Carrier composite platinum-nickel alloy catalyst as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of energy materials and electrochemistry, and particularly relates to a carrier composite platinum-nickel alloy catalyst and a preparation method and application thereof. The preparation method comprises the following steps: (1) ball-milling and dispersing a carbon carrier into a solvent to form a uniform suspension; adding nickel salt into the uniform suspension, and shearing and dispersing to form uniform slurry; introducing an inert atmosphere into the uniform slurry, adding a platinum raw material solution, and carrying out ultrasonic shearing dispersion to form uniformly dispersed carbon slurry; (2) carrying out rotary evaporation on the carbon paste, and drying to obtain a metal precursor; (3) mixing, ball-milling and dispersing the metal precursor and the nitrogen source precursor; and (4) putting the obtained mixture into a tubular furnace, introducing inert gas for purging, heating, cooling, and taking out to obtain the carrier composite platinum-nickel alloy catalyst. According to the invention, the composite carrier is introduced in the preparation process of the catalyst, so that the binding force of the catalyst carrier to PtNi nanoparticles and the tolerance of high potential can be improved.

Description

Technical Field

[0001] The invention belongs to the technical field of energy materials and electrochemical technology, and specifically relates to a carrier composite platinum-nickel alloy catalyst and a preparation method and application thereof. Background Art

[0002] A fuel cell is a device that directly converts chemical energy into electrical energy. It has the advantages of high energy conversion efficiency, low or zero emissions, and environmental friendliness. Fuel cells use hydrogen as fuel, which can be obtained by electrolyzing water or from local energy sources. It can significantly reduce dependence on oil and has an important impact on national security issues. In hydrogen-oxygen fuel cells, the oxygen reduction reaction (ORR reaction) occurring on the cathode side involves a multi-electron transfer reaction, which has slow kinetics. Therefore, it is necessary to select a suitable catalyst to increase the reaction rate and reduce the reaction overpotential. The precious metal Pt is a good catalyst for the ORR reaction, but there are two important problems in the application of Pt-based catalysts. First, Pt is expensive and has a high cost, which limits the large-scale commercial application of Pt-based catalysts. Therefore, it is necessary to reduce the amount of Pt. Second, the traditional carbon carrier has a weak binding force with Pt. At high potential, the carbon carrier will corrode, causing the Pt active site to fall off. Therefore, reducing the amount of Pt and increasing the binding force between Pt and the carrier can effectively reduce the catalyst cost and improve the durability of the catalyst. At present, the strategies for improving the durability of Pt-based catalysts mainly focus on the modification of carbon carriers, such as carrier graphitization, nitrogen doping and sulfurization. While these methods improve the durability of the carrier, they will inevitably cause a decrease in the number of active sites at the catalyst / carrier interface, which is not conducive to its application in fuel cell systems. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a carrier composite platinum-nickel alloy catalyst and its preparation method and application. In view of the instability of the catalyst and supporting materials in the existing platinum alloy catalyst under harsh electrochemical environment, a composite carrier is introduced in the catalyst preparation process to improve the binding force of the catalyst carrier to PtNi nanoparticles and the tolerance to high potential.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the embodiment of the present invention is:

[0005] In a first aspect, an embodiment of the present invention provides a method for preparing a carrier composite platinum-nickel alloy catalyst, comprising the following steps:

[0006] (1) Preparation of carbon slurry: The carbon carrier is dispersed in a solvent by ball milling at a speed of 300-1200 rpm for 30-180 min to form a uniform suspension;

[0007] Add nickel salt to the above uniform suspension, and shear and disperse for 5-120 minutes to form a uniform slurry;

[0008] After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a platinum raw material solution is added, and ultrasonic shearing dispersion is performed for 5-180 minutes to form a uniformly dispersed carbon slurry;

[0009] (2) Precursor rotary evaporation: The carbon slurry obtained in step (1) is rotary evaporated and placed in a drying oven at 60-80° C. for 8-24 h to obtain a metal precursor;

[0010] (3) Carrier composite: The metal precursor and the nitrogen source precursor obtained in step (2) are placed in a planetary ball mill for mixed ball milling, and dispersed at a rotation speed of 300-1200 rpm for 30-240 min;

[0011] (4) High-temperature reduction: The mixed material obtained in step (3) is placed in a tubular furnace, and an inert gas is introduced for purging to remove the air in the furnace, and the mixture is heated and taken out after cooling to obtain a carrier composite platinum-nickel alloy catalyst.

