Preparation method and application of cocklebur-shaped mesoporous carbon loaded platinum alloy catalyst

Abstract

The invention belongs to the technical field of metal nano catalytic materials, and particularly relates to a preparation method and application of a cocklebur-shaped mesoporous carbon loaded platinum alloy catalyst.The preparation method of the platinum-based alloy catalyst.The preparation method of the platinum-based alloy catalyst.The preparation method comprises the steps that firstly, a nano carrier is prepared, platinum nano particles are prepared through reduction of active hydrogen generated through photocatalysis, and the platinum nano particles are loaded on the nano carrier; the preparation method comprises the following steps: preparing a platinum-based alloy catalyst, loading platinum nanoparticles on a nano-carrier, and carrying out evaporation calcination, thereby obtaining the platinum-based alloy catalyst, and the preparation method has the advantages of cheap reactants, simple preparation process, low energy consumption and less pollutant emission; the platinum-based alloy catalyst prepared through the method has the advantages of being good in catalytic performance, good in stability, long in service life and the like, has the potential of large-scale production and application, and is wide in application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of metal nanocatalytic materials, and particularly relates to a method for preparing a Xanthium-like mesoporous carbon-supported platinum alloy catalyst. Background Art

[0002] As a type of fuel cell, proton exchange membrane fuel cell (PEMFC) can efficiently convert the chemical energy in hydrogen into electrical energy. Its only product is water. It has the advantages of being clean, efficient, and pollution-free. However, its slow kinetic process severely limits its commercialization. In proton exchange membrane fuel cells, platinum-based catalysts are widely used as electrode catalysts due to their excellent electrocatalytic performance. They are mainly composed of carriers and platinum-based nanoparticles supported on the surface of the carrier. Therefore, the catalytic performance of platinum-based catalysts is affected by the catalytic activity of the platinum-based particles and the synergistic effect of the carrier.

[0003] At present, the catalytic performance of catalysts is mainly improved through the following methods: the first method is to improve the catalytic performance of platinum-based catalysts by alloying platinum with other metals; the second method is to optimize the morphology of the catalyst, such as using core-shell structure, hollow structure, nanowires and nanosheets to improve the catalytic performance of platinum-based catalysts; the third method is to introduce non-metallic elements as dopants to improve the catalytic performance of platinum-based catalysts by changing the electronic structure and adsorption characteristics of platinum; the fourth method is to improve the utilization and stability of platinum by selecting suitable carrier materials to improve the catalytic performance of platinum-based catalysts; the fifth method is to improve the catalytic performance of platinum-based catalysts by improving the atomic utilization of platinum and constructing a continuous network.

[0004] However, in the actual application of platinum-based catalysts, under the acidic corrosion environment of proton exchange membrane fuel cells, the dealloying of platinum-based catalysts leads to the attenuation of catalytic performance; ionomers occupy the surface of platinum-based particles, leading to catalyst poisoning; catalyst particles migrate on the surface of the carrier, leading to the agglomeration of nanoparticles. The above situations will seriously affect the catalytic performance of the catalyst and ultimately lead to the rapid attenuation of fuel cell performance. In addition, in the current preparation process of platinum-based catalysts, the synthesis method still has problems such as high energy consumption, serious environmental pollution, and long preparation process. The traditional synthesis strategy uses high-priced solvents, resulting in high costs and environmental pollution; the reaction needs to be heated to high temperature, which consumes a lot of energy; the catalyst synthesis process is long, resulting in solvent waste and environmental pollution.

[0005] Based on this, there is an urgent need to develop a platinum-based catalyst with good catalytic performance, good stability, simple synthesis process, low energy consumption, less environmental pollution, and potential for large-scale production and application. Summary of the invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art to a certain extent. To this end, the present invention provides a method for preparing a Xanthium-like mesoporous carbon-supported platinum alloy catalyst and its application. The method for preparing a platinum-based alloy catalyst of the present invention has the advantages of cheap reactants, simple preparation process, low energy consumption, and less pollutant emissions; the platinum-based alloy catalyst prepared by the method of the present invention has the advantages of good catalytic performance, good stability, long service life, etc., has the potential for large-scale production and application, and has broad application prospects.

[0007] In the first aspect of the present invention, the present invention proposes a method for preparing a platinum-based alloy catalyst. According to an embodiment of the present invention, it includes: S1: contacting a nitrogen source and / or a sulfur source, an activator and a nano-carrier, and carbonizing the contact to obtain a carbonized polymer; S2: removing excess nickel from the carbonized polymer to obtain mesoporous carbon; S3: fixing platinum nanoparticle colloids on the mesoporous carbon to obtain a composite; S4: depositing a coating material on the surface of the composite to obtain a coating material-composite; S5: alloying the coating material-composite to obtain a coating material-alloy composite; S6: removing excess coating material from the coating material-alloy composite to obtain a platinum-based alloy catalyst. The preparation method according to an embodiment of the present invention has the advantages of cheap reactants, simple preparation process, low energy consumption, and low pollutant emissions. The platinum-based alloy catalyst prepared by the method of the present invention has the advantages of good catalytic performance, good stability, long service life, etc., has the potential for large-scale production and application, and has broad application prospects.

[0008] According to an embodiment of the present invention, the method for preparing a platinum-based alloy catalyst may also have the following additional technical features:

[0009] According to an embodiment of the present invention, the nanocarrier is prepared by the following method: polyacrylic acid, nickel salt and surfactant are contacted to obtain the nanocarrier; wherein the contact is carried out in a reaction medium with a pH of 2 to 8.

[0010] According to an embodiment of the present invention, the molecular weight of the polyacrylic acid is 8000-12000.

[0011] According to an embodiment of the present invention, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate.

[0012] According to an embodiment of the present invention, the surfactant includes a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or hexadecyltrimethylammonium bromide.

[0013] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1:(2-6):(1-3).

[0014] According to an embodiment of the present invention, the reaction medium is water and / or an alcohol aqueous solution.

[0015] According to an embodiment of the present invention, the reagent for adjusting the pH of the reaction medium is an alkaline solution.

[0016] According to an embodiment of the present invention, the pore size of the nanocarrier is 2-50 nm, and the specific surface area is ≥800 m 2 g -1 .

[0017] According to an embodiment of the present invention, the platinum nanoparticle colloid is prepared by the following method: a platinum source, a surfactant and a photocatalyst are contacted to obtain the platinum nanoparticle colloid; wherein the contact is performed under a light source.

[0018] According to an embodiment of the present invention, the platinum source includes one or more of chloroplatinic acid, potassium chloroplatinate and ammonium chloroplatinate.

[0019] According to an embodiment of the present invention, the surfactant is one or more of sodium glycolate, cetyltrimethylammonium bromide, sodium cetyl sulfonate and cetyltrimethylammonium chloride.

[0020] According to an embodiment of the present invention, the photocatalyst includes one or more of titanium dioxide, cadmium sulfide, zinc oxide and cadmium selenide.

