Platinum-carbon catalyst, preparation method and application thereof, and hydrogen fuel cell

Abstract

The present invention discloses a platinum-carbon catalyst, a preparation method and an application thereof. The present invention also discloses a hydrogen fuel cell using the platinum-carbon catalyst. The platinum-carbon catalyst contains a carbonaceous carrier and metal platinum particles loaded on the carbonaceous carrier. In the platinum-carbon catalyst, the contact angle between the platinum nanoparticles and the carbon carrier is less than 50°. The preparation method comprises dispersing the carbonaceous material, the platinum precursor, the complexing agent and the dispersion medium with ultrasound, adjusting the pH value and reducing them with a reducing agent containing polyvinyl pyrrolidone and formic acid. The platinum-carbon catalyst according to the present invention has improved structural dispersibility and shows improved electrochemical catalytic activity and stability. According to the preparation method of the platinum-carbon catalyst of the present invention, the preparation process is simple, can effectively improve the interaction between the metal platinum particles and the carrier, improve the dispersion of the metal platinum particles on the carrier, and improve the electrochemical catalytic activity and stability of the prepared platinum-carbon catalyst.

Description

Technical Field

[0001] The present invention relates to a platinum-carbon catalyst and a preparation method and application thereof, and also relates to a hydrogen fuel cell using the platinum-carbon catalyst. Background Art

[0002] Due to the increasing consumption of fossil energy and the aggravation of environmental pollution, the high-efficiency, pollution-free, zero-carbon emission proton exchange membrane fuel cell technology has made great progress. However, at present, the development of the entire fuel cell technology is still in its infancy, and further development is still subject to the following technical constraints: high cost, low lifespan and limited energy density. Among them, the cathode oxygen reduction reaction (ORR) kinetics are slow, and its exchange current density is around 10 -6 A / cm 2 , which is far less than the hydrogen exchange current density of the anode. The existence of polarization resistance makes the actual battery potential far lower than the theoretical value. The most effective catalyst for the oxygen reduction reaction is the precious metal platinum, whose cost accounts for about 40% of the total cost of the fuel cell. After years of research, it has been found that the attenuation of catalyst catalytic activity is one of the main reasons for the degradation of fuel cell performance. Therefore, the development of high-performance and durable oxygen reduction reaction electrode catalysts is of great significance to accelerating the commercialization of fuel cells.

[0003] Currently, there are many methods for preparing carbon-supported platinum catalysts, such as liquid-phase reduction, gas-phase reduction, colloid, vapor deposition, and microwave methods. Each preparation method has its own advantages and disadvantages. For example, the colloid, vapor deposition, and microwave methods can produce highly dispersed platinum-based catalysts, but these three methods are expensive and have many problems during the scale-up process, making them difficult to scale up. Gas-phase reduction methods, such as hydrogen reduction, have the advantage of enabling a tighter bond between platinum and the carbon carrier, resulting in good stability. However, their disadvantage is that it is difficult to control the morphology of the catalyst, and the platinum loading is often below 40% by weight, making it difficult to increase. This limits the universality of platinum-based catalyst processes. Conventional liquid-phase reduction methods, such as ethylene glycol high-temperature reduction and organic acid reduction, have the advantage of being simple and easy to scale up in pilot-scale, but their disadvantages are poor structural dispersion and weak binding between platinum nanoparticles and the carrier.

[0004] Therefore, it is particularly important to develop a synthesis process that is easy to achieve mass production and can synthesize catalysts with excellent activity and stability. Summary of the Invention

[0005] The object of the present invention is to provide a platinum-carbon catalyst and a preparation method thereof, wherein the platinum-carbon catalyst has improved structural dispersion and catalytic activity, and the preparation method is easy to realize batch production.

[0006] According to a first aspect of the present invention, the present invention provides a platinum-carbon catalyst comprising a carbonaceous carrier and platinum nanoparticles supported on the carbonaceous carrier, wherein the contact angle between the platinum nanoparticles and the carbon carrier in the platinum-carbon catalyst is less than 50°.

[0007] According to a second aspect of the present invention, the present invention provides a method for preparing a platinum-carbon catalyst, the method comprising the following steps:

[0008] S1. Dispersing a carbonaceous material, a platinum precursor, a complexing agent, and a dispersion medium using ultrasound to obtain a first dispersion, wherein the complexing agent is one or more of a water-soluble salt of a dicarboxylic acid and a water-soluble salt of a polycarboxylic acid, and the dispersion medium is glycerol and water;

[0009] S2. adjusting the pH value of the first dispersion to 11-14 to obtain a second dispersion;

[0010] S3. Adding a reducing agent to the second dispersion, allowing the reducing agent to contact the platinum precursor in the second dispersion to perform a reduction reaction, wherein the reducing agent contains polyvinyl pyrrolidone and formic acid, and the molar ratio of the reducing agent to the platinum precursor is 150-1000:1.

[0011] According to a third aspect of the present invention, the present invention provides a platinum-carbon catalyst prepared by the method described in the second aspect of the present invention.

[0012] According to a fourth aspect of the present invention, the present invention provides use of the platinum-carbon catalyst described in the first aspect or the third aspect of the present invention in a fuel cell.

[0013] According to a fifth aspect of the present invention, the present invention provides a hydrogen fuel cell, the anode and / or cathode of the hydrogen fuel cell contains the platinum-carbon catalyst described in the first aspect or the third aspect of the present invention.

[0014] The platinum-carbon catalyst according to the present invention has improved structural dispersibility and exhibits enhanced electrochemical catalytic activity and stability. The method for preparing the platinum-carbon catalyst according to the present invention has a simple preparation process and can effectively improve the interaction between the metal platinum particles and the support, increase the dispersion of the metal platinum particles on the support, and improve the electrochemical catalytic activity and stability of the prepared platinum-carbon catalyst. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram for explaining the contact angle between metallic platinum and the carbonaceous support in a platinum-carbon catalyst;

[0016] Figure 2 This is a spherical aberration electron microscope photograph used to illustrate the contact angle between metallic platinum and the carbonaceous support in the platinum-carbon catalyst prepared in Example 1;

[0017] Figure 3 This is a transmission electron microscope photograph of the platinum-carbon catalyst prepared in Example 1;

[0018] Figure 4 This is a transmission electron microscope photograph of the platinum-carbon catalyst prepared in Comparative Example 1;

[0019] Figure 5 These are the oxygen reduction (ORR) polarization curves of the platinum-carbon catalysts prepared in Example 1 and Comparative Example 1. DETAILED DESCRIPTION

[0020] The endpoints of the ranges and any values ​​disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoints of each range, the endpoints of each range and individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered to be specifically disclosed herein.