[0012] Furthermore, in step (1), the carbon carrier is a combination of one or more of Ketjen black, Cabot conductive black, acetylene black and VX72R.

[0013] Furthermore, in step (1), the nickel salt is a combination of one or more of nickel nitrate, nickel chloride, nickel acetate, nickel sulfate, nickel chloride hexahydrate and nickel acetate tetrahydrate;

[0014] The amount of the nickel salt added satisfies that the mass of nickel in the nickel salt accounts for 1-20% of the mass of the carrier composite platinum-nickel alloy catalyst.

[0015] Furthermore, in step (1), the platinum source in the platinum raw material solution is selected from a combination of one or more of chloroplatinic acid, dinitrosodiammineplatinum and platinous chloride, and the mass of platinum accounts for 30-65% of the mass of the carrier composite platinum-nickel alloy catalyst.

[0016] Furthermore, in step (1), the solvent is selected from a combination of one or more of water, methanol, ethanol and ethylene glycol, and the mass of the solvent is 0.1-100 times the mass of the carbon carrier.

[0017] Furthermore, in step (3), the nitrogen source precursor is one or more of melamine, urea, cyanamide, dicyandiamide and guanidine, and the mass of the nitrogen source precursor accounts for 1%-40% of the total mass of the metal precursor and the nitrogen source precursor.

[0018] Furthermore, the heating procedure in step (4) is: first, at 2-5°C·min -1Heat to 100-200℃ at a heating rate, keep warm for 30-120min, and then heat at 2-5℃·min -1 Heat to 400-800℃ at a heating rate of 100-200min and keep warm for 60-240min.

[0019] In a second aspect, an embodiment of the present invention provides a carrier composite platinum-nickel alloy catalyst, which is prepared using the preparation method described in the first aspect.

[0020] In a third aspect, an embodiment of the present invention provides an application of the carrier composite platinum-nickel alloy catalyst described in the second aspect, wherein the catalyst is applied to a cathode of a fuel cell.

[0021] The technical solution provided by the embodiment of the present invention has the following beneficial effects:

[0022] 1. The preparation method of the present invention simultaneously dopes nitrogen during alloying, generates graphitized carbon nitride (g-C3N4) in situ, avoids uneven doping caused by subsequent addition, and introduces more active sites, making the conductivity stronger. The existing nitrogen doping technology is to first dope the carbon carrier with nitrogen and then load the metal. In this method, the nitrogen content will be lost during the subsequent alloying process, reducing the active sites and thus reducing the catalyst activity.

[0023] 2. The present invention dopes a small amount of g-C3N4 material, which can not only adjust the electronic structure of the carbon carrier, but also the high content of nitrogen is conducive to the stronger adsorption, coordination and anchoring of g-C3N4 with Pt and Ni elements, reducing the agglomeration, dissolution and shedding of Pt and Ni, thereby increasing the number of active sites of the obtained platinum-based catalyst, improving its catalytic activity and increasing the durability of the carrier.

[0024] 3. The preparation method of the present invention does not require pretreatment. The nitrogen source is calcined together with the alloy precursor to avoid excessive chemical reactions and complex synthesis processes. The production cycle is short and can be expanded. It is expected to replace commercial platinum carbon as an oxygen reduction catalyst.

[0025] 4. The nitrogen-containing carbon carrier of the present invention has good electrical conductivity, which is beneficial to the transfer of charges. At the same time, by doping with a high content of nitrogen, the dispersion of Pt is improved and Pt agglomeration is reduced. In the catalytic process, the utilization rate of platinum in the platinum-based catalyst can be improved, and the platinum loading can be reduced, so that the obtained platinum-based catalyst has the advantages of low platinum and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a transmission electron microscope image of the platinum-nickel alloy composite carrier catalyst prepared in Example 1 of the present invention.