[0021] According to an embodiment of the present invention, the weight ratio of the platinum source, the reducing agent and the photocatalyst is 1:(2-10):(5-20).

[0022] According to an embodiment of the present invention, the contacting is performed in a reaction medium.

[0023] According to an embodiment of the present invention, the reaction medium is an alcohol solvent and / or water.

[0024] According to an embodiment of the present invention, the alcohol solvent includes one or more of methanol, ethanol and isopropanol.

[0025] According to an embodiment of the present invention, the activator is an alkali metal hydroxide.

[0026] According to an embodiment of the present invention, the activator includes one or more of potassium hydroxide, sodium hydroxide and potassium nitrate.

[0027] According to an embodiment of the present invention, the nitrogen source includes one or more of urea, melamine, dicyandiamide and amino acid.

[0028] According to an embodiment of the present invention, the sulfur source includes one or more of thiourea, thioacetamide, cysteine ​​and sulfur powder.

[0029] According to an embodiment of the present invention, the carbonization process includes a first-stage carbonization process and a second-stage carbonization process.

[0030] According to an embodiment of the present invention, in the first stage carbonization treatment, the calcination temperature is 200-400° C., the heating rate is 4-6° C. / min, and the holding time is 2-3 h.

[0031] According to an embodiment of the present invention, in the alloying treatment, the calcination temperature is 800-900° C., the heating rate is 4-6° C. / min, and the holding time is 2-3 h.

[0032] According to an embodiment of the present invention, the weight ratio of the nanocarrier to the nitrogen source and / or sulfur source is 1:(0.5-3).

[0033] According to an embodiment of the present invention, the weight ratio of the mesoporous carbon to the platinum nanoparticles is 1:(0.3-3).

[0034] According to an embodiment of the present invention, the plating material is a base metal material.

[0035] According to an embodiment of the present invention, the plating material includes one or more of iron, nickel, cobalt, copper, zinc and manganese.

[0036] According to an embodiment of the present invention, the weight ratio of the composite body to the coating material-coating material in the composite body is 1:(0.3-10).

[0037] According to an embodiment of the present invention, in the alloying treatment, the calcination temperature is 600-800° C., the heating rate is 4-6° C. / min, and the holding time is 2-3 h.

[0038] According to an embodiment of the present invention, the alloying treatment is performed under a mixed gas of an inert gas and hydrogen, and the proportion of hydrogen in the mixed gas is 5-20%.

[0039] According to an embodiment of the present invention, the mass of platinum accounts for 10-70% of the platinum-based alloy catalyst.

[0040] In the second aspect of the present invention, a platinum-based alloy catalyst is provided. According to an embodiment of the present invention, the platinum-based alloy catalyst is prepared by the method described in the first aspect. The platinum-based alloy catalyst according to the embodiment of the present invention has the advantages of good catalytic performance, good stability, etc., and has broad application prospects.

[0041] In the third aspect of the present invention, a method for preparing a nanocarrier is provided. According to an embodiment of the present invention, the method comprises: contacting polyacrylic acid, a nickel salt and a surfactant to obtain a nanocarrier; wherein the contacting is performed in a reaction medium with a pH of 2 to 8.

[0042] According to an embodiment of the present invention, the above method for preparing a nanocarrier may also have the following additional technical features:

[0043] According to an embodiment of the present invention, the molecular weight of the polyacrylic acid is 8000-12000.

[0044] According to an embodiment of the present invention, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate.

[0045] According to an embodiment of the present invention, the surfactant includes a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or hexadecyltrimethylammonium bromide.

[0046] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1:(2-6):(1-3).

[0047] According to an embodiment of the present invention, the reaction medium is water and / or an alcohol aqueous solution.

[0048] According to an embodiment of the present invention, the reagent for adjusting the pH of the reaction medium is an alkaline solution.

[0049] In the fourth aspect of the present invention, the present invention proposes a nanocarrier. According to an embodiment of the present invention, the nanocarrier is prepared by the preparation method of the nanocarrier described in the first aspect. According to an embodiment of the present invention, by controlling the reaction of polyacrylic acid, nickel salt and surfactant at a specific pH value, with the assistance of surfactant, a polyacrylic acid nickel nanocarrier with a Xanthium-like structure can be prepared, and the nanocarrier prepared by this method has a Xanthium-like structure, which can be used to load catalysts and other substances, has the advantages of large specific surface area, high stability, good loading effect, etc., and has broad application prospects.

[0050] According to an embodiment of the present invention, the above-mentioned nanocarrier may also have the following additional technical features:

[0051] According to an embodiment of the present invention, the pore size of the nanocarrier is 2-50 nm, and the specific surface area is ≥800 m 2 g -1 .

[0052] In a fifth aspect of the present invention, the present invention provides a fuel cell. According to an embodiment of the present invention, the fuel cell comprises the platinum-based alloy catalyst described in the fourth aspect. The fuel cell according to the embodiment of the present invention has the advantages of good catalytic performance, good stability, long service life, low cost, convenient preparation, etc., and has broad application prospects.

[0053] In the sixth aspect of the present invention, the present invention proposes the use of the platinum-based alloy catalyst in a fuel cell according to the fifth aspect. According to an embodiment of the present invention, the platinum-based alloy catalyst is used to improve the comprehensive performance of a fuel cell.

[0054] It will be understood by those skilled in the art that the features and advantages described above for the platinum-based alloy catalyst, nanocarrier and fuel cell are also applicable to this application and will not be described in detail here.

[0055] According to an embodiment of the present invention, the above application may also have the following additional technical features:

[0056] According to an embodiment of the present invention, the fuel cell includes one or more of a proton exchange membrane fuel cell, a direct methanol fuel cell and a high temperature fuel cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0058] Figure 1 This is a diagram of a reactor for preparing platinum nanoparticle colloid in Example 1 of the present invention;

[0059] Figure 2 This is a BET curve result diagram of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I in Example 2 of the present invention;

[0060] Figure 3 This is a SEM result image of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I in Example 2 of the present invention;

[0061] Figure 4 This is a graph showing the XRD test results of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I in Example 2 of the present invention;

[0062] Figure 5 This is a graph showing the LSV curve results of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I in Example 2 of the present invention;

[0063] Figure 6 It is a graph showing the LSV curve results of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I, comparative catalyst II, comparative catalyst III and 50% TKK-Pt / C commercial catalyst in Example 2 of the present invention. DETAILED DESCRIPTION

[0064] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0065] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0066] The endpoints and any values ​​of the ranges disclosed in this article 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 endpoint values ​​of each range, the endpoint values ​​of each range and the 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 as specifically disclosed in this article.

[0067] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0068] As used herein, the terms "optionally", "optional" or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0069] In this article, "Pluronic F-127 surfactant" is a non-ionic polymer surfactant that belongs to the family of polyoxyethylene-polyoxypropylene-polyoxyethylene (PEO-PPO-PEO) triblock copolymers.

[0070] In this article, "Xanthium-like mesoporous carbon-supported platinum-based alloy catalyst" is synonymous with "nitrogen-doped mesoporous carbon-supported platinum-copper alloy catalyst" and "supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst".