[0021] According to a first aspect of the present invention, the present invention provides a platinum-carbon catalyst comprising a carbonaceous support and metal platinum particles supported on the carbonaceous support.

[0022] According to the platinum-carbon catalyst of the present invention, the contact angle between the platinum nanoparticles and the carbon support is less than 50°, generally in the range of 30°-50°, indicating that in the platinum-carbon catalyst of the present invention, there is a strong interaction between the metal platinum particles and the carbon support.

[0023] In the present invention, the contact angle between the metal platinum particles and the carbonaceous support is specifically defined as follows: Figure 1 As shown, on a straight line L1 located at the edge of the carbon, this line is tangent to the platinum nanoparticles. At the tangent point, another straight line L2 is drawn that is tangent to the nanoparticles. The angle between straight lines L1 and L2 is the contact angle θ. The present invention uses a profile imaging method to measure the contact angle between the metal platinum particles and the carbonaceous support. The specific testing method is as follows: using a transmission electron microscope, eight non-overlapping, widely dispersed transmission electron microscope images of the catalyst particles are randomly selected on the test sample. For each image, all nanoparticles located at the edge of the carbon support are selected, and the contact angles of these metal platinum particles with the carbonaceous support are calculated.

[0024] According to the platinum-carbon catalyst of the present invention, the carbonaceous support is preferably conductive carbon black. Preferred examples of the conductive carbon black may include, but are not limited to, one or more of Vulcan XC72, Ketjen EC300J, Ketjen EC600J, Blackpearls 2000, and Blackpearls 3000. According to the platinum-carbon catalyst of the present invention, the specific surface area of ​​the carbonaceous support is preferably 200-2000 m 2 / g, more preferably 250-1500m 2 / g.

[0025] In the present invention, the specific surface area is measured using the BET (Brief Estimation of Surface Area and Pore Size) method.

[0026] According to the platinum-carbon catalyst of the present invention, based on the total amount of the platinum-carbon catalyst, the content of the platinum element can be 20-90 weight%, preferably 30-80 weight%, more preferably 40-75 weight%, and further preferably 40-70 weight%. The content of the carbonaceous carrier can be 10-80 weight%, preferably 20-70 weight%, more preferably 25-60 weight%, and further preferably 30-60 weight%. The carbonaceous carrier is calculated as carbon element.

[0027] In the present invention, the contents of platinum element and carbonaceous carrier in the platinum-carbon catalyst are determined by inductively coupled plasma spectroscopy (ICP).

[0028] The platinum-carbon catalyst according to the present invention has highly uniform platinum cluster particles. According to the platinum-carbon catalyst according to the present invention, the average particle size of the platinum nanoparticles in the platinum-carbon catalyst is in the range of 3-4 nm.

[0029] In the present invention, the average particle size of the platinum metal particles in the platinum-carbon catalyst is determined using transmission electron microscopy. The specific testing method involves randomly selecting eight non-overlapping, widely dispersed transmission electron micrographs of the catalyst particles on the test sample. The particle sizes of 50 catalyst platinum particles are statistically analyzed from each image (a total of 400 particles across the eight images), and the average particle size for each image is calculated.

[0030] The platinum carbon catalyst according to the present invention shows an improved electrochemical active area and electrochemical catalytic activity. The platinum carbon catalyst according to the present invention has a half-wave potential of 0.86 V or more, preferably 0.87 V or more, and more preferably 0.88 V or more. The platinum carbon catalyst according to the present invention has an electrochemical active area (ECSA) of 50 m 2 ·g -1 -Pt above (e.g. 50-65m 2 ·g -1 -Pt), preferably 55-60m 2 ·g -1-Pt.

[0031] According to a second aspect of the present invention, the present invention provides a method for preparing a platinum-carbon catalyst, the method comprising the following steps:

[0032] S1, dispersing the carbonaceous material, the platinum precursor, the complexing agent and the dispersion medium by ultrasonic wave to obtain a first dispersion;

[0033] S2. adjusting the pH value of the first dispersion to 11-14 to obtain a second dispersion;

[0034] S3. Adding a reducing agent to the second dispersion, and allowing the reducing agent to contact the platinum precursor in the second dispersion to perform a reduction reaction.

[0035] In step S1, the platinum precursor may be a platinum compound that can be reduced to metallic platinum by a reducing agent under reduction reaction conditions. According to the method of the present invention, the platinum precursor may be one or more selected from chloroplatinic acid, potassium chloroplatinate, and sodium chloroplatinate. Preferably, the platinum precursor is chloroplatinic acid.

[0036] In step S1, the complexing agent is one or more of a dicarboxylate and a polycarboxylate, for example, an alkali metal salt of a dicarboxylic acid, an ammonium salt of a dicarboxylic acid, an alkali metal salt of a polycarboxylic acid, or an ammonium salt of a polycarboxylic acid. The polycarboxylic acid refers to an organic compound containing three or more carboxyl groups in its molecular structure. In a preferred embodiment, the complexing agent is one or more of sodium citrate, sodium oxalate, sodium ethylenediaminetetraacetic acid, and sodium tartrate. More preferably, the complexing agent is sodium citrate. The amount of the complexing agent used can be selected based on the amount of the platinum precursor used. Preferably, the mass ratio of the platinum precursor to the complexing agent is 1:0.1-7. More preferably, the mass ratio of the platinum precursor to the complexing agent is 1:0.15-5. Further preferably, the mass ratio of the platinum precursor to the complexing agent is 1:0.2-3. Even more preferably, the mass ratio of the platinum precursor to the complexing agent is 1:0.25-1. Particularly preferably, the mass ratio of the platinum precursor to the complexing agent is 1:0.3-0.6.