[0027] Figure 2 It is a transmission electron microscope image of the nitrogen-doped carbon support prepared in Comparative Example 1 of the present invention.

[0028] Figure 3 It is the XRD diagram of the platinum-nickel alloy catalyst in Example 1, the nitrogen-doped carbon support and the carbon support in Comparative Example 1.

[0029] Figure 4 These are the performance test results of the fuel cell single cells prepared in Examples 1-2 of the present invention and Comparative Example 2. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] Example 1

[0032] A method for preparing a carrier composite platinum-nickel alloy catalyst comprises the following steps:

[0033] (1) Preparation of carbon slurry: 5 g of VX72R carbon carrier was weighed and dispersed in 100 g of deionized water by ball milling, and dispersed at 500 rpm for 120 min to form a uniform suspension;

[0034] Add nickel chloride raw material liquid to the above uniform suspension so that the mass of nickel accounts for 10% of the mass of the platinum-nickel alloy catalyst, and shear and disperse for 10 minutes to form a uniform slurry;

[0035] After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a chloroplatinic acid solution is added so that the mass of platinum accounts for 40% of the mass of the platinum-nickel alloy catalyst, and ultrasonic shearing and dispersion are performed for 60 minutes to form a uniformly dispersed carbon slurry;

[0036] (2) Rotary evaporation of carbon slurry: Rotary evaporate the carbon slurry obtained in step (1), and place it in a drying oven at 60° C. for 20 h to obtain a metal precursor;

[0037] (3) Carrier composite: The metal precursor obtained in step (2) and 1.25 g of nitrogen source precursor urea were placed in a planetary ball mill for mixing and ball milling at a speed of 600 rpm for 40 min;

[0038] (4) High-temperature reduction: The mixed material in step (3) is placed in a tubular furnace, and an inert gas is introduced to purge the mixture to remove the air in the furnace. The mixture is heated at 5°C / min. -1 The heating rate was 2℃·min and the temperature was kept at 150℃ for 30min. -1 The mixture was heated to 400°C at a heating rate of , and kept at that temperature for 60 minutes. After cooling, the mixture was taken out to obtain a supported composite platinum-nickel alloy catalyst.

[0039] Production of fuel cell single cell: accurately weigh 200 mg of the platinum-nickel alloy catalyst prepared above; measure 20 mL of pure water, 15 mL of isopropanol and 1.5 mL of perfluorosulfonic acid resin solution, add them to the catalyst, crush the cells for 30 minutes, form a uniform catalyst ink, and evenly coat the ink on the cut proton exchange membrane, which is recorded as the cathode; weigh 40% of the platinum-carbon catalyst in the same way, and coat it on the other side of the above membrane, which is recorded as the anode, to form a CCM; the gas diffusion layer uses SGL 28BC model GDL. After the battery is installed and the gas pipeline is connected, the single cell test is carried out after the air tightness test is qualified.

[0040] Example 2

[0041] A method for preparing a carrier composite platinum-nickel alloy catalyst comprises the following steps:

[0042] (1) Preparation of carbon slurry: 5 g of Ketjen black was weighed and dispersed in 100 g of deionized water by ball milling, and dispersed at 500 rpm for 120 min to form a uniform suspension;

[0043] Add nickel chloride raw material liquid to the above uniform suspension so that the mass of nickel accounts for 20% of the mass of the platinum-nickel alloy catalyst, and shear and disperse for 20 minutes to form a uniform slurry;

[0044] After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a dinitrodiammine platinum solution is added so that the mass of platinum accounts for 50% of the mass of the platinum-nickel alloy catalyst, and ultrasonic shearing and dispersion are performed for 100 minutes to form a uniformly dispersed carbon slurry;

