4 nm.

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