[0037] In step S1, the dispersion medium is glycerol and water. According to the method of the present invention, using glycerol and water as the dispersion medium can effectively control the particle size and surface properties of the metal platinum particles in the prepared platinum-carbon catalyst, compared with using only water as the dispersion medium or only glycerol as the dispersion medium, so that the final prepared platinum-carbon catalyst shows an improved electrochemical active area and electrochemical catalytic activity. According to the method of the present invention, from the perspective of further improving the electrochemical catalytic activity and stability of the prepared platinum-carbon catalyst, in step S1, the volume ratio of glycerol to water is preferably 0.2-5:1, more preferably 0.3-3:1, further preferably 0.5-2:1, and even more preferably 0.8-1.2:1. According to the method of the present invention, in step S1, the amount of the dispersion medium is such that the concentration of the platinum precursor relative to the dispersion medium is preferably 1-20 g / L, more preferably 2-10 g / L, further preferably 3-8 g / L, and even more preferably 3-5 g / L.

[0038] In step S1, the carbonaceous material is conductive carbon black. Preferred examples of the conductive carbon black may include, but are not limited to, one or more of Vulcan XC72, Ketjen EC300J, Ketjen EC600J, Blackpearls 2000, and Blackpearls 3000. According to the method of the present invention, the specific surface area of ​​the carbonaceous support is preferably 200-2000 m 2 / g, more preferably 250-1500m 2 / g.

[0039] According to the method of the present invention, in step S1, the carbonaceous material may be a carbonaceous material that has not been surface treated, a carbonaceous material that has been surface treated, or a combination of a carbonaceous material that has not been surface treated and a carbonaceous material that has been surface treated.

[0040] In one embodiment, the carbonaceous material is a surface-treated carbonaceous material. In this embodiment, the method according to the present invention further includes a step S0 of pretreating the carbonaceous material in step S1. In step S0, the carbonaceous material is sequentially subjected to solvent treatment, first oxidation treatment, second oxidation treatment and high-temperature treatment to obtain a pretreated carbonaceous material, and the pretreated carbonaceous material is used in step S1.

[0041] In the solvent treatment, the carbonaceous material is soaked in an organic solvent to obtain a carbonaceous material soaked in an organic solvent. The organic solvent is one or more selected from ketone solvents, preferably acetone. The soaking can be carried out at room temperature or at an elevated temperature. Preferably, the temperature of the organic solvent is 50-70°C. The duration of the soaking can be selected according to the soaking temperature. Generally, the soaking duration can be 5-24 hours. The amount of the organic solvent used is based on the ability to immerse the carbonaceous material. Generally, the volume ratio of the solvent to the carbonaceous material can be 1-3:1.

[0042] In the solvent treatment, after the soaking is completed, the solid phase and the liquid phase can be separated by conventional methods (such as filtration), and the obtained solid phase can be dried to obtain a solvent-treated carbonaceous material. The drying can be carried out at a temperature of 80-120°C, and the duration of the drying can be 5-15 hours, preferably 8-12 hours. The drying can be carried out under normal pressure or under reduced pressure.

[0043] In the first oxidation treatment, the carbonaceous material soaked in the organic solvent is contacted with a first oxidant to obtain a carbonaceous material subjected to the first oxidation treatment, wherein the first oxidant is one or more selected from hydrogen peroxide and an organic peroxide represented by formula (I):

[0044]

[0045] In formula I, R1 and R2 are each selected from H, C4-C 12 Alkyl, C6-C 12 Aryl, C7-C 12 Aralkyl and R1 and R2 are not H at the same time, and R3 is C4-C 12 Straight or branched alkyl or C6-C 12 of aromatic groups.

[0046] In the present invention, C4-C 12 Specific examples of the alkyl group may include, but are not limited to, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, neopentyl, isopentyl, tert-pentyl, hexyl (including various isomers of hexyl), cyclohexyl, octyl (including various isomers of octyl), nonyl (including various isomers of nonyl), decyl (including various isomers of decyl), undecyl (including various isomers of undecyl) and dodecyl (including various isomers of dodecyl).

[0047] In the present invention, C6-C 12 Specific examples of the aryl group may include, but are not limited to, phenyl, naphthyl, methylphenyl, and ethylphenyl.

[0048] In the present invention, C7-C 12 Specific examples of the aralkyl group may include, but are not limited to, phenylmethyl, phenylethyl, phenyl-n-propyl, phenyl-n-butyl, phenyl-t-butyl, phenylisopropyl, phenyl-n-pentyl, and phenyl-n-butyl.

[0049] Specific examples of the organic peroxide may include, but are not limited to, tert-butyl hydroperoxide, cumene hydroperoxide, ethylbenzene hydroperoxide, cyclohexyl hydroperoxide, dicumyl peroxide, dibenzoyl peroxide, di-tert-butyl peroxide, and dodecyl peroxide.

[0050] Preferably, the first oxidizing agent is hydrogen peroxide.

[0051] In the first oxidation treatment, the carbonaceous material soaked in an organic solvent is contacted with a first oxidant in a liquid phase in the presence of a liquid dispersion medium. The liquid dispersion medium can be water and / or a C1-C4 alcohol, preferably water. In a preferred embodiment, the first oxidant is dissolved in the liquid dispersion medium to form a first oxidant solution, and the first oxidant solution is contacted with the carbonaceous material soaked in the organic solvent. In this preferred embodiment, hydrogen peroxide is preferably used as the first oxidant solution. The concentration of hydrogen peroxide in the hydrogen peroxide can be 8-20% by weight.

[0052] In the first oxidation treatment, the contacting is preferably performed at a temperature of 50-70°C. The duration of the contacting can be selected based on the contacting temperature, and is preferably 5-12 hours. The amount of the first oxidant can be selected based on the amount of the carbonaceous material soaked in the organic solvent. Preferably, the mass ratio of the first oxidant to the carbonaceous material soaked in the organic solvent is 1-3:1.

[0053] In the first oxidation treatment, after the first oxidant treatment is completed, the solid phase and the liquid phase can be separated by conventional methods (such as filtration), and the obtained solid phase can be dried to obtain the carbonaceous material treated with the first oxidant. The drying can be carried out at a temperature of 80-120°C and the duration of the drying can be 5-15 hours, preferably 8-12 hours. The drying can be carried out under normal pressure or under reduced pressure.