[0045] (2) Rotary evaporation of carbon slurry: Rotary evaporate the carbon slurry obtained in step (1), and place it in a drying oven at 80° C. for 14 h to obtain a metal precursor;

[0046] (3) Carrier composite: The metal precursor obtained in step (2) and 1.5 g of nitrogen source precursor melamine were placed in a planetary ball mill for mixing and ball milling at a speed of 1000 rpm for 30 min;

[0047] (4) High-temperature reduction: The mixed material in step (3) is placed in a tubular furnace, and an inert gas is introduced to purge the mixture to remove the air in the furnace. The mixture is heated at 5°C / min. -1 The temperature was heated to 180℃ at a rate of 2℃·min -1 The mixture was heated to 600°C at a heating rate of 1000 °C and kept at that temperature for 40 min. After cooling, the catalyst was taken out to obtain a supported composite platinum-nickel alloy catalyst.

[0048] Production of fuel cell single cell: accurately weigh 200 mg of the platinum-nickel alloy catalyst prepared above; measure 20 mL of pure water, 15 mL of isopropanol and 1.5 mL of perfluorosulfonic acid resin solution, add them to the catalyst, crush the cells for 30 minutes, form a uniform catalyst ink, and evenly coat the ink on the cut proton exchange membrane, which is recorded as the cathode; weigh 40% of the platinum-carbon catalyst in the same way, and coat it on the other side of the above membrane, which is recorded as the anode, to form a CCM; the gas diffusion layer uses SGL 28BC model GDL. After the battery is installed and the gas pipeline is connected, the single cell test is carried out after the air tightness test is qualified.

[0049] Example 3

[0050] A method for preparing a carrier composite platinum-nickel alloy catalyst comprises the following steps:

[0051] (1) 5 g of VX72R carbon carrier was weighed and dispersed in 100 g of deionized water by ball milling, and dispersed at 500 rpm for 120 min to form a uniform suspension;

[0052] Add nickel chloride raw material liquid to the above suspension so that the mass of nickel accounts for 10% of the mass of the platinum-nickel alloy catalyst, and shear and disperse for 10 minutes to form a uniform slurry;

[0053] After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a chloroplatinic acid solution is added so that the mass of platinum accounts for 40% of the mass of the platinum-nickel alloy catalyst, and ultrasonic shearing dispersion is performed for 60 minutes to form a uniformly dispersed carbon slurry;

[0054] (2) Rotary evaporation of carbon slurry: Rotary evaporate the carbon slurry obtained in step (1), and place it in a drying oven at 60° C. for 20 h to obtain a metal precursor;

[0055] (3) placing the metal precursor and the nitrogen source precursor urea in step (2) into a planetary ball mill for mixed ball milling, wherein the mass of the nitrogen source precursor accounts for 1% of the total mass of the metal precursor and the nitrogen source precursor, and dispersing at a speed of 600 rpm for 40 min;

[0056] (4) Place the mixed material in step (3) into a tubular furnace, introduce inert gas for purging, remove the air in the furnace, and heat at 5°C / min. -1 The heating rate was 2℃·min and the temperature was kept at 150℃ for 30min. -1 The mixture was heated to 400°C at a heating rate of , and kept at that temperature for 60 minutes. After cooling, the mixture was taken out to obtain a supported composite platinum-nickel alloy catalyst.

[0057] Production of fuel cell single cell: accurately weigh 200 mg of the composite carrier-loaded catalyst prepared above; measure 20 mL of pure water, 15 mL of isopropanol and 1.5 mL of perfluorosulfonic acid resin solution, add them to the catalyst, crush the cells for 30 minutes, form a uniform catalyst ink, and evenly coat the ink on the cut proton exchange membrane, which is recorded as the cathode; weigh 40% of the platinum carbon catalyst in the same way, and coat it on the other side of the above membrane, which is recorded as the anode, to form a CCM; the gas diffusion layer uses SGL 28BC model GDL. After the battery is installed and the gas pipeline is connected, the single cell test is carried out after the air tightness test is qualified.