[0071] Method for preparing platinum-based alloy catalyst

[0072] The present invention proposes a method for preparing a platinum-based alloy catalyst. According to an embodiment of the present invention, the method comprises: S1: contacting a nitrogen source and / or a sulfur source, an activator and a nano-carrier, and performing a carbonization treatment to obtain a carbonized polymer; S2: removing excess nickel from the carbonized polymer to obtain mesoporous carbon; S3: fixing platinum nanoparticle colloid on the mesoporous carbon to obtain a composite; S4: depositing a coating material on the surface of the composite to obtain a coating material-composite; S5: performing an alloying treatment on the coating material-composite to obtain a coating material-alloy composite; S6: removing excess coating material from the coating material-alloy composite to obtain a platinum-based alloy catalyst.

[0073] The inventors first mixed a nanocarrier with a nitrogen / sulfur source and an activator, and calcined the mixture in a programmed manner to carbonize polyacrylic acid and achieve nitrogen / sulfur doping to obtain a carbonized polymer; then, excess nickel in the carbonized polymer was removed by etching and other operations to construct a mesoporous structure to obtain mesoporous carbon; then, a platinum nanoparticle colloid was prepared by a photocatalytic reactor, and then the platinum nanoparticle colloid was uniformly dispersed on the mesoporous carbon; then, the composite was vacuum evaporated to deposit a base metal coating material on the surface of the composite to obtain a coating material-composite; then, high-temperature calcination was performed under a reducing atmosphere to achieve alloying of platinum and the base metal coating material to obtain a coating material-alloy composite; finally, excess base metal coating material was removed by etching and other operations, and its surface was dealloyed to generate a platinum-rich surface to obtain a platinum-based alloy catalyst. The preparation method according to the embodiment of the present invention has the advantages of cheap reactants, simple preparation process, low energy consumption, and less pollutant emissions, and has the potential for large-scale production and application. The platinum-based alloy catalyst prepared by the method of the present invention has the advantages of good catalytic performance, good stability, and long service life, and has the potential for large-scale production and application, and has broad application prospects.

[0074] According to an embodiment of the present invention, the nanocarrier is prepared by the following method: polyacrylic acid, nickel salt and surfactant are contacted to obtain polyacrylic acid nickel nanocarrier; wherein the contact is carried out in a reaction medium with a pH of 2 to 8. According to the preparation method of the embodiment of the present invention, by controlling the reaction of polyacrylic acid, nickel salt and surfactant at a specific pH value, with the assistance of surfactant, a white-green precipitate is generated, and a polyacrylic acid nickel nanocarrier with a Xanthium-like structure can be prepared. The method for preparing the nanocarrier of the present invention has the advantage of a simple preparation method; the nanocarrier prepared by the method of the present invention is a Xanthium-like structure, which can be used to load substances such as catalysts, has the advantages of large specific surface area, high stability, good loading effect, etc., and has broad application prospects.

[0075] According to an embodiment of the present invention, the molecular weight of the polyacrylic acid is 8000 to 12000. Thus, the physical and chemical properties of the prepared nanocarrier are controlled, thereby optimizing its performance as a catalyst carrier.

[0076] According to an embodiment of the present invention, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate. Thus, it is applicable to a variety of nickel salts, so that the most suitable nickel source can be selected according to specific catalytic requirements and cost-effectiveness, and the performance of the nanocarrier can be optimized.

[0077] According to an embodiment of the present invention, the surfactant includes a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or hexadecyltrimethylammonium bromide. Thus, by adding a surfactant, the surface properties of the nanocarrier are adjusted, and the dispersibility and adhesion of the prepared platinum-based alloy catalyst are improved.

[0078] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1: (2-6): (1-3). Thus, by adjusting and optimizing the weight ratio of the polyacrylic acid, the nickel salt and the surfactant, the consistency and repeatability of the prepared nanocarrier are ensured, which is conducive to the later commercial mass production. Exemplarily, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1: 2: 1, 1: 3: 1, 1: 4: 1, 1: 5: 1, 1: 6: 1, 1: 2: 2, 1: 3: 2, 1: 4: 2, 1: 5: 2, 1: 6: 2, 1: 2: 3, 1: 3: 3, 1: 4: 3, 1: 5: 3, 1: 6: 3, preferably 1: (3.2-5.0): (1.5-2.5), more preferably 1: (3.8-4.2): (1.8-2.3).

[0079] According to an embodiment of the present invention, the reaction medium is water and / or an alcohol aqueous solution. Exemplarily, the reaction medium can be one or more of water, methanol aqueous solution, ethanol aqueous solution, ethylene glycol aqueous solution and isopropanol aqueous solution. Thus, the polyacrylic acid, the nickel salt and the surfactant are fully contacted, shortening the preparation time of the nanocarrier.

[0080] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium is 1:(2-6):(1-3):(10-50). Thus, by adjusting and optimizing the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium, the consistency and repeatability of the prepared nanocarrier are ensured, which is conducive to the commercial mass production in the later stage. Exemplarily, the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium is 1:2:1:10, 1:3:1:10, 1:4:1:10, 1:5:1:10, 1:6:1:10, 1:2:2:30, 1:3:2:30, 1:4:2:30, 1:5:2:30, 1:6:2:30, 1:2:3:50, 1:3:3:50, 1:4:3:50, 1:5:3:50, 1:6:3:50, preferably 1:(3.2-5.0):(1.5-2.5):(20-45), more preferably 1:(3.8-4.2):(1.8-2.3):(30-40).

[0081] According to an embodiment of the present invention, the reagent for adjusting the pH of the reaction medium is an alkaline solution. Exemplarily, the alkaline solution includes potassium hydroxide, sodium hydroxide, calcium hydroxide, sodium carbonate, etc. and aqueous solutions thereof; thus, the size, morphology and properties of the prepared nanocarrier are controlled by adjusting the pH value with the alkaline solution.

[0082] According to an embodiment of the present invention, the pore size of the nanocarrier is 2-50 nm, and the specific surface area is ≥800 m 2 g -1 Thus, the prepared nanocarrier has good carrier performance, which plays an important role in maintaining the activity and stability of the loaded material.

[0083] Illustratively, the pore size of the nanocarrier is 2 nm, 3 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, preferably 2 to 10 nm, and more preferably 3 to 5 nm; thereby, the prepared nanocarrier has good carrier performance and its pore size is uniform, further improving its utilization rate and selectivity, so that the carrier exhibits better efficiency and stability in specific applications.

[0084] According to an embodiment of the present invention, the platinum nanoparticle colloid is prepared by the following method: a platinum source, a surfactant and a photocatalyst are contacted to obtain the platinum nanoparticle colloid; wherein the contact is performed under a light source. Thus, by reacting the platinum source, the surfactant and the photocatalyst under a light source, the platinum nanoparticle colloid is prepared efficiently, cleanly and with low energy consumption, providing the basic conditions for the catalyst part for the subsequent preparation of the platinum-based alloy catalyst.

