Stabilized preparation method of high-entropy single-atom catalyst, catalyst and application

Abstract

The application provides a kind of high-entropy single-atom catalyst stabilization preparation method, comprising the following steps: using wet ball milling to mix metal salt and loading substrate, prepare mixed slurry;The mixed slurry is freeze-dried to obtain dry powder;Dry powder is treated by rapid joule heating method to prepare high-entropy single-atom catalyst. Wherein, metal salt includes any one of the following three: nitrate, sulfate or acetate;Loading substrate includes graphene, carbon nanotube, carbon black, glucose, melamine or urea, and cerium oxide, silicon oxide or aluminum oxide. The preparation method of the application is simple, efficient and low in production cost: only ball mill and flash equipment are needed in the preparation process, without a large amount of solvent and chemical reagent, which is friendly to the environment. Using wet ball milling combined with freeze-drying can prevent agglomeration and maintain uniformity, and the molecular morphological structure of the prepared high-entropy single-atom catalyst is uniform, which helps to expose more active sites and improve the catalytic performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of catalysts for preparing new energy batteries, in particular to a method for stabilizing preparation of a high-entropy single-atom catalyst, the catalyst and applications. BACKGROUND

[0002] High-entropy single atoms refer to introducing the concept of high entropy into single-atom catalysts, through multiple (usually five or more) different metal elements, in the form of near equimolar ratio, distributed at the nanometer or atomic level. These single atoms are uniformly dispersed on support materials (such as carbon-based materials, oxides, etc.), providing unique electronic structures and catalytic properties through high-entropy effects. In the process of preparing high-entropy single-atom catalysts, existing technical solutions mainly use wet chemical methods, chemical vapor deposition (CVD), atomic layer deposition (ALD), etc.

[0003] However, the above traditional methods have the following problems:

[0004] Long time: Traditional heat treatment methods usually take several hours or even longer to complete. This not only reduces production efficiency, but also increases energy consumption, leading to rising production costs.

[0005] Complex equipment: Traditional methods usually require complex multi-step processing procedures and expensive equipment, increasing the complexity and cost of the preparation process. For example, CVD and ALD methods require precise control of gas flow and reaction environment, which is difficult to operate.

[0006] Metal agglomeration: Long-time high-temperature treatment easily leads to metal atom agglomeration on the surface of the support material, forming nanoparticles. This not only reduces the active sites of single-atom catalysts, but also reduces the performance and stability of the catalyst.

[0007] Limited material selection: Existing methods have limited selection of support materials, making it difficult to meet the needs of different catalytic reactions. In particular, when dealing with carbon-based materials, the compatibility and effectiveness of traditional methods are poor.

[0008] High cost: Long-time processing and complex process flow increase production costs.

[0009] Therefore, there is an urgent need for a fast, low-cost method for preparing high-entropy single-atom catalysts. SUMMARY

[0010] In view of the deficiencies in the prior art, the present application proposes a method for preparing a high-entropy single-atom catalyst,

[0011] to overcome the deficiencies in the prior art.

[0012] The technical solution adopted by the present application is as follows:

[0013] In a first aspect, a method for stabilizing preparation of a high-entropy single-atom catalyst is provided, comprising the following steps: mixing a metal salt and a support substrate using a wet ball milling to prepare a mixed slurry;

[0014] Freezing and drying the mixed slurry to obtain a dry powder;

[0015] Treating the dry powder using a rapid Joule heating method to prepare the high-entropy single-atom catalyst.

[0016] Further, the metal salt comprises any one of the following three:

[0017] Nitrate: ferric nitrate Fe(NO3)3, nickel nitrate Ni(NO3)2, cobalt nitrate Co(NO3)2, copper nitrate Cu(NO3)2, manganese nitrate Mn(NO3)2, palladium nitrate Pd(NO3)2, platinum nitrate Pt(NO3)2;

[0018] Sulfate: ferrous sulfate FeSO4, nickel sulfate NiSO4, cobalt sulfate CoSO4, copper sulfate CuSO4, manganese sulfate MnSO4, platinum sulfate PtSO4, palladium sulfate PdSO4;

[0019] Acetate: ferric acetate Fe(C2H3O2)2, nickel acetate Ni(C2H3O2)2, cobalt acetate Co(C2H3O2)2, copper acetate Cu(C2H3O2)2, manganese acetate Mn(C2H3O2)2, palladium acetate Pd(C2H3O2)2, platinum acetate Pt(C2H3O2)2.