[0058] Example 4

[0059] A method for preparing a carrier composite platinum-nickel alloy catalyst comprises the following steps:

[0060] (1) Weigh 5 g of VX72R and disperse it in 100 g of deionized water by ball milling. Disperse at 500 rpm for 120 min to form a uniform suspension.

[0061] Add nickel chloride raw material liquid to the above suspension so that the mass of nickel accounts for 10% of the catalyst, and shear and disperse for 10 minutes to form a uniform slurry;

[0062] After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a chloroplatinic acid solution is added so that the mass of platinum accounts for 40% of the mass of the catalyst, and ultrasonic shearing dispersion is performed for 60 minutes to form a uniformly dispersed carbon slurry;

[0063] (2) Rotary evaporation of carbon slurry: Rotary evaporate the carbon slurry obtained in step (1), and place it in a drying oven at 60° C. for 20 h to obtain a metal precursor;

[0064] (3) placing the metal precursor obtained in step (2) and the nitrogen source precursor urea into a planetary ball mill for mixed ball milling, wherein the mass of the nitrogen source precursor accounts for 40% of the total mass of the metal precursor and the nitrogen source precursor, and dispersing at a speed of 600 rpm for 40 min;

[0065] (4) Place the mixed material in step (3) into a tubular furnace, introduce inert gas for purging, remove the air in the furnace, and heat at 5°C / min. -1 The heating rate was 2℃·min and the temperature was kept at 150℃ for 30min. -1 The catalyst was heated to a higher temperature of 400°C at a heating rate of , and kept at that temperature for 60 minutes. After cooling, the catalyst was taken out to obtain a carrier composite platinum-nickel alloy catalyst.

[0066] Production of fuel cell single cell: accurately weigh 200 mg of the platinum-nickel alloy catalyst prepared above; measure 20 mL of pure water, 15 mL of isopropanol and 1.5 mL of perfluorosulfonic acid resin solution, add them to the catalyst, crush the cells for 30 minutes, form a uniform catalyst ink, and evenly coat the ink on the cut proton exchange membrane, which is recorded as the cathode; weigh 40% of the platinum-carbon catalyst in the same way, and coat it on the other side of the above membrane, which is recorded as the anode, to form a CCM; the gas diffusion layer uses SGL 28BC model GDL. After the battery is installed and the gas pipeline is connected, the single cell test is carried out after the air tightness test is qualified.

[0067] Comparative Example 1

[0068] A method for preparing a nitrogen-doped carbon carrier comprises the following steps:

[0069] (1) Preparation of carbon slurry: 5 g of VX72R carbon carrier was weighed and dispersed in 100 g of deionized water by ball milling, and dispersed at 500 rpm for 120 min to form a uniform suspension;

[0070] (2) Carrier composite: The uniform suspension obtained in step (1) and 1.25 g of nitrogen source precursor urea were placed in a planetary ball mill for mixing and ball milling at a speed of 600 rpm for 40 min;

[0071] (3) High-temperature reduction: The mixed material in step (2) is placed in a tubular furnace, and an inert gas is introduced to purge the mixture to remove the air in the furnace. -1 The heating rate was 2℃·min and the temperature was kept at 150℃ for 30min. -1 The mixture was heated to 400°C at a heating rate of , kept warm for 60 min, and taken out after cooling to obtain the composite carrier g-C3N4.

[0072] Comparative Example 2

[0073] A method for preparing a platinum-nickel alloy catalyst comprises the following steps:

[0074] (1) 5 g of VX72R carbon carrier was weighed and dispersed into 100 g of deionized water by ball milling, and dispersed at 500 rpm for 120 min to form a uniform suspension;

[0075] Add nickel chloride raw material liquid to the above suspension so that the mass of nickel accounts for 10% of the mass of the platinum-nickel alloy catalyst, and shear and disperse for 10 minutes to form a uniform slurry;

[0076] After passing an inert atmosphere into the above-mentioned uniform solution to remove oxygen in the slurry, a chloroplatinic acid solution is added so that the mass of platinum accounts for 40% of the catalyst, and ultrasonic shear dispersion is performed for 60 minutes to form a uniformly dispersed carbon slurry;