[0054] In the second oxidation treatment, the carbonaceous material subjected to the first oxidation treatment is contacted with a second oxidant to obtain a carbonaceous material subjected to the second oxidation treatment, wherein the second oxidant is HNO3 and / or H2SO4. Preferably, the second oxidant is HNO3.

[0055] In the second oxidation treatment, the carbonaceous material subjected to the first oxidation treatment is contacted with a second oxidant in the presence of a liquid dispersion medium. The liquid dispersion medium may be water and / or a C1-C4 alcohol, preferably water. In a preferred embodiment, the second oxidant is dissolved in the liquid dispersion medium to form a second oxidant solution, which is then contacted with the carbonaceous material subjected to the first oxidation treatment. In this preferred embodiment, nitric acid is preferably used as the second oxidant solution. The concentration of the nitric acid may be 10-30% by weight.

[0056] In the second oxidation treatment, the contact is preferably performed at a temperature of 50-70° C. In the second oxidation treatment, the duration of the contact can be selected according to the contact temperature. Preferably, the duration of the contact can be 5-12 hours.

[0057] In the second oxidation treatment, after the second oxidant treatment is completed, the solid phase and the liquid phase can be separated by conventional methods (such as filtration), and the obtained solid phase can be dried to obtain the carbonaceous material treated with the second oxidant. The drying can be carried out at a temperature of 80-120°C and the duration of the drying can be 5-15 hours, preferably 8-12 hours. The drying can be carried out under normal pressure or under reduced pressure.

[0058] In the high-temperature treatment, the carbonaceous material that has undergone the second oxidation treatment is calcined at a temperature of 300-600°C in an inert atmosphere to obtain a pretreated carbonaceous material. The inert atmosphere can be an atmosphere formed by nitrogen and / or a zero-group gas, for example, an atmosphere formed by one or more of nitrogen, argon, and helium. The duration of the calcination can be selected based on the calcination temperature. Preferably, the calcination duration can be 5-24 hours, more preferably 6-12 hours.

[0059] According to the method of the present invention, in a more preferred embodiment, the carbonaceous material is a carbonaceous material that has not been subjected to surface modification treatment, and the surface modification treatment includes but is not limited to oxidation treatment, acid washing and high-temperature treatment, such as the surface treatment described above. It will be understood by those skilled in the art that, in this more preferred embodiment, the carbonaceous material can be washed using conventional methods in the art before being used in a platinum-carbon catalyst to remove impurities and contaminants attached to the surface of the carbonaceous material. According to this more preferred embodiment, the platinum-carbon catalyst prepared by the method of the present invention still shows improved electrochemical catalytic activity and stability, and the preparation method is simpler and more suitable for large-scale production.

[0060] According to the method of the present invention, in step S1, the carbonaceous material, the platinum precursor, the complexing agent, and the dispersion medium are dispersed using ultrasound, so that the carbonaceous material and the platinum precursor are fully mixed. Preferably, the power of the ultrasound is 100-1000W, preferably 100-500W. The duration of the ultrasonic dispersion can be 0.2-5 hours, preferably 0.5-3 hours, and more preferably 1-2 hours. The present invention is not particularly limited to the ultrasonic dispersion device, and dispersion can be performed in a common ultrasonic dispersion device.

[0061] According to the method of the present invention, in step S2, the pH value of the first dispersion obtained in step S1 is adjusted to 11-14 to obtain a second dispersion. From the perspective of further improving the electrochemical active area and electrochemical catalytic activity of the platinum-carbon catalyst prepared, in step S2, the pH value of the first dispersion obtained in step S1 is preferably adjusted to 12-13 to obtain a second dispersion. A pH regulator can be added to the first dispersion to adjust the pH value to 11-14 (preferably adjusted to 12-13). The pH regulator is preferably one or more of sodium carbonate, potassium carbonate, potassium hydroxide and sodium hydroxide, more preferably sodium carbonate and / or potassium carbonate. The pH regulator is preferably provided in the form of an aqueous solution, and the concentration of the aqueous solution can be conventionally selected and is not particularly limited.

[0062] According to the method of the present invention, in step S3, the reducing agent contains polyvinyl pyrrolidone and formic acid. In a preferred embodiment, in step S3, the reducing agent is polyvinyl pyrrolidone and formic acid. According to the method of the present invention, using polyvinyl pyrrolidone and formic acid as reducing agents, compared with using formic acid alone as a reducing agent or using polyvinyl pyrrolidone alone as a reducing agent, can effectively improve the electrochemical active area and electrochemical catalytic activity of the prepared platinum-carbon catalyst. The reason may be that: the combination of polyvinyl pyrrolidone and formic acid can achieve the simultaneous nucleation and loading of platinum, thereby effectively enhancing the interaction between the metal platinum particles and the carrier, improving the stability of the metal platinum particles on the carrier, and then improving the electrochemical active area and electrochemical catalytic activity of the platinum-carbon catalyst.

[0063] According to the method of the present invention, from the perspective of further improving the electrochemical catalytic activity and stability of the finally prepared platinum-carbon catalyst, the molar ratio of polyvinyl pyrrolidone to formic acid in the reducing agent of step S3 is preferably 1:1-5, more preferably 1:1-3.

[0064] According to the method of the present invention, in step S3, the reducing agent is preferably used in excess of the stoichiometric ratio. In step S3, the molar ratio of the reducing agent to the platinum precursor is 150-1000:1. From the perspective of further improving the electrochemical catalytic activity and stability of the finally prepared platinum-carbon catalyst and reducing costs, in step S3, the molar ratio of the reducing agent to the platinum precursor is preferably 160-800:1, more preferably 170-600:1, further preferably 180-500:1, further preferably 190-400:1, and particularly preferably 200-300:1, and the platinum precursor is calculated as platinum element.

[0065] According to the method of the present invention, step S3 can be carried out under conventional reduction reaction conditions. Preferably, in step S3, the reduction reaction is carried out at a temperature of 50-140°C. More preferably, in step S3, the reduction reaction is carried out at a temperature of 60-120°C. Further preferably, in step S3, the reduction reaction is carried out at a temperature of 70-100°C. Still further preferably, in step S3, the reduction reaction is carried out at a temperature of 80-90°C. In step S3, the duration of the reduction reaction can be selected according to the temperature at which the reduction reaction is carried out. Generally, in step S3, the duration of the reduction reaction can be 4-15 hours, preferably 5-13 hours, more preferably 8-12 hours. In step S3, the reduction reaction is carried out in an inert atmosphere, for example, it can be carried out in an atmosphere formed by nitrogen and / or group zero gas (such as argon and / or helium).