[0085] According to an embodiment of the present invention, the platinum source includes one or more of chloroplatinic acid, potassium chloroplatinate and ammonium chloroplatinate. Thus, it is applicable to a variety of platinum sources, so that the most suitable platinum source can be selected according to specific catalytic requirements and cost-effectiveness, and the performance of the platinum nanoparticle colloid is optimized.

[0086] According to an embodiment of the present invention, the surfactant is one or more of sodium glycolate, hexadecyltrimethylammonium bromide, sodium hexadecylsulfonate and hexadecyltrimethylammonium chloride. Thus, under photocatalytic conditions, active hydrogen is generated to help reduce the platinum in the chloroplatinum source, thereby preparing platinum nanoparticle colloids, providing the basic conditions for the catalyst part for the subsequent preparation of platinum-based alloy catalysts; and by controlling the concentration of the surfactant and the intensity of the light source, the generation rate and particle size of the platinum nanoparticle colloids are jointly controlled. Exemplarily, photocatalytic water decomposition generates active hydrogen as a reducing agent, while reducing the platinum source to platinum nanoparticles, the surfactant sodium glycolate can act as a stabilizer to prevent the aggregation of platinum nanoparticles.

[0087] According to an embodiment of the present invention, the photocatalyst includes one or more of titanium dioxide, cadmium sulfide, zinc oxide and cadmium selenide. Therefore, it is applicable to a variety of photocatalysts, so that the most suitable photocatalyst can be selected according to specific catalytic needs and cost-effectiveness, and the performance of platinum nanoparticle colloid can be optimized. Exemplarily, in an embodiment of the present invention, titanium dioxide is used to generate active hydrogen under light to reduce a platinum source to generate platinum nanoparticles, and further obtain platinum nanoparticle colloid.

[0088] According to an embodiment of the present invention, the intensity of the light source is 100-500 W. Thus, by controlling the light source intensity and surfactant concentration, the generation rate and particle size of the platinum nanoparticle colloid are jointly controlled, and the performance of the subsequently prepared platinum-based alloy catalyst is further optimized.

[0089] According to an embodiment of the present invention, the weight ratio of the platinum source, the surfactant and the photocatalyst is 1:(2-10):(5-20). Thus, by precisely controlling the weight ratio of the platinum source, the reducing agent and the photocatalyst, the preparation process of the platinum nanoparticle colloid is further optimized.

[0090] Exemplarily, the weight ratio of the platinum source, the surfactant and the photocatalyst is 1:2:5, 1:2:10, 1:2:15, 1:2:20, 1:5:5, 1:5:10, 1:5:15, 1:5:20, 1:10:5, 1:10:10, 1:10:15, 1:10:20, preferably 1:(5.0-8.0):(10.0-15.0).

[0091] According to an embodiment of the present invention, the contact is carried out in a reaction medium, thereby allowing the platinum source, the surfactant and the photocatalyst to fully contact in the reaction medium, thereby shortening the preparation time of the platinum nanoparticle colloid.

[0092] According to an embodiment of the present invention, the reaction medium is an alcohol solvent and / or water. Thus, in the reaction medium alcohol solvent and / or water, the platinum source, the surfactant and the photocatalyst are fully contacted, shortening the preparation time of the platinum nanoparticle colloid.

[0093] According to an embodiment of the present invention, the alcohol solvent includes one or more of methanol, ethanol and isopropanol. Thus, in the reaction medium alcohol solvent, the platinum source, the surfactant and the photocatalyst are fully contacted, shortening the preparation time of the platinum nanoparticle colloid. Exemplarily, in an embodiment of the present invention, methanol is used as the reaction medium. While the platinum source, the surfactant and the photocatalyst are fully contacted, because it can also be used as a reducing agent, it contains active hydrogen, which can be activated under the action of photocatalysis and participate in the reduction of platinum in the platinum source, shortening the preparation time of the platinum nanoparticle colloid.

[0094] According to an embodiment of the present invention, the weight ratio of the platinum source, the surfactant, the photocatalyst, the water and the alcohol solvent is 1:(2-10):(5-20):(80-100):(10-30). Thus, by precisely controlling the weight ratio of the platinum source, the reducing agent, the photocatalyst, the water and the alcohol solvent, the preparation process of the platinum nanoparticle colloid is further optimized.

[0095] Exemplarily, the weight ratio of the platinum source, the surfactant, the photocatalyst, the water and the alcohol solvent is 1:2:5:18:90, 1:2:10:18:90, 1:2:15:18:90, 1:2:20:18:90, 1:5:15:18:90, 1:10:15:18:90, preferably 1:(5.0-8.0):(10.0-15.0):(18-25):(88-95).

[0096] According to an embodiment of the present invention, the activator is an alkali metal hydroxide. Thus, the alkali metal hydroxide is used as an activator to promote the carbonization process of the nanocarrier, thereby quickly obtaining a mesoporous carbon carrier with an ideal pore structure.

[0097] According to an embodiment of the present invention, the activator includes one or more of potassium hydroxide, sodium hydroxide and potassium nitrate. Thus, potassium hydroxide or the like is used as an activator to promote the carbonization process of the nanocarrier, thereby quickly obtaining a mesoporous carbon carrier with an ideal pore structure.

[0098] According to an embodiment of the present invention, the nitrogen source includes one or more of urea, melamine, dicyandiamide and amino acid. Thus, a variety of nitrogen sources are provided for selection, and the chemical composition of the nitrogen / sulfur doped mesoporous carbon carrier is precisely controlled according to the actual application conditions, further improving the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst.

[0099] According to an embodiment of the present invention, the sulfur source includes one or more of thiourea, thioacetamide, cysteine ​​and sulfur powder. Thus, a variety of sulfur sources are provided for selection, and the chemical composition of the nitrogen / sulfur doped mesoporous carbon carrier is precisely controlled according to actual application conditions, further improving the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst.

[0100] According to an embodiment of the present invention, the carbonization treatment includes a first-stage carbonization treatment and a second-stage carbonization treatment. Thus, through the first-stage carbonization treatment and the second-stage carbonization treatment, it is fully carbonized to obtain a carbonized polymer, which provides a carrier basis for the platinum-based alloy catalyst prepared subsequently.

[0101] According to an embodiment of the present invention, in the first stage carbonization treatment, the calcination temperature is 200-400°C, the heating rate is 4-6°C / min, and the holding time is 2-3h. Thus, by the first stage carbonization treatment, it is initially carbonized, while avoiding the destruction of the structure caused by the melting of the polymer, providing a basis for the subsequent preparation of the platinum-based alloy catalyst. Exemplarily, in the first stage carbonization treatment, the calcination temperature is 200°C, 250°C, 300°C, 350°C, 400°C, preferably 250-380°C, more preferably 280-350°C; the heating rate is 4°C / min, 5°C / min, 6°C / min, preferably 4.5-5.5°C / min, more preferably 4.8-5.3°C / min; the holding time is 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, preferably 2.2-2.8h, more preferably 2.4-2.7h.