[0077] (2) Rotary evaporation of carbon slurry: Rotary evaporate the carbon slurry obtained in step (1), and place it in a drying oven at 60° C. for 20 h to obtain a metal precursor;

[0078] (3) ball milling the metal precursor obtained in step (2) at a speed of 600 rpm for 40 min;

[0079] (4) Place the mixed material in step (3) into a tubular furnace, introduce inert gas for purging, remove the air in the furnace, and heat at 5°C / min. -1 The heating rate was 2℃·min and the temperature was kept at 150℃ for 30min. -1 The mixture was heated to 400°C at a heating rate of , kept at that temperature for 60 min, and taken out after cooling to obtain a platinum-nickel alloy catalyst.

[0080] Production of fuel cell single cell: accurately weigh 200 mg of the platinum-nickel alloy catalyst prepared above; measure 20 mL of pure water, 15 mL of isopropanol and 1.5 mL of perfluorosulfonic acid resin solution, add them to the catalyst, crush the cells for 30 minutes, form a uniform catalyst ink, and evenly coat the ink on the cut proton exchange membrane, which is recorded as the cathode; weigh 40% of the platinum-carbon catalyst in the same way, and coat it on the other side of the above membrane, which is recorded as the anode, to form a CCM; the gas diffusion layer uses SGL 28BC model GDL. After the battery is installed and the gas pipeline is connected, the single cell test is carried out after the air tightness test is qualified.

[0081] Table 1 is the battery performance and accelerated decay test data of Examples 1-2 and Comparative Examples 1-3 of the present invention

[0082]

[0083] Note: In Table 1, MA refers to mass specific activity and ECA refers to electrochemically active area.

[0084] It can be seen from Examples 1-4 and Comparative Example 2 in Table 1 that the samples corresponding to the composite carrier without g-C3N4 have lower mass specific activity and electrochemical specific surface area than the samples containing the composite carrier, but the MA attenuation rate and ECA attenuation rate are greater than those of the samples containing the composite carrier, which indicates that the composite carrier can improve the durability and catalytic activity of the catalyst.

[0085] Depend on Figure 1 It can be seen that the platinum-nickel alloy catalyst is well dispersed on the composite carrier, which is beneficial to the improvement of catalytic activity. Figure 2 It can be seen that the composite carrier prepared in Comparative Example 1 has a good lamellar structure and a large specific surface area, and the above structure is conducive to enhancing the dispersion of metal nanoparticles and the binding force between the metal nanoparticles and the composite carrier.

[0086] Figure 3The XRD patterns of the platinum-nickel alloy catalyst prepared in Example 1 and the composite carrier prepared in Comparative Example 1 are shown in FIG. Figure 3 It can be seen that the main peaks of Comparative Example 1 are near 13.2° and 27.3°, and their corresponding crystal planes are the (100) crystal plane and the (002) crystal plane of g-C3N4, respectively, which indicates that Comparative Example 1 prepared the composite carrier C / g-C3N4; the peak intensities of (100) and (002) corresponding to g-C3N4 in Example 1 are reduced, and there are diffraction peaks at 2θ of about 41.5°, 48.4°, and 70.3°, which are (111) crystal plane, (200) crystal plane, and (220) crystal plane, respectively, indicating that Example 1 successfully prepared the carrier composite platinum-nickel alloy catalyst.

[0087] Figure 4 It is a performance comparison chart of fuel cell single cells prepared by the catalysts in Examples 1-2 and Comparative Example 2. It can be seen that the cell performance prepared by the catalyst of the in-situ doped nitrogen source precursor in Examples 1-2 is better than that of the undoped one, proving that in the present invention, the nitrogen-doped catalyst significantly improves the cell performance.