[0020] Further, the support substrate comprises a carbon substrate, and the carbon substrate comprises graphene, carbon nanotubes, carbon black, glucose, melamine, or urea.

[0021] Further, the support substrate comprises a metal oxide substrate, and the metal oxide substrate comprises cerium oxide, silicon oxide, or aluminum oxide.

[0022] Further, the wet ball milling comprises: mixing the support substrate and the metal salt uniformly, adding anhydrous ethanol and ammonia water to form a uniform mixed solution; adding the mixed solution into a ball mill tank, setting the rotation speed of the ball mill to 300-500 rpm, and ball milling at room temperature for 6-12 h; further low-temperature ball milling for 3-4 h under an inert atmosphere.

[0023] Further, the freeze-drying comprises: freezing the mixed slurry, the freezing temperature being-4℃, and the freezing time being 4 hours, and the mixed slurry being completely frozen; starting a freeze-drying machine, setting the vacuum degree to 10 Pa, the sublimation temperature to-20℃, and the sublimation time to 2 hours.

[0024] Further, the rapid Joule heat method comprises: opening a flash heat device vacuum box, placing dry powder on a heating material, after closing the flash heat device vacuum box, vacuumizing and then introducing inert gas, and performing rapid Joule heat treatment on the dry powder according to a predetermined voltage, current, time and number of times.

[0025] Further, the electrode voltage is pre-set to 15-40V, the electrode current is pre-set to 15-80A, the time is pre-set to 0.5-2s, one heating period is 1.5-4s, and the number of heating times is pre-set to 5-10 times.

[0026] In a second aspect, a high-entropy single-atom catalyst is provided, which is prepared according to the preparation method provided in the first aspect.

[0027] In a second aspect, the application provides an application of the high-entropy single-atom catalyst in water electrolysis, fuel cells and metal-air batteries.

[0028] From the above technical solution, the beneficial technical effects of the application are as follows:

[0029] 1. The preparation method is simple, efficient and low in production cost: only a ball mill and a flash heat device are needed in the preparation process, without a large amount of solvent and chemical reagent, and the method is environmentally friendly.

[0030] 2. Wet ball milling combined with freeze-drying is used to prevent agglomeration and maintain uniformity, the high-entropy single-atom catalyst prepared has uniform molecular morphological structure, which helps to expose more active sites and improve the catalytic performance.

[0031] 3. The catalyst prepared has good stability and can be applied to various carbon-based materials and other high-temperature-resistant materials, thereby widening the application range of the high-entropy single-atom catalyst. DETAILED DESCRIPTION

[0032] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art, the drawings needed in the specific embodiments or prior art description will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn according to the actual proportions.

[0033] Figure 1 The preparation method flowchart of the embodiments of the application;

[0034] Figure 2 The temperature-time curve of the rapid Joule heat treatment process in Test 1 of the embodiments of the application;

[0035] Figure 3 The physical picture of the high-entropy single-atom catalyst prepared in Test 1 of the embodiments of the application;

[0036] Figure 4The high-entropy single-atom catalyst prepared for Test 1 of the embodiments of the present application is used for the electrochemical test data graph of the oxygen evolution reaction. DETAILED DESCRIPTION

[0037] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0038] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present application should be understood as the usual meaning understood by the skilled person in the field to which the present application belongs.

[0039] EMBODIMENT

[0040] In order to facilitate the creativity of the technical solutions of the present application by the skilled person, first of all, the concepts of single-atom metal, high-entropy single-atom metal and high-entropy alloy are briefly described:

[0041] Single-atom metal: usually refers to the existence of a metal element in the form of a single atom, and only involves one kind of metal element.

[0042] High-entropy single-atom metal: high-entropy single-atom is composed of multiple different metal atoms, each metal exists in the form of an isolated single atom. In terms of structure, single metal atoms are uniformly dispersed on a base material (usually a carbon base), and each metal atom is distributed independently without forming clusters or alloy phases.

[0043] High-entropy alloy: composed of at least five elements in equimolar or approximately equimolar ratio, which are uniformly distributed in the crystal lattice. In terms of structure, multiple metal elements are randomly distributed in the crystal lattice to form a solid solution structure or an intermetallic compound, which has higher configurational entropy compared to traditional alloys.