[0102] According to an embodiment of the present invention, in the second stage carbonization treatment, the calcination temperature is 800-900°C, the heating rate is 4-6°C / min, and the holding time is 2-3h. Thus, by the second stage carbonization treatment, it is completely carbonized to obtain a carbonized polymer, which provides a carrier basis for the platinum-based alloy catalyst prepared subsequently. Exemplarily, in the second stage carbonization treatment, the calcination temperature is 800°C, 820°C, 840°C, 860°C, 880°C, 900°C, preferably 820-880°C, more preferably 850-870; the heating rate is 4°C / min, 5°C / min, 6°C / min, preferably 4.5-5.5°C / min, more preferably 4.8-5.3°C / min; the holding time is 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, preferably 2.2-2.8h, more preferably 2.4-2.7h.

[0103] According to an embodiment of the present invention, the weight ratio of the nanocarrier to the nitrogen source and / or sulfur source is 1:(0.5-3). Thus, by controlling the weight ratio of the nitrogen source and the sulfur source, the chemical composition of the nitrogen / sulfur-doped mesoporous carbon carrier is precisely controlled, and the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst are further improved.

[0104] According to an embodiment of the present invention, the weight ratio of the mesoporous carbon to the platinum nanoparticles is 1:(0.3-3). Thus, the dispersibility and loading amount of the platinum nanoparticles on the mesoporous carbon carrier are further optimized, and the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst are further improved.

[0105] Illustratively, the weight ratio of the mesoporous carbon to the platinum source for preparing the platinum nanoparticle colloid is 1:0., 1:1, 1:1.5, 1:2, 1:2.5, 1:3, preferably 1:(0.5-2), more preferably 1:(1-1.2).

[0106] According to an embodiment of the present invention, the coating material is a base metal material. Thus, by using the base metal material as the coating material, a catalyst having a specific metal alloy structure is prepared, further improving the durability and anti-poisoning ability of the platinum-based alloy catalyst.

[0107] According to an embodiment of the present invention, the coating material includes one or more of iron, nickel, cobalt, copper, zinc and manganese. Therefore, according to actual application conditions, a base metal material such as nickel is used as a coating material to prepare a catalyst having a specific metal alloy structure, thereby further improving the catalytic activity, durability and anti-poisoning ability of the platinum-based alloy catalyst.

[0108] According to an embodiment of the present invention, the weight ratio of the composite body to the coating material in the coating material-composite body is 1:(0.3-10). Thus, by controlling the proportion of the coating material in the coating material-composite body, the ratio of the base metal to the platinum in the obtained platinum-based alloy catalyst is precisely controlled, and the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst are further improved.

[0109] According to an embodiment of the present invention, the coating material deposition method includes one or more of vacuum evaporation, chemical vapor deposition, electrochemical deposition and co-precipitation. Thus, the coating material is deposited on the surface of the composite to prepare a coating material-composite. According to an embodiment of the present invention, the coating material deposition method is vacuum evaporation, and the coating material is deposited on the surface of the composite by vacuum evaporation. This method is clean, efficient and environmentally friendly, further reduces energy consumption and pollution, and further improves the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst.

[0110] According to an embodiment of the present invention, in the alloying treatment, the calcination temperature is 600-800°C, the heating rate is 4-6°C / min, and the holding time is 2-3h. Thus, through the alloying treatment, the coating material and the mesoporous carbon carrier are closely combined to obtain a coating material-alloy composite, further improving the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst. Exemplarily, in the alloying treatment, the calcination temperature is 600°C, 50°C, 700°C, 750°C, 800°C, preferably 620-780°C, more preferably 650-770; the heating rate is 4°C / min, 5°C / min, 6°C / min, preferably 4.5-5.5°C / min, more preferably 4.8-5.3°C / min; the holding time is 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, preferably 2.2-2.8h, more preferably 2.4-2.7h.

[0111] According to an embodiment of the present invention, the alloying treatment is performed under a mixed gas of inert gas and hydrogen, wherein the proportion of hydrogen in the mixed gas is 5-20%. Thus, the platinum nanoparticles and the coating material are alloyed under high temperature conditions to generate a platinum-based alloy.

[0112] According to an embodiment of the present invention, the mass of platinum in the platinum-based alloy catalyst accounts for 10-70%. Therefore, by determining the proportion of platinum in the platinum-based alloy catalyst, the composition of the catalyst is accurately controlled, and the electrocatalytic performance and durability of the prepared platinum-based alloy catalyst are further guaranteed.

[0113] Platinum-based alloy catalyst

[0114] The present invention provides a platinum-based alloy catalyst. According to an embodiment of the present invention, the platinum-based alloy catalyst is prepared by the aforementioned method. The platinum-based alloy catalyst according to the embodiment of the present invention has the advantages of good catalytic performance, good stability, etc., and has broad application prospects.

[0115] Method for preparing nanocarrier

[0116] The present invention proposes a method for preparing a nanocarrier. According to an embodiment of the present invention, the method comprises: contacting polyacrylic acid, a nickel salt and a surfactant to obtain a polyacrylic acid nickel nanocarrier; wherein the contact is carried out in a reaction medium with a pH of 2 to 8. According to the preparation method of an embodiment of the present invention, by controlling the reaction of polyacrylic acid, a nickel salt and a surfactant at a specific pH value, with the assistance of a surfactant, a polyacrylic acid nickel nanocarrier with a Xanthium-like structure can be prepared and obtained. The method for preparing a nanocarrier of the present invention has the advantage of a simple preparation method; the nanocarrier prepared by the method of the present invention is a Xanthium-like structure, which can be used to load substances such as catalysts, has the advantages of a large specific surface area, high stability, good loading effect, etc., and has broad application prospects.

[0117] According to an embodiment of the present invention, the molecular weight of the polyacrylic acid is 8000 to 12000. Thus, the physical and chemical properties of the prepared nanocarrier are controlled, thereby optimizing its performance as a catalyst carrier.

[0118] According to an embodiment of the present invention, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate. Thus, it is applicable to a variety of nickel salts, so that the most suitable nickel source can be selected according to specific catalytic requirements and cost-effectiveness, and the performance of the nanocarrier can be optimized.

[0119] According to an embodiment of the present invention, the surfactant includes a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or hexadecyltrimethylammonium bromide. Thus, by adding a surfactant, the surface properties of the nanocarrier are adjusted, and the dispersibility and adhesion of the prepared platinum-based alloy catalyst are improved.

[0120] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1: (2-6): (1-3). Thus, by adjusting and optimizing the weight ratio of the polyacrylic acid, the nickel salt and the surfactant, the consistency and repeatability of the prepared nanocarrier are ensured, which is conducive to the later commercial mass production. Exemplarily, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1: 2: 1, 1: 3: 1, 1: 4: 1, 1: 5: 1, 1: 6: 1, 1: 2: 2, 1: 3: 2, 1: 4: 2, 1: 5: 2, 1: 6: 2, 1: 2: 3, 1: 3: 3, 1: 4: 3, 1: 5: 3, 1: 6: 3, preferably 1: (3.2-5.0): (1.5-2.5), more preferably 1: (3.8-4.2): (1.8-2.3).