[0066] According to the method of the present invention, a conventional separation method can be used to separate the solid phase material from the reduction mixture obtained in step S3, and the separated solid phase material is washed with water and dried in turn to obtain a platinum carbon catalyst. Generally, the reduction mixture obtained in step S3 can be subjected to solid-liquid separation by a combination of one or more of filtration, centrifugation and sedimentation to obtain a solid phase material. The drying is preferably carried out at a temperature of 60-120°C, more preferably at a temperature of 80-110°C, and the duration of the drying can be 12-24 hours. The drying can be carried out at normal pressure or under conditions below atmospheric pressure.

[0067] The platinum-carbon catalyst prepared by the method of the present invention shows improved electrochemical activity and stability.

[0068] According to the third aspect of the present invention, the present invention provides a platinum-carbon catalyst prepared by the method described in the second aspect of the present invention.

[0069] According to the platinum-carbon catalyst described in the third aspect of the present invention, the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is less than 50°, generally in the range of 30°-50°, indicating that there is a strong interaction between the metallic platinum particles and the carbonaceous support in the platinum-carbon catalyst according to the present invention. The platinum-carbon catalyst described in the third aspect of the present invention has highly uniform platinum cluster particles, and the average particle size of the platinum nanoparticles in the platinum-carbon catalyst is in the range of 3-4 nm.

[0070] According to the third aspect of the present invention, the platinum-carbon catalyst has a half-wave potential of 0.86 V or more, preferably 0.87 V or more, and more preferably 0.88 V or more. According to the third aspect of the present invention, the platinum-carbon catalyst has an electrochemically active area (ECSA) of 50 m 2 ·g -1 -Pt above (e.g. 55-65m 2 ·g -1 -Pt), preferably 55-60m 2 ·g -1 -Pt.

[0071] The platinum-carbon catalyst according to the present invention is particularly suitable for use in fuel cells. According to a fourth aspect of the present invention, the present invention provides use of the platinum-carbon catalyst according to the first or third aspect of the present invention in a fuel cell.

[0072] According to a fifth aspect of the present invention, the present invention provides a hydrogen fuel cell, the anode and / or cathode of the hydrogen fuel cell contains the platinum-carbon catalyst described in the first aspect or the third aspect of the present invention.

[0073] The present invention is described in detail below with reference to the embodiments, but the scope of the present invention is not limited thereby.

[0074] In the following examples and comparative examples, the contents of platinum element and carbonaceous carrier in the platinum-carbon catalyst were determined by inductively coupled plasma spectroscopy (ICP).

[0075] In the following examples and comparative examples, transmission electron microscopy analysis was performed on a transmission electron microscope (TECNAI G2 F20) purchased from FEI Company. The sample preparation method was as follows: about 1 mg of the sample was dispersed in 60-80 wt% ethanol, ultrasonically dispersed for 10 minutes, a small amount of the dispersion was taken with a pipette, and dropped onto a copper mesh for electron microscopy testing. The copper mesh used was a microgrid or ultra-thin microgrid, and no ultra-thin carbon film or carbon support film was used.

[0076] In the following examples and comparative examples, the average particle size of the platinum metal particles in the platinum-carbon catalyst was measured using transmission electron microscopy. The specific testing method involved randomly selecting eight non-overlapping, widely dispersed transmission electron micrographs of the catalyst particles on the test sample. The particle size of 50 platinum catalyst particles was statistically analyzed from each image (a total of 400 images across the eight images), and the average particle size for each image was calculated.

[0077] In the following examples and comparative examples, the contact angle between the metal platinum particles and the carbonaceous support in the platinum-carbon catalyst was measured by transmission electron microscopy: Figure 1 As shown, on the straight line L1 where the edge area of ​​the carbon is located, this straight line is tangent to the platinum nanoparticles, and another straight line L2 is drawn tangent to the nanoparticles at the tangent point. The angle between the straight line L1 and the straight line L2 is the contact angle θ.

[0078] In the following examples and comparative examples, the specific surface area was measured using a specific surface area meter model JW-BK200 purchased from Beijing Jingwei Gaobo.

[0079] In the following examples and comparative examples, the electrochemical activity of the platinum-carbon catalyst was tested using a rotating disk test method. The catalyst was prepared into a slurry and drop-coated on a glassy carbon electrode with a diameter of 5 mm. The slurry was dried to ensure that the Pt loading on the electrode was between 18 and 22 μg / cm 2 The test conditions for the catalyst polarization curve are: 0.1M HClO4 solution, oxygen saturation, voltage scanning range of 0-1.0V vs RHE, scanning rate of 10mV / s, and rotating disk electrode speed of 1600r / min; the test conditions for the electrochemical active area are: 0.1M HClO4 solution, nitrogen saturation, voltage scanning range of 0-1.0V vs RHE, scanning rate of 50mV / s, and the hydrogen desorption peak area on the curve is integrated.

[0080] Among them, the calculation formula of the electrochemical active area (ECSA) of the platinum carbon catalyst is:

[0081]

[0082] Among them, S H is the peak area,

[0083] V is the scan rate, which is 0.05v / s,

[0084] M pt is the mass of Pt dropped on the glassy carbon electrode;

[0085] The mass specific activity, A / mg Pt ) is calculated as:

[0086]

[0087] Among them, i k is the kinetic current, in mA / cm 2 , which is calculated based on the KL equation, and the equation form is as follows:

[0088]

[0089] i L is the limiting diffusion current, which is directly read from the ORR curve;

[0090] m Pt is the amount of Pt loaded on the glassy carbon electrode, in mg Pt / cm 2 .

[0091] The following examples and comparative examples involve the following conductive carbon blacks:

[0092] (1) Conductive carbon black with the brand name Ketjen EC 300J was purchased from Lion Corporation of Japan. The particle diameter ranged from 50 nm to 100 nm and the specific surface area was 1400 m 2 / g;

[0093] (2) Conductive carbon black with the brand name Vulcan XC72, purchased from Cabot Corporation, USA, with a particle diameter ranging from 50 nm to 100 nm and a specific surface area of ​​260 m 2 / g.