[0044] The inventors of the present application have found that in the field of catalysts, high-entropy alloys exhibit good stability and activity in some catalytic reactions, but are not as precise as high-entropy single-atom materials. For high-entropy single-atom catalysts, because multiple metal elements are uniformly dispersed and synergistically involved, the preparation process is more complex, and the problem of uniform dispersion of each metal element under rapid high-temperature treatment and the stability of different metal elements on the carbon base need to be solved.

[0045] The present embodiment provides a method for stabilizing the preparation of high-entropy single-atom electrocatalysts, which mainly requires the use of metal precursors and a support substrate.

[0046] In a specific embodiment, the metal precursor can be selected from any one of the following three metal salts:

[0047] Nitrates: ferric nitrate Fe(NO3)3, nickel nitrate Ni(NO3)2, cobalt nitrate Co(NO3)2, copper nitrate Cu(NO3)2, manganese nitrate Mn(NO3)2, palladium nitrate Pd(NO3)2, platinum nitrate Pt(NO3)2;

[0048] Sulfates: ferrous sulfate FeSO4, nickel sulfate NiSO4, cobalt sulfate CoSO4, copper sulfate CuSO4, manganese sulfate MnSO4, platinum sulfate PtSO4, palladium sulfate PdSO4;

[0049] Acetates: ferric acetate Fe(C2H3O2)2, nickel acetate Ni(C2H3O2)2, cobalt acetate Co(C2H3O2)2, copper acetate Cu(C2H3O2)2, manganese acetate Mn(C2H3O2)2, palladium acetate Pd(C2H3O2)2, platinum acetate Pt(C2H3O2)2.

[0050] The loading substrate includes: a carbon substrate and a metal oxide substrate. In a specific embodiment, the carbon substrate can be selected from: graphene, carbon nanotubes, carbon black, glucose, melamine, urea, etc. The metal oxide can be selected from: cerium oxide (CeO2), silicon oxide (SiO), aluminum oxide (Al2O3), etc.

[0051] When the loading substrate selected is a carbon substrate, some of the carbon substrates need to be pretreated, and the pretreatment method is as follows:

[0052] Glucose, sucrose: remove impurities and moisture by rapid Joule heat treatment to obtain high-purity carbon.

[0053] Using the above metal precursors and loading substrates, the preparation of high-entropy single-atom electrocatalysts is carried out according to the following steps:

[0054] Step 1, using wet ball milling to mix the metal salt and the loading substrate to prepare a mixed slurry

[0055] When preparing the precursor in the form of a mixed slurry, the preferred method for mixing the metal salt and the loading substrate is ball milling. The specific steps are as follows: mix the weighed loading substrate and metal salt precursor uniformly, add anhydrous ethanol and ammonia water according to the weight of the substrate and the precursor, and form a uniform mixed solution; add the mixed solution to the ball mill tank, add an appropriate amount of grinding medium (single silicon dioxide ball, zirconium oxide ball or composite medium); set the ball mill speed to 300-500 rpm, and ball mill at room temperature for 6-12 h to ensure that the mixture is mixed uniformly. Further low-temperature ball milling for 3-4 h under an inert atmosphere (preferably argon) to improve the uniformity and fineness of the particles.

[0056] In this step, the high-energy ball milling and multi-step ball milling process described above can obtain a more uniform mixture of carbon source and metal precursor, which helps to uniformly generate high-entropy single-atom catalysts during the subsequent rapid joule heating process. At the same time, it can reduce the energy required for rapid joule heating and improve the preparation efficiency and reduce the cost. The surface activation treatment with ammonia as a surface activator can improve the reactivity of the metal precursor and promote the uniform dispersion of metal atoms during the subsequent rapid joule heating process.

[0057] Low-temperature ball milling and composite ball milling medium treatment under inert gas protection can effectively control the particle size and morphology of the mixture, which helps to generate high-entropy single-atom catalysts with specific structures during the subsequent rapid joule heating process.