[0121] According to an embodiment of the present invention, the reaction medium is water and / or an alcohol aqueous solution. Exemplarily, the reaction medium can be one or more of water, methanol aqueous solution, ethanol aqueous solution, ethylene glycol aqueous solution and isopropanol aqueous solution. Thus, the polyacrylic acid, the nickel salt and the surfactant are fully contacted, shortening the preparation time of the nanocarrier.

[0122] According to an embodiment of the present invention, the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium is 1:(2-6):(1-3):(10-50). Thus, by adjusting and optimizing the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium, the consistency and repeatability of the prepared nanocarrier are ensured, which is conducive to the commercial mass production in the later stage. Exemplarily, the weight ratio of the polyacrylic acid, the nickel salt, the surfactant and the reaction medium is 1:2:1:10, 1:3:1:10, 1:4:1:10, 1:5:1:10, 1:6:1:10, 1:2:2:30, 1:3:2:30, 1:4:2:30, 1:5:2:30, 1:6:2:30, 1:2:3:50, 1:3:3:50, 1:4:3:50, 1:5:3:50, 1:6:3:50, preferably 1:(3.2-5.0):(1.5-2.5):(20-45), more preferably 1:(3.8-4.2):(1.8-2.3):(30-40).

[0123] According to an embodiment of the present invention, the reagent for adjusting the pH of the reaction medium is an alkaline solution. Exemplarily, the alkaline solution includes potassium hydroxide, sodium hydroxide, calcium hydroxide, sodium carbonate, etc. and aqueous solutions thereof; thus, the size, morphology and properties of the prepared nanocarrier are controlled by adjusting the pH value with the alkaline solution.

[0124] Nanocarriers

[0125] The present invention proposes a nanocarrier. According to an embodiment of the present invention, the nanocarrier is prepared by the above-mentioned method for preparing the nanocarrier. According to an embodiment of the present invention, by controlling the reaction of polyacrylic acid, nickel salt and surfactant at a specific pH value, with the assistance of the surfactant, a polyacrylic acid nickel nanocarrier with a Xanthium-like structure can be prepared and obtained, and the nanocarrier prepared by the method has a Xanthium-like structure, can be used to load substances such as catalysts, has the advantages of large specific surface area, high stability, good loading effect, etc., and has broad application prospects.

[0126] According to an embodiment of the present invention, the pore size of the nanocarrier is 2-50 nm, and the specific surface area is ≥800 m 2 g -1 Thus, the prepared nanocarrier has good carrier performance, which plays an important role in maintaining the activity and stability of the loaded material.

[0127] Illustratively, the pore size of the nanocarrier is 2 nm, 3 nm, 5 nm, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, preferably 2 to 10 nm, and more preferably 3 to 5 nm; thereby, the prepared nanocarrier has good carrier performance and its pore size is uniform, further improving its utilization rate and selectivity, so that the carrier exhibits better efficiency and stability in specific applications.

[0128] Fuel Cells

[0129] The present invention provides a fuel cell. According to an embodiment of the present invention, the fuel cell comprises the aforementioned platinum-based alloy catalyst. The fuel cell according to the embodiment of the present invention has the advantages of good catalytic performance, good stability, long service life, low cost, convenient preparation, etc., and has broad application prospects.

[0130] application

[0131] The present invention proposes the application of the above-mentioned platinum-based alloy catalyst in a fuel cell. According to an embodiment of the present invention, the platinum-based alloy catalyst is used to improve the electrocatalytic performance of the battery.

[0132] It will be understood by those skilled in the art that the features and advantages described above for the platinum-based alloy catalyst, nanocarrier and fuel cell are also applicable to this application and will not be described in detail here.

[0133] According to an embodiment of the present invention, the fuel cell includes one or more of a proton exchange membrane fuel cell, a direct methanol fuel cell and a high temperature fuel cell. Therefore, the platinum-based alloy catalyst is suitable for a variety of fuel cells, especially proton exchange membrane fuel cells.

[0134] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0135] Example 1: Preparation of Xanthium-like mesoporous carbon supported platinum-based alloy catalyst I

[0136] Step S1: Preparation of nickel polyacrylate nanospheres

[0137] 18 g of Pluronic F-127 surfactant (purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.), 120 g of water, 10 g of nickel nitrate hexahydrate, and 4 g of polyacrylic acid with a molecular weight of 8000 were accurately weighed to prepare a solution, and after ultrasonication for 40 min, 10 g of nickel nitrate hexahydrate was added and stirred for 10 min. 5 mol / L potassium hydroxide was added dropwise until the pH was 2.0-8.0, and stirring was continued for 10 h. The solution was filtered and dried to obtain polyacrylic acid nickel nanospheres.

[0138] Step S2: Preparation of nitrogen / sulfur doped mesoporous carbon

[0139] Accurately weigh 3g of urea, 3g of potassium hydroxide, and 2g of the polyacrylic acid nickel nanospheres prepared in step S1, mix and grind the three, place them in a 99.99% nitrogen atmosphere, heat them to 300°C at a heating rate of 5°C / min, and keep them warm for 2h to initially carbonize the polymer of the three to avoid structural damage caused by melting of the polymer; then heat them to 800°C at a heating rate of 5°C / min, and keep them warm for 2h to completely carbonize the above polymer; cool to room temperature, and etch the nickel in the above polymer with 3mol / L nitric acid solution, react for 10h, filter, wash with water, and dry to obtain nitrogen / sulfur-doped mesoporous carbon.

[0140] Step S3: Preparation of platinum nanoparticle colloid

[0141] Weigh 3g of chloroplatinic acid hydrate, 50g of methanol, and 20g of sodium glycolate and dissolve them in 300mL of water. Keep the mixture under ultrasonic conditions of 200W of ultrasonic power and 40kHz of ultrasonic frequency for 40min. During the whole process, the temperature should be kept below 25°C to ensure uniform dispersion. Then arrange the titanium mesh covered with a titanium dioxide layer in the solution and irradiate and reduce it with a 500W high-pressure mercury lamp for 10h to obtain glycolic acid-stabilized platinum nanoparticle colloid.

[0142] The reactor for preparing platinum nanoparticle colloids is shown in Figure 1 .

[0143] Step S4: Preparation of Pt / C composite

[0144] 0.8 g of the platinum nanoparticle colloid prepared in step S3 was mixed with 0.8 g of the nitrogen / sulfur-doped mesoporous carbon prepared in step S2 to make the Pt content about 50%, and ultrasonicated for 40 min (ultrasonic power 200 W, ultrasonic frequency 40 kHz) to make it evenly dispersed, and then 3 mol / L nitric acid solution was added dropwise to pH = 2. After filtering, washing with water and drying, a Pt / C complex was obtained.