[0088] The platinum-based catalyst provided in an embodiment of the present invention includes a nitrogen-containing carbon composite carrier and Pt and Ni atoms loaded on a nitrogen-containing carbon carrier, and belongs to a loaded catalyst. The platinum-based catalyst is loaded with Pt and Ni atoms on a nitrogen-containing carbon carrier. On the one hand, the nitrogen-containing carbon carrier itself has good electrical conductivity, which is conducive to the transfer of charge. At the same time, by doping with a high content of nitrogen, not only can the electronic structure of the carbon carrier be adjusted, but also a high content of nitrogen is also conducive to the adsorption, coordination and anchoring of platinum atoms, thereby increasing the number of active sites of the obtained platinum-based catalyst and improving its catalytic activity. On the other hand, platinum atoms are evenly distributed in a single-atom state on the nitrogen-containing carbon carrier, have high dispersibility, and will not agglomerate. The utilization rate of platinum in the platinum-based catalyst can be improved during the catalytic process, and the loading of platinum is reduced, so that the obtained platinum-based catalyst has the advantages of low platinum and high efficiency.

[0089] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to examples, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a carrier composite platinum-nickel alloy catalyst, characterized in that: The following steps are involved: (1) Preparation of carbon slurry: The carbon carrier is dispersed in a solvent by ball milling at a speed of 300-1200 rpm for 30-180 min to form a uniform suspension; Add nickel salt to the above uniform suspension, and shear and disperse for 5-120 min to form a uniform slurry; After passing an inert atmosphere into the uniform slurry to remove oxygen in the slurry, a platinum raw material solution is added, and ultrasonic shearing dispersion is performed for 5-180 min to form a uniformly dispersed carbon slurry; (2) Precursor rotary evaporation: The carbon slurry obtained in step (1) is rotary evaporated and placed in a drying oven at 60-80 °C for 8-24 h to obtain a metal precursor; (3) Carrier composite: The metal precursor and the nitrogen source precursor obtained in step (2) are placed in a planetary ball mill for mixing and ball milling, and dispersed at a speed of 300-1200 rpm for 30-240 min; (4) High-temperature reduction: The mixture obtained in step (3) is placed in a tubular furnace, and an inert gas is introduced for purging to remove the air in the furnace, and the mixture is heated and taken out after cooling to obtain a carrier composite platinum-nickel alloy catalyst.

2. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: In step (1), the carbon carrier is a combination of one or more of Ketjen black, Cabot conductive carbon black, acetylene black and VX72R.

3. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: In step (1), the nickel salt is a combination of one or more of nickel nitrate, nickel chloride, nickel acetate, nickel sulfate, nickel chloride hexahydrate and nickel acetate tetrahydrate; The amount of the nickel salt added satisfies that the mass of nickel in the nickel salt accounts for 1-20% of the mass of the carrier composite platinum-nickel alloy catalyst.

4. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: In step (1), the platinum source in the platinum raw material solution is selected from a combination of one or more of chloroplatinic acid, dinitrosodiammineplatinum and platinous chloride, and the mass of platinum accounts for 30-65% of the mass of the carrier composite platinum-nickel alloy catalyst.

5. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: In step (1), the solvent is selected from a combination of one or more of water, methanol, ethanol and ethylene glycol, and the mass of the solvent is 0.1-100 times the mass of the carbon carrier.

6. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: In step (3), the nitrogen source precursor is one or more of melamine, urea, cyanamide, dicyandiamide and guanidine, and the mass of the nitrogen source precursor accounts for 1%-40% of the total mass of the metal precursor and the nitrogen source precursor.

7. The method for preparing a carrier composite platinum-nickel alloy catalyst according to claim 1, characterized in that: The heating procedure in step (4) is: first, at 2-5 °C·min -1 The temperature was heated to 100-200 °C at a rate of 2-5 °C·min -1 Heat to 400-800 °C at a heating rate of 100-200 min and keep warm for 60-240 min.

8. A carrier composite platinum-nickel alloy catalyst, characterized in that: The preparation method is described in any one of claims 1 to 7.

9. The use of the carrier composite platinum-nickel alloy catalyst according to claim 8, characterized in that: The catalyst is applied to the cathode of a fuel cell.

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