[0094] Examples 1-7 are used to illustrate the platinum-carbon catalyst of the present invention, its preparation method and application.

[0095] Example 1

[0096] (1) 0.3 g of Ketjen EC300J conductive carbon black was added to 400 mL of a mixed solution of deionized water and glycerol (the volume ratio of deionized water to glycerol was 1:1). After mixing, 0.7 g of sodium citrate was added, followed by an aqueous solution of chloroplatinic acid (3.6 mmol of chloroplatinic acid). The resulting mixture was ultrasonically dispersed to form a first dispersion. The ultrasonic power was 100 W, and the ultrasonic dispersion time was 2 h.

[0097] (2) A sodium carbonate aqueous solution was added as a pH adjuster to the first dispersion to adjust the pH of the dispersion to 13, thereby obtaining a second dispersion.

[0098] (3) The third dispersion was heated to 80°C using a heater and stirred, and formic acid and polyvinyl pyrrolidone were added as reducing agents to conduct a reduction reaction. The molar ratio of the reducing agent to chloroplatinic acid was 200:1, and the molar ratio of formic acid to polyvinyl pyrrolidone in the reducing agent was 1:1. After the addition of the reducing agent, the heating conditions of the heater were maintained unchanged and the reaction was continued for 10 hours.

[0099] After the reaction was completed, the reduction reaction mixture was filtered, the solid phase was collected, and the solid phase was washed with deionized water until the washing liquid was neutral. The washed solid phase was vacuum dried at 100°C for 12 hours to obtain 1g of the platinum-carbon catalyst according to the present invention. The mass content of platinum in the platinum-carbon catalyst was determined to be 69%. The contact angle between the platinum nanoparticles and the carbon support was determined to be in the range of 30°-50°, and the average particle size of the platinum nanoparticles was 3-4nm. The electrochemical performance of the prepared platinum-carbon catalyst was measured, and the experimental results are listed in Table 1.

[0100] Example 2 (including Example 2a, Example 2b and Example 2c)

[0101] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that different pH adjusters were used in step (2). In Example 2a, potassium carbonate was used as the pH adjuster; in Example 2b, sodium bicarbonate was used as the pH adjuster; and in Example 2c, sodium hydroxide was used as the pH adjuster. The electrochemical properties of the prepared platinum-carbon catalysts were measured, and the experimental results are listed in Table 1.

[0102] The platinum-carbon catalyst prepared in Example 2a has a platinum content of 70% by mass. Measurements show that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 50°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0103] The platinum-carbon catalyst prepared in Example 2b has a platinum content of 70% by mass. Measurements show that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 45°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0104] The mass content of platinum in the platinum-carbon catalyst prepared in Example 2c is 69%. It has been determined that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 45°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0105] Example 3 (including Example 3a and Example 3b)

[0106] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that the pH value in step (2) was different. In Example 3a, the pH value was adjusted to 11; in Example 3b, the pH value was adjusted to 12. The electrochemical properties of the prepared platinum-carbon catalysts were measured, and the experimental results are listed in Table 1.

[0107] The platinum-carbon catalyst prepared in Example 3a has a platinum content of 69.5% by mass. Measurements show that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 45°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0108] The mass content of platinum in the platinum-carbon catalyst prepared in Example 3b is 69.5%. It has been determined that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 45°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0109] Comparative Example 1 (including Comparative Example 1a, Comparative Example 1b and Comparative Example 1c)

[0110] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that the pH value in step (2) was different: in Comparative Example 1a, the pH value was adjusted to 8; in Comparative Example 1b, the pH value was adjusted to 9; and in Comparative Example 1c, the pH value was adjusted to 10. The platinum-carbon catalysts prepared in Comparative Examples 1a, 1b, and 1c had a platinum content of 70% by mass. The average particle size of the platinum nanoparticles in the platinum-carbon catalysts was determined to be within the range of 3-4.5 nm. The electrochemical properties of the prepared platinum-carbon catalysts were measured, and the experimental results are listed in Table 1.

[0111] Example 4

[0112] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that the reaction time in step (3) was 12 h. The electrochemical properties of the prepared platinum-carbon catalyst were measured, and the experimental results are listed in Table 1. The mass content of platinum in the prepared platinum-carbon catalyst was 69.3%. It was determined that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst was in the range of 30° to 50°, and the average particle size of the platinum nanoparticles was in the range of 3-4 nm.

[0113] Comparative Example 2

[0114] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that glycerol and sodium citrate were not used in step (1), and the dispersion medium was 400 mL of deionized water. The mass content of platinum in the prepared platinum-carbon catalyst was 69%. After measurement, the contact angle of the platinum nanoparticles with the carbon support was within the range of 0° to 180°, with no obvious distribution pattern, and the average particle size of the platinum nanoparticles was within the range of 4.5-6.5 nm. The electrochemical performance of the prepared platinum-carbon catalyst was measured, and the experimental results are listed in Table 1.

[0115] Comparative Example 3

[0116] The platinum carbon catalyst was prepared by the same method as in Example 1, except that glycerol was not used in step (1), and the dispersion medium was 400 mL of deionized water. The mass content of platinum in the prepared platinum carbon catalyst was 69%. After measurement, the contact angle of the platinum nanoparticles with the carbon support was within the range of 0 ° to 180 °, with no obvious distribution pattern, and the average particle size of the platinum nanoparticles was within the range of 4.5-7.0 nm. The electrochemical performance of the prepared platinum carbon catalyst was measured, and the experimental results are listed in Table 1.

[0117] Comparative Example 4

[0118] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that sodium citrate was not used in step (1). The mass content of platinum in the prepared platinum-carbon catalyst was 70%. The contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst was determined to be in the range of 0° to 180°, with no obvious distribution pattern. The average particle size of the platinum nanoparticles was in the range of 4.5-7.0 nm. The electrochemical properties of the prepared platinum-carbon catalyst were measured, and the experimental results are listed in Table 1.