[0145] Step S5: Vacuum evaporation of Cu

[0146] Weigh 2 g of the Pt / C composite obtained in step S4 and place it in a vacuum evaporation chamber. Select a Cu target (coating material) and perform vacuum evaporation for 2 hours under ultrasonic stirring (ultrasonic power 80 W, ultrasonic frequency 40 kHz) to obtain a Pt / C-Cu composite.

[0147] Step S6: Calcination to form a Pt-Cu alloy composite

[0148] 5 g of the Pt / C-Cu composite obtained in step S5 was weighed and placed in a 10% hydrogen-nitrogen mixed atmosphere (hydrogen volume accounting for 10%, nitrogen volume accounting for 90%), and the temperature was raised to 700° C. at a heating rate of 5° C. / min, and kept warm for 2 h to alloy Cu and Pt, and then cooled to room temperature to obtain a Pt-Cu alloy composite.

[0149] Step S7: Etching process

[0150] Weigh 5 g of the Pt-Cu alloy complex obtained in step S6, place it in an etching solution with a nitric acid concentration of 1 mol / L and a ferric nitrate concentration of 0.5 mol / L, heat it to 60°C, and react for 2 hours to remove excess Cu and dealloy the alloy surface to generate a platinum-rich surface, then filter, wash with water, and dry to obtain a supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I (nitrogen-doped mesoporous carbon-supported platinum-copper alloy catalyst I).

[0151] Step S8: Crushing

[0152] The supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst prepared in step S6 is placed in a grinder and ground for 30 seconds to obtain supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst powder I (nitrogen-doped mesoporous carbon-supported platinum-copper alloy catalyst powder I).

[0153] Comparative Example 1: Preparation of Comparative Catalyst II

[0154] The difference between Example 2 and Example 1 is that the steps of vacuum evaporation of Cu, calcination to form a Pt-Cu alloy composite, and etching treatment are missing. The specific preparation method is as follows:

[0155] Step S1: Preparation of nickel polyacrylate nanospheres

[0156] This step is the same as step S1 of embodiment 1.

[0157] Step S2: Preparation of nitrogen / sulfur doped mesoporous carbon

[0158] This step is the same as step S2 of Example 1.

[0159] Step S3: Preparation of platinum nanoparticle colloid

[0160] This step is the same as step S3 of Example 1.

[0161] Step S4: Preparation of Pt / C composite

[0162] This step is the same as step S4 of Example 1.

[0163] Step S5: Crushing

[0164] This step is the same as step S8 of Example 1, and a comparative catalyst II powder is obtained.

[0165] Comparative Example 2: Preparation of Comparative Catalyst III

[0166] The difference between Example 3 and Example 1 lies in step 2 and step 4, which are as follows:

[0167] Step S1: Preparation of nickel polyacrylate nanospheres

[0168] This step is the same as step S1 of embodiment 1.

[0169] Step S2: Preparation of mesoporous carbon

[0170] The difference between this step and Example 1 is that 3g of urea and 3g of potassium hydroxide are not added. The specific steps are as follows:

[0171] Weigh 2g of S1 nanospheres, place them in a 99.99% nitrogen atmosphere, heat them to 300°C at a heating rate of 5°C / min, and keep them warm for 2h to allow the polymer to be initially carbonized to avoid structural damage caused by polymer melting; heat them to 800°C at a heating rate of 5°C / min and keep them warm for 2h to completely carbonize the above reactants; cool them to room temperature, and etch the nickel therein with a 3mol / L nitric acid solution. React for 10h, filter, wash with water, and dry to obtain mesoporous carbon.

[0172] Step S3: Preparation of platinum nanoparticle colloid

[0173] This step is the same as step S3 of Example 1.

[0174] Step S4: Preparation of Pt / C composite

[0175] The difference between this step and Example 1 is that the nitrogen / sulfur-doped mesoporous carbon is replaced by mesoporous carbon. The specific steps are as follows:

[0176] 0.8 g of the platinum nanoparticle colloid obtained in step S3 was mixed with 0.8 g of the mesoporous carbon obtained in step S2 to make the Pt content about 50%, and maintained under ultrasonic conditions of 200 W of ultrasonic power and 40 kHz of ultrasonic frequency for 40 min. The temperature was kept below 25° C. during the whole process to make it evenly dispersed, and then 3 mol / L nitric acid solution was added dropwise to pH = 2. After filtering, washing with water and drying, a Pt / C complex was obtained.

[0177] Step S5: Vacuum evaporation of Co

[0178] The difference between this step and Example 1 is that the coating material Cu is replaced by the coating material Co. The specific steps are as follows:

[0179] Weigh 2 g of the Pt / C composite prepared in step S4 and place it in a vacuum evaporation chamber. Select a Co target (coating material) and perform vacuum evaporation for 2 hours under ultrasonic stirring (ultrasonic power 80 W, ultrasonic frequency 40 kHz) to obtain a Pt / C-Co composite.

[0180] Step S6: Calcination to form a Pt-Co alloy composite

[0181] This step is the same as step S6 of embodiment 1.

[0182] Step S7: Etching process

[0183] This step is the same as step S7 of Example 1 to obtain comparative catalyst III (mesoporous carbon-supported platinum-cobalt alloy catalyst III)

[0184] Step S8: Crushing

[0185] This step is the same as step S8 of Example 1, and a comparative catalyst III powder (mesoporous carbon-supported platinum-cobalt alloy catalyst III powder) is obtained.

[0186] Example 2: Performance test of Xanthium-like mesoporous carbon supported platinum-based alloy catalyst I

[0187] The supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 and the comparative catalysts II and III prepared in Comparative Example I and Comparative Example II were tested for relevant properties, as follows:

[0188] 1. Specific surface area and pore size detection

[0189] The specific surface area and pore size of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 were measured.

[0190] The BET curve of supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I is shown in Figure 2 .

[0191] The results show that the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 exhibits a porous structure, and the specific surface area of ​​the material is as high as 1292.51 m 2 / g, and the pore sizes are mostly distributed in the range of 3 to 5 nm, which belongs to mesoporous carbon.

[0192] 2. Scanning electron microscope detection

[0193] The supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 was examined by scanning electron microscopy.

[0194] The SEM results of supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I are shown in Figure 3 .

[0195] The results show that the surface of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 is rough, which can provide abundant active sites for the attachment of Pt particles and alleviate the migration and agglomeration of Pt particles.

[0196] 3. X-ray diffraction detection

[0197] The supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 was subjected to X-ray diffraction detection.

[0198] The XRD test results of supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I are shown in Figure 4 .

[0199] The results showed that the XRD image of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 was significantly different from the Pt standard image, and the diffraction peak shifted to a high angle, which was caused by the alloying of Cu and Pt, indicating that the platinum-copper alloy was successfully synthesized.

[0200] 4. Electrochemical stability test

[0201] The electrochemical stability test of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 was carried out.

[0202] The LSV curve results of supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I are shown in Figure 5 .