[0058] Step 2, freeze-drying the mixed slurry to obtain dry powder

[0059] First, the mixed slurry is frozen, and in a specific embodiment, the mixed slurry after wet ball milling is poured into the tray of the freeze dryer to ensure uniform distribution of the mixed slurry. The tray is placed in the freeze dryer, and the freezing temperature is set to -4°C, and the freezing time is 4 hours to ensure that the mixed slurry is completely frozen.

[0060] Then the frozen mixed slurry is dried, and the freeze dryer is started, and in a specific embodiment, the vacuum degree is set to 10 Pa, the sublimation temperature is set to -20°C, and the sublimation time is set to 2 hours. After freeze-drying is completed, the dried frozen mixed slurry is taken out of the dryer to obtain loose dry powder.

[0061] In this step, the freeze-drying process is used, and the water is directly sublimated from a solid to a gas, avoiding the problem of particle agglomeration caused by high-temperature drying, making the obtained powder more uniform and loose. The powder after freeze-drying has a large specific surface area, which helps to uniformly disperse and react metal atoms during the subsequent rapid joule heating process, improving the activity of the catalyst. At the same time, freeze-drying in a low-temperature and vacuum environment can effectively reduce the introduction of impurities, maintain the purity of the material, and improve the performance of the catalyst. The loose powder structure obtained is beneficial to uniform heating during the subsequent rapid joule heating process, improving the heat conduction efficiency and ensuring uniform reaction and generation of the material. At the same time, the powder structure after freeze-drying is more stable, which is beneficial to maintaining the structural integrity during the subsequent rapid joule heating process, avoiding structural collapse, and improving the long-term stability of the catalyst.

[0062] Step 3, using rapid joule heating method to prepare high-entropy single-atom catalysts for dry powder

[0063] The rapid joule heating method has the following characteristics:

[0064] Uniform heating: The sample is uniformly heated by electric current, avoiding the temperature gradient problem in traditional heating methods, ensuring the uniformity of the material. Strong controllability: The strong current and heating time can be accurately controlled, realizing the precise regulation of the composition and structure of the material, meeting the different application requirements. Wide applicability: This method is suitable for various carbon substrates and metal precursors, and can prepare high-entropy single-atom catalysts with various compositions, with wide applicability.

[0065] The specific operation of the rapid Joule heating method is as follows: open the flash heating device vacuum box, place the dry powder on the heating material, the heating material is not limited to carbon cloth, carbon paper, carbon felt, carbon plate, nickel foil, etc., and the contact heating electrode is preferred in the embodiment. After closing the flash heating device vacuum box, vacuumize, then introduce inert gas (preferably argon), repeat the operation 5 times to ensure that the air in the cavity is completely discharged. Then the dry powder is subjected to rapid Joule heating treatment according to the predetermined voltage, current, time and number of times. The electrode voltage is preset to 15-40V; the electrode current is preset to 15-80A; the time is preset to 0.5-2s; one heating cycle is 1.5-4s; and the number of heating times is preset to 5-10 times.

[0066] The following specific tests are used to illustrate the technical solutions of the present application:

[0067] Test 1

[0068] Urea is used as a carbon source loading substrate, and the metal precursor is iron nitrate, nickel nitrate, copper nitrate, zinc nitrate, and platinum nitrate.

[0069] First, weigh the urea (5 g) and the metal precursors iron nitrate (4.04 g), nickel nitrate (2.91 g), copper nitrate (2.41 g), zinc nitrate (2.97 g), and platinum nitrate (4.41 g), and mix with 10 mL of anhydrous ethanol and 0.5 mL of ammonia water to form a uniform mixed solution; add the mixed solution to the ball mill pot, and add grinding media according to the ball-to-material ratio of 25:1. Set the ball mill speed to 300 rpm, and the room temperature ball milling time to 12h, and further low temperature ball milling for 3h in an inert atmosphere (argon). After ball milling, take out the mixed solution and pour it into the tray of the freeze dryer, ensuring uniform distribution of the slurry. Place the tray in the freeze dryer, set the freezing temperature to -4℃, and the freezing time to 4 hours to ensure complete freezing of the slurry. Start the freeze dryer, set the vacuum degree to 10Pa, the sublimation temperature to -20℃, and the sublimation time to 2 hours. After freeze drying, take out the dry sample from the dryer to obtain loose dry powder.