[0119] Comparative Example 5

[0120] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that, in step (3), the amount of reducing agent was kept constant, but formic acid was not used, and formic acid was replaced by an equimolar amount of polyvinyl pyrrolidone. The mass content of platinum in the prepared platinum-carbon catalyst was 69.5%. After measurement, the contact angle of the platinum nanoparticles with the carbon support in the platinum-carbon catalyst was within the range of 0° to 180°, with no obvious distribution pattern, and the average particle size of the platinum nanoparticles was within the range of 4.5-7.0nm. The electrochemical properties of the prepared platinum-carbon catalyst were measured, and the experimental results are listed in Table 1.

[0121] Comparative Example 6

[0122] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that, in step (3), the amount of reducing agent was kept constant, but polyvinyl pyrrolidone was not used, and polyvinyl pyrrolidone was replaced by an equimolar amount of formic acid. The mass content of platinum in the prepared platinum-carbon catalyst was 70.1%. After measurement, the contact angle of the platinum nanoparticles with the carbon support in the platinum-carbon catalyst was within the range of 0° to 180°, with no obvious distribution pattern, and the average particle size of the platinum nanoparticles was within the range of 4.5-7.5nm. The electrochemical properties of the prepared platinum-carbon catalyst were measured, and the experimental results are listed in Table 1.

[0123] Comparative Example 7

[0124] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that in step (3), polyvinyl pyrrolidone was replaced with an equimolar amount of citric acid. The mass content of platinum in the prepared platinum-carbon catalyst was 69%. The contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst was determined to be in the range of 0° to 180°, with no obvious distribution pattern. The average particle size of the platinum nanoparticles was in the range of 4.5-7.5 nm. The electrochemical properties of the prepared platinum-carbon catalyst were measured, and the experimental results are listed in Table 1.

[0125] Example 5 (including Example 5a and Example 5b)

[0126] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that in step (3), the ratio of polyvinyl pyrrolidone to formic acid was varied. In Example 5a, the molar ratio of formic acid to polyvinyl pyrrolidone was 2:1; and in Example 5b, the molar ratio of formic acid to polyvinyl pyrrolidone was 3:1. The electrochemical properties of the prepared platinum-carbon catalysts were measured, and the experimental results are listed in Table 1.

[0127] The platinum-carbon catalyst prepared in Example 5a has a platinum content of 69% by mass. Measurements show that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 50°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0128] The platinum-carbon catalyst prepared in Example 5b has a platinum content of 70% by mass. Measurements show that the contact angle between the platinum nanoparticles and the carbon support in the platinum-carbon catalyst is in the range of 30° to 50°, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0129] The electrochemical performance of the prepared platinum-carbon catalyst was measured, and the experimental results are listed in Table 1.

[0130] Comparative Example 8 (including Comparative Example 8a and Comparative Example 8b)

[0131] A platinum-carbon catalyst was prepared using the same method as in Example 1, except that in step (3), the molar ratio of formic acid to polyvinyl pyrrolidone in the reducing agent remained unchanged, while the amount of the reducing agent was varied. In Comparative Example 8a, the molar ratio of the reducing agent to chloroplatinic acid was 100:1; and in Comparative Example 8b, the molar ratio of the reducing agent to chloroplatinic acid was 50:1. The platinum content of the platinum-carbon catalyst prepared in Comparative Example 8a was 69% by mass, while the platinum content of the platinum-carbon catalyst prepared in Comparative Example 8b was 70% by mass. The electrochemical properties of the prepared platinum-carbon catalysts were measured, and the experimental results are listed in Table 1.

[0132] Example 6

[0133] The platinum-carbon catalyst was prepared by the same method as in Example 1, except that a pretreatment step of the conductive carbon black was performed before step (1), and the conductive carbon black pretreated by the following method was used in step (1):

[0134] (1) 0.3 g of Ketjen EC 300J conductive carbon black was soaked in acetone (analytical grade) at 60°C for 24 h, where the mass ratio of acetone to carbon black was 2:1. After soaking, the solid phase was filtered and dried at 100°C for 6 h to obtain acetone-soaked carbon black.

[0135] (2) The carbon black soaked in acetone was mixed with 8% hydrogen peroxide (the mass ratio of hydrogen peroxide to carbon black was 2:1) and reacted at 60°C for 12 hours. After the reaction was completed, the reaction mixture was filtered and the obtained solid phase was dried at 100°C for 12 hours to obtain carbon black that had undergone the first oxidation treatment.

[0136] (3) The carbon black subjected to the first oxidation treatment was mixed with a 30% nitric acid aqueous solution (the mass ratio of HNO3 to carbon black was 2:1) and reacted at 60°C for 12 hours. After the reaction was completed, the reaction mixture was filtered and the obtained solid phase was dried at 100°C for 8 hours to obtain the carbon black subjected to the second oxidation treatment.

[0137] (4) The carbon black subjected to the second oxidation treatment is calcined in a nitrogen atmosphere at 400° C. for 6 h to obtain pretreated carbon black.

[0138] The prepared platinum-on-carbon catalyst contained 69% platinum by mass. Measurements showed that the contact angle between the platinum nanoparticles and the carbon support ranged from 30° to 50°, and the average particle size of the platinum nanoparticles was in the range of 3-4 nm. The electrochemical performance of the prepared platinum-on-carbon catalyst was measured, and the experimental results are listed in Table 1.

[0139] Example 7

[0140] (1) 0.3 g of Ketjen EC600J conductive carbon black was added to 600 mL of a mixed solution of deionized water and glycerol (the volume ratio of deionized water to glycerol was 1:1). After mixing, 0.9 g of sodium citrate was added, followed by an aqueous solution of chloroplatinic acid (3.6 mmol of chloroplatinic acid). The resulting mixture was ultrasonically dispersed to form a first dispersion. The ultrasonic power was 200 W, and the ultrasonic dispersion time was 2 h.

[0141] (2) A sodium carbonate aqueous solution was added as a pH adjuster to the first dispersion to adjust the pH of the dispersion to 13, thereby obtaining a second dispersion.

[0142] (3) The third dispersion was heated to 90°C using a heater and stirred, and formic acid and polyvinyl pyrrolidone were added as reducing agents to conduct a reduction reaction. The molar ratio of the reducing agent to chloroplatinic acid was 200:1, and the molar ratio of formic acid to polyvinyl pyrrolidone in the reducing agent was 1:1. After the addition of the reducing agent, the heating conditions of the heater were maintained unchanged and the reaction was continued for 12 hours.