[0203] The results showed that: comparing the initial LSV curve and the LSV curve after 30,000 cycles, the two were basically consistent, indicating that the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 had excellent stability, and could still retain a mass activity of up to 508 mA / mg after 30,000 cycles, with a mass activity retention rate of up to 90.6%, indicating that the catalyst had excellent stability.

[0204] 5. Electrochemical comparison test

[0205] Electrochemical comparative tests were performed on the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I, comparative catalyst II, comparative catalyst III and commercially available 50% TKK-Pt / C commercial catalyst (purchased from Tanaka Precious Metals Group Co., Ltd.) prepared in Examples 1 to 3.

[0206] The LSV curves of supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I, comparative catalyst II, comparative catalyst III and 50% TKK-Pt / C commercial catalyst are shown in Figure 6 .

[0207] The results show that the initial mass activity of the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 at 0.9V is as high as 561mA / mg, which is much higher than the commercially available 50% TKK-Pt / C commercial catalyst (161mA / mg), the comparative catalyst II prepared in Example 2 (203mA / mg) and the comparative catalyst III prepared in Example 3 (323mA / mg), indicating that the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst I prepared in Example 1 has very excellent catalytic activity and has great application potential.

[0208] The test results 1 to 5 above indicate that the supported Xanthium-like mesoporous carbon-platinum-based alloy catalyst prepared by the method of the present invention has better catalytic activity and catalytic stability than commercially available catalysts.

[0209] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0210] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a platinum-based alloy catalyst, characterized in that: include: S1: contacting a nitrogen source and / or a sulfur source, an activator and a nanocarrier, and performing a carbonization treatment to obtain a carbonized polymer; S2: removing excess nickel from the carbonized polymer to obtain mesoporous carbon; S3: fixing the platinum nanoparticle colloid on the mesoporous carbon to obtain a composite; S4: depositing a coating material onto the surface of the composite to obtain a coating material-composite; S5: alloying the coating material-composite to obtain a coating material-alloy composite; S6: removing excess coating material from the coating material-alloy composite to obtain a platinum-based alloy catalyst.

2. The method according to claim 1, characterized in that The nanocarrier is prepared by the following method: contacting polyacrylic acid, nickel salt and surfactant to obtain the nanocarrier; Wherein, the contact is carried out in a reaction medium with a pH of 2 to 8; Optionally, the molecular weight of the polyacrylic acid is 8000 to 12000; Optionally, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate; Optionally, the surfactant comprises a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or cetyltrimethylammonium bromide; Optionally, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1:(2-6):(1-3); Optionally, the reaction medium is water and / or an alcohol aqueous solution; Optionally, the reagent for adjusting the pH of the reaction medium is an alkaline solution; Optionally, the nanocarrier has a pore size of 2 to 50 nm and a specific surface area of ​​≥800 m 2 g -1 .

3. The method according to claim 1, characterized in that The platinum nanoparticle colloid is prepared by the following method: A platinum source, a surfactant and a photocatalyst are brought into contact to obtain a platinum nanoparticle colloid; wherein the contact is performed under a light source; Optionally, the platinum source includes one or more of chloroplatinic acid, potassium chloroplatinate and ammonium chloroplatinate; Optionally, the surfactant is one or more of sodium glycolate, cetyltrimethylammonium bromide, sodium cetyl sulfonate and cetyltrimethylammonium chloride; Optionally, the photocatalyst comprises one or more of titanium dioxide, cadmium sulfide, zinc oxide and cadmium selenide; Optionally, the weight ratio of the platinum source, the surfactant and the photocatalyst is 1:(2-10):(5-20); Optionally, the contacting is carried out in a reaction medium; Optionally, the reaction medium is an alcohol solvent and / or water; Optionally, the alcohol solvent includes one or more of methanol, ethanol and isopropanol.

4. The method according to claim 1, characterized in that: The activator is an alkali metal hydroxide; Optionally, the activator comprises one or more of potassium hydroxide, sodium hydroxide and potassium nitrate; Optionally, the nitrogen source comprises one or more of urea, melamine, dicyandiamide and amino acids; Optionally, the sulfur source comprises one or more of thiourea, thioacetamide, cysteine ​​and sulfur powder; Optionally, the carbonization treatment includes a first-stage carbonization treatment and a second-stage carbonization treatment; Optionally, in the first stage carbonization treatment, the calcination temperature is 200-400°C, the heating rate is 4-6°C / min, and the holding time is 2-3h; Optionally, in the second stage carbonization treatment, the calcination temperature is 800-900°C, the heating rate is 4-6°C / min, and the holding time is 2-3h; Optionally, the weight ratio of the nanocarrier to the nitrogen source and / or sulfur source is 1:(0.5-3); Optionally, the weight ratio of the mesoporous carbon to the platinum nanoparticles is 1:(0.3-3); Optionally, the coating material is a base metal material; Optionally, the coating material includes one or more of iron, nickel, cobalt, copper, zinc and manganese; Optionally, the weight ratio of the composite body to the coating material-coating material in the composite body is 1:(0.3-10); Optionally, in the alloying treatment, the calcination temperature is 600-800°C, the heating rate is 4-6°C / min, and the holding time is 2-3h; Optionally, the alloying treatment is carried out under a mixed gas of inert gas and hydrogen, and the proportion of hydrogen in the mixed gas is 5-20%; Optionally, the mass of platinum in the platinum-based alloy catalyst accounts for 10-70%.

5. A platinum-based alloy catalyst, characterized in that: The platinum-based alloy catalyst is prepared by the method according to any one of claims 1 to 4.

6. A method for preparing a nanocarrier, characterized in that: include: contacting polyacrylic acid, nickel salt and surfactant to obtain a nanocarrier; Wherein, the contact is carried out in a reaction medium with a pH of 2-8.

7. The method according to claim 6, characterized in that The molecular weight of the polyacrylic acid is 8000 to 12000; Optionally, the nickel salt includes one or more of nickel nitrate, nickel chloride, nickel acetate and nickel sulfate; Optionally, the surfactant comprises a polyoxyethylene-polyoxypropylene-polyoxyethylene triblock copolymer and / or cetyltrimethylammonium bromide; Optionally, the weight ratio of the polyacrylic acid, the nickel salt and the surfactant is 1:(2-6):(1-3); Optionally, the reaction medium is water and / or an alcohol aqueous solution; Optionally, the agent for adjusting the pH of the reaction medium is an alkaline solution.

8. A nanocarrier, characterized in that: The nanocarrier is prepared by the method of claim 6 or 7; Optionally, the nanocarrier has a pore size of 2 to 50 nm and a specific surface area of ​​≥800 m 2 g -1 .

9. A fuel cell, characterized in that: Comprising the platinum-based alloy catalyst as claimed in claim 5.

10. Use of the platinum-based alloy catalyst according to claim 5 in a fuel cell, characterized in that: The platinum-based alloy catalyst is used to improve the comprehensive performance of the fuel cell; Optionally, the fuel cell comprises one or more of a proton exchange membrane fuel cell, a direct methanol fuel cell and a high temperature fuel cell.

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