[0070] The ball-milled powder was evenly laid between the conductive electrodes of the flash heating device, ensuring good contact between the electrodes. The vacuum tank was closed, vacuumed, and then filled with argon, repeating the operation 5 times to ensure that the air in the cavity was completely discharged. The heating parameters were set as follows: applied voltage 25 V, applied current 35 A, processing time 500 ms, and heating cycle 1500 ms. The above repeated heating and cooling was performed 10 times to ensure the uniformity and sufficient reaction of the sample. Figure 2 The temperature-time curve of the rapid Joule heating process of Test 1.

[0071] After the rapid Joule heating process, the sample was taken out of the vacuum tank, ground and sieved appropriately to obtain a uniform high-entropy single-atom catalyst, as shown in Figure 3 .

[0072] Test 2

[0073] Test 2 was basically the same as Test 1, except that the carbon source loading substrate was changed to melamine; the ball mill speed was set to 400 rpm, the room temperature ball milling time was 6 h, and the low temperature ball milling time was 3 h; the applied voltage for rapid Joule heating was 15 V, the applied current was 15 A, the processing time was 1000 ms, and the heating cycle was 2000 ms.

[0074] Test 3

[0075] Test 2 was basically the same as Test 1, except that the carbon source loading substrate was changed to cerium dioxide (CeO2); the ball mill speed was set to 500 rpm, the room temperature ball milling time was 8 h, and the low temperature ball milling time was 4 h; the applied voltage for rapid Joule heating was 40 V, the applied current was 80 A, the processing time was 1500 ms, and the heating cycle was 3000 ms.

[0076] Test 4

[0077] Test 2 was basically the same as Test 1, except that the ball mill speed was set to 500 rpm, the room temperature ball milling time was 10 h, and the low temperature ball milling time was 4 h; the applied voltage for rapid Joule heating was 30 V, the applied current was 65 A, the processing time was 2000 ms, and the heating cycle was 4000 ms.

[0078] The high-entropy single-atom catalyst prepared in the above tests was then subjected to electrochemical testing, as follows:

[0079] As an example, carbon cloth was used as a support electrode. Commercial carbon cloth was ultrasonically cleaned in water and ethanol for a few minutes to remove surface impurities, and then dried in an oven. A certain amount of catalyst powder, an appropriate amount of binder (Nafion), and a solvent (a mixture of ethanol and isopropanol) were mixed and mixed in an ultrasonic bath for 30 minutes until a uniform catalyst ink was formed. A certain amount of this homogeneous solution was dropped onto the cleaned carbon cloth, and after natural air drying, it was used for electrochemical testing. The test results are shown in Figure 4 Figure 4 As can be seen from Figure 4 , the corresponding overpotential of tests 1-4 at a current density of 50 mA cm -2 -2 was 275, 273, 275, and 291 mV, respectively, and the corresponding Tafel slope was 38, 31, 35, and 42 mV dec -1 , respectively. From the above test data, it can be seen that the prepared high-entropy single-atom catalyst sample has excellent electrocatalytic activity and fast reaction kinetics.

[0080] Through the above tests and tests, it can be seen that the rapid Joule heating method has significant advantages in the preparation of high-entropy single-atom catalysts:

[0081] (1) Simple preparation process, high efficiency, and low production cost: The rapid Joule heating process is relatively simple and does not require complex equipment and multi-step processing. Only the material needs to be placed between the carbon-based electrodes, and the Joule heat generated by the current is used for heating treatment, which is simple to operate. The material can be heated to a high temperature in a very short time (a few seconds or tens of seconds), significantly shortening the preparation time and improving the production efficiency. The preparation process does not require complex multiple equipment, only a ball mill and a flash heating device, reducing the cost of equipment and the difficulty of operation. During the preparation process, a large amount of solvent and chemical reagent is not required, reducing the generation of harmful waste and being friendly to the environment; this rapid treatment method greatly reduces energy consumption and production cost.

[0082] (2) Uniform molecular morphology of the catalyst: Traditional heating methods can easily lead to the agglomeration of metal atoms. The preparation method of the present application can achieve an extremely high temperature (usually more than 2000°C) in a short time, promoting the diffusion and uniform dispersion of metal atoms and ensuring the full mixing of multiple metal elements. Due to the characteristics of rapid heating and cooling, the metal atoms experience high temperature in a short time but do not stay at high temperature for a long time, reducing the agglomeration of metal atoms and maintaining the dispersed state of single atoms, so that the metal atoms are uniformly dispersed on the carbon substrate, forming a highly uniform single-atom structure; this uniform dispersion helps to expose more active sites and improve the catalytic performance of the catalyst.