[0143] After the reaction is complete, the reduction reaction mixture is filtered to collect the solid phase, and the solid phase is washed with deionized water until the washing liquid is neutral. The washed solid phase is vacuum dried at 100°C for 12 hours to obtain 1g of the platinum-carbon catalyst according to the present invention. The mass content of platinum in the platinum-carbon catalyst is determined to be 69.5%. The contact angle between the platinum nanoparticles and the carbon support is determined to be in the range of 30° to 50°, and the average particle size of the platinum nanoparticles is in the range of 3-4nm. The electrochemical performance of the prepared platinum-carbon catalyst is measured, and the experimental results are listed in Table 1.

[0144] from Figure 2 It can be seen that in the platinum-carbon catalyst according to the present invention prepared by the method of the present invention, the contact angle between the metal platinum particles and the carbonaceous carrier is less than 50° and between 30°-50°, indicating that in the platinum-carbon catalyst according to the present invention, there is a relatively strong interaction between the metal platinum particles and the carbonaceous carrier.

[0145] Figure 3 and Figure 4 The transmission electron microscope photos of the platinum carbon catalysts prepared in Example 1 and Comparative Example 1 are shown respectively. Figure 3 and Figure 4 By comparison, it can be seen that the platinum-carbon catalyst prepared by the method of the present invention has highly uniform metal platinum cluster particles, and the size of the metal platinum particles is uniform, and the average particle size of the platinum nanoparticles is in the range of 3-4 nm.

[0146] from Figure 5As can be seen from Table 1, Example 1 adopts the method of the present invention to prepare the platinum-carbon catalyst. Compared with Comparative Example 1, the platinum-carbon catalyst prepared in Example 1 shows significantly improved electrochemical catalytic activity.

[0147] Table 1

[0148]

[0149] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, various simple variations of the technical solution of the present invention may be made, including combining the various technical features in any other appropriate manner. These simple variations and combinations should also be regarded as disclosed in the present invention and fall within the scope of protection of the present invention.

Claims

1. A method for preparing a platinum-carbon catalyst, the method comprising the following steps: S1. Dispersing a carbonaceous material, a platinum precursor, a complexing agent, and a dispersion medium using ultrasound to obtain a first dispersion, wherein the complexing agent is one or more of a dicarboxylate and a polycarboxylate, and the dispersion medium is glycerol and water, with a volume ratio of glycerol to water being 0.2-5:1; S2. adjusting the pH value of the first dispersion to 12-14 to obtain a second dispersion; S3. Adding a reducing agent to the second dispersion, allowing the reducing agent to contact the platinum precursor in the second dispersion to perform a reduction reaction, wherein the reducing agent contains polyvinyl pyrrolidone and formic acid, the molar ratio of the reducing agent to the platinum precursor is 150-1000:1, and the molar ratio of polyvinyl pyrrolidone to formic acid is 1:1-5.

2. The method according to claim 1, wherein In the dispersion medium of step S1, the volume ratio of glycerol to water is 0.3-3:

1.

3. The method according to claim 1, wherein In the dispersion medium of step S1, the volume ratio of glycerol to water is 0.5-2:

1.

4. The method according to any one of claims 1 to 3, wherein: In step S1 , the concentration of the platinum precursor relative to the dispersion medium is 1-20 g / L.

5. The method according to any one of claims 1 to 3, wherein: In step S1 , the concentration of the platinum precursor relative to the dispersion medium is 2-10 g / L.

6. The method according to any one of claims 1 to 3, wherein: In step S1 , the concentration of the platinum precursor relative to the dispersion medium is 3-8 g / L.

7. The method according to claim 1, wherein In step S1, the complexing agent is one or more selected from sodium citrate, sodium oxalate, sodium edetate and sodium tartrate.

8. The method according to claim 1 or 7, wherein In step S1, the mass ratio of the platinum precursor to the complexing agent is 1:0.1-7.

9. The method according to claim 1 or 7, wherein: In step S1, the mass ratio of the platinum precursor to the complexing agent is 1:0.2-3.

10. The method according to claim 1 or 7, wherein: In step S1, the mass ratio of the platinum precursor to the complexing agent is 1:0.25-1.

11. The method according to any one of claims 1 to 3 and 7, wherein: In step S1, the platinum precursor is one or more selected from chloroplatinic acid, potassium chloroplatinate and sodium chloroplatinate.

12. The method according to any one of claims 1 to 3 and 7, wherein: In step S1, the carbonaceous material is conductive carbon black.

13. The method according to any one of claims 1 to 3 and 7, wherein: In step S1, the power of the ultrasonic wave is 100-1000W.

14. The method according to any one of claims 1 to 3 and 7, wherein: In step S1, the duration of ultrasonic dispersion is 0.2-5 hours.

15. The method according to any one of claims 1 to 3 and 7, wherein: In step S1, the duration of ultrasonic dispersion is 0.5-3 hours.

16. The method according to claim 1, wherein In the reducing agent of step S3, the molar ratio of polyvinyl pyrrolidone to formic acid is 1:1-3.

17. The method according to claim 1 or 16, wherein In step S3, the molar ratio of the reducing agent to the platinum precursor is 160-800:1, and the platinum precursor is calculated as platinum element.

18. The method according to claim 1 or 16, wherein In step S3, the molar ratio of the reducing agent to the platinum precursor is 180-500:1, and the platinum precursor is calculated as platinum element.

19. The method according to claim 1 or 16, wherein In step S3, the molar ratio of the reducing agent to the platinum precursor is 200-300:1, and the platinum precursor is calculated as platinum element.

20. The method according to claim 1 or 16, wherein In step S3, the reduction reaction is carried out at a temperature of 50-140°C.

21. The method according to claim 1 or 16, wherein In step S3, the reduction reaction is carried out at a temperature of 70-100°C.

22. The method according to claim 1 or 16, wherein In step S3, the duration of the reduction reaction is 4-15 hours.

23. A platinum-carbon catalyst prepared by the method according to any one of claims 1 to 22.

24. Use of the platinum-carbon catalyst according to claim 23 in a fuel cell.

25. A hydrogen fuel cell, wherein the anode and / or cathode of the hydrogen fuel cell comprises the platinum-carbon catalyst according to claim 23.

Images