[0083] ​(3) Good catalyst stability: The high-entropy single-atom catalyst is formed in a high-temperature environment and has high thermal stability and is not prone to structural changes. The uniform dispersion of the single-atom structure and the high-entropy effect together help to improve the service life and performance stability of the catalyst in actual applications.

[0084] (4) Wide application range of catalyst: The method is flexible in the selection of support materials and can be applied to various carbon-based materials and other high-temperature-resistant materials, thereby widening the application range of the high-entropy single-atom catalyst.

[0085] The high-entropy single-atom catalyst prepared in the embodiment can be widely applied to scenarios such as water electrolysis, fuel cells, and metal-air batteries.

[0086] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and the specification of the present application.

Claims

1. A method for the stabilized production of a high-entropy single-atom catalyst, characterized in that, The method comprises the following steps: Mixing the metal salt and the supporting substrate to prepare a mixed slurry by wet ball milling, wherein the wet ball milling comprises: mixing the supporting substrate and the metal salt, adding anhydrous ethanol and ammonia to form a uniform mixed solution; Adding the mixed solution into a ball milling tank, and then performing normal temperature ball milling and low temperature ball milling in an inert atmosphere; Freeze-drying the mixed slurry to obtain a dry powder; Treating the dry powder by a rapid Joule heat method to prepare a high-entropy single-atom catalyst.

2. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, The metal salt comprises any one of the following three: nitrate: iron nitrate Fe(NO3)3, nickel nitrate Ni(NO3)2, cobalt nitrate Co(NO3)2, copper nitrate Cu(NO3)2, manganese nitrate Mn(NO3)2, palladium nitrate Pd(NO3)2, platinum nitrate Pt(NO3)2; sulfate: ferrous sulfate FeSO4, nickel sulfate NiSO4, cobalt sulfate CoSO4, copper sulfate CuSO4, manganese sulfate MnSO4, platinum sulfate PtSO4, palladium sulfate PdSO4; acetate: iron acetate Fe(C2H3O2)2, nickel acetate Ni(C2H3O2)2, cobalt acetate Co(C2H3O2)2, copper acetate Cu(C2H3O2)2, manganese acetate Mn(C2H3O2)2, palladium acetate Pd(C2H3O2)2, platinum acetate Pt(C2H3O2)2.

3. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, The supporting substrate comprises a carbon substrate, and the carbon substrate comprises graphene, carbon nanotube, carbon black, glucose, melamine or urea.

4. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, The supporting substrate comprises a metal oxide substrate, and the metal oxide substrate comprises cerium oxide, silicon oxide or aluminum oxide.

5. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, When the wet ball milling is performed, the rotation speed of the ball mill is set to 300-500 rpm, the normal temperature ball milling time is 6-12 h, the low temperature ball milling time is 3-4 h, and the inert atmosphere is argon.

6. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, The freeze-drying comprises: freezing the mixed slurry, the freezing temperature is-4℃, the freezing time is 4 hours, and the mixed slurry is completely frozen; starting the freeze dryer, setting the vacuum degree to 10 Pa, the sublimation temperature to-20℃, and the sublimation time to 2 hours.

7. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 1, characterized in that, The rapid Joule heat method comprises: opening the vacuum box of the flash heat device, placing the dry powder on the heating material, after closing the vacuum box of the flash heat device, vacuumizing and then introducing inert gas, and then performing rapid Joule heat treatment on the dry powder according to the predetermined voltage, current, time and number of times.

8. The method for stabilizing and preparing a high-entropy single-atom catalyst according to claim 7, characterized in that, The electrode voltage is set to 15-40 V, the electrode current is set to 15-80 A, the time is set to 0.5-2 s, one heating cycle is 1.5-4 s, and the number of heating times is set to 5-10 times.

9. A high-entropy single-atom catalyst, characterized in that, The high-entropy single-atom catalyst is prepared by the preparation method in any one of claims 1-8.

10. The high-entropy single-atom catalyst in claim 9 is applied to electrolysis of water, fuel cells and metal-air batteries.

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