A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles

Abstract

This invention belongs to the field of nanomaterial preparation technology, specifically relating to a method for microwave-induced synthesis of ordered high-entropy nanoparticles. By leveraging the interaction between a microwave field and a multi-element metal precursor, the diffusion limitations of traditional high-temperature solid-state methods are overcome, achieving structural ordering and uniform elemental distribution in high-entropy nanoparticles. The metal precursor undergoes molecular polarization due to dielectric loss in the microwave field, achieving instantaneous molecular-level heating within the reaction system and overcoming the hysteresis of traditional heat conduction. Furthermore, the differences in dielectric constants between different metal ions result in a selective heating effect in the microwave field, promoting the simultaneous activation and atomic diffusion of 5-14 main metals in the high-entropy alloy. Under microwave conditions, the introduction of lattice defects provides more diffusion paths, further promoting atomic diffusion and ordering. The high-entropy nanoparticles synthesized using microwave induction are characterized by ordered structure, uniform composition, and small particle size.

Description

Technical Field

[0001] This invention belongs to the field of nanomaterial preparation technology, specifically relating to a method for microwave-induced synthesis of ordered high-entropy nanoparticles. Background Technology

[0002] Electrolysis of water for hydrogen production offers advantages such as zero carbon emissions and high hydrogen purity, making it the most promising hydrogen production technology currently available. However, both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in water electrolysis require overcoming high reaction energy barriers, resulting in high energy consumption. Utilizing single-component metal or binary alloy catalysts, such as those made of precious metal Pt, can lower the reaction energy barrier, reduce energy consumption, and improve water splitting efficiency; however, their high cost and resource scarcity limit their widespread application. Therefore, developing high-efficiency water electrolysis catalysts with low precious metal content is crucial for achieving large-scale application of water electrolysis for hydrogen production.

[0003] High-entropy nanoparticles have attracted widespread attention due to their multi-element composition, homogeneous solid solution structure, and large specific surface area. The synergistic effects of multiple elements in high-entropy nanoparticles provide diverse adsorption sites for multi-step tandem or multifunctional catalytic reactions, reducing the amount of noble metals required. However, the disordered atomic arrangement in high-entropy nanoparticles significantly limits the surface electronic structure and the selective exposure of active sites. Studies have shown that structurally ordered high-entropy intermetallic (HEI) nanomaterials with ultra-high activity crystal planes are rarely reported, mainly because the synthesis of HEI nanomaterials requires high temperatures to overcome the energy barrier of the disorder-to-order transition, inevitably leading to phase separation, surface deactivation, and abnormal growth of nanoparticles, resulting in reduced catalytic activity and stability. Therefore, the preparation of HEI nanocatalysts with high catalytic activity and excellent stability remains a bottleneck problem in this field. Summary of the Invention

[0004] To address the problems in existing technologies, this invention provides a method for microwave-induced synthesis of ordered high-entropy nanoparticles. The prepared high-entropy nanoparticles are small-sized, well-dispersed, and structurally ordered FePt, FePd, CoPt, or AuCu-based high-entropy nanoparticles.

[0005] This invention overcomes the diffusion limitations of traditional high-temperature solid-state methods by leveraging the interaction between a microwave field and a multi-element metal precursor, achieving structural ordering and uniform elemental distribution in high-entropy nanoparticles. The metal precursor undergoes molecular polarization due to dielectric loss in the microwave field, achieving instantaneous molecular-level heating within the reaction system and overcoming the hysteresis of traditional heat conduction. Furthermore, the differences in dielectric constants between different metal ions result in selective heating effects in the microwave field, promoting the simultaneous activation and atomic diffusion of 5-14 main metals in the high-entropy alloy. Introducing lattice defects in a microwave environment provides more diffusion paths, further promoting atomic diffusion and ordering. The high-entropy nanoparticles synthesized using microwave-induced synthesis exhibit structural ordering, uniform composition, and small particle size. The project explores optimal microwave power, element types, reaction temperature, and reaction time for different components and particle types to achieve compositional and ordered structure control of high-entropy nanoparticles and establish structure-activity relationships between composition, size, and structure. The implementation of this project provides significant theoretical guidance for the development of efficient and low-cost nanocatalysts, offering a theoretical basis for developing HEI nanocatalysts with uniform composition and ordered structure.

[0006] The technical solution of this invention is:

[0007] A method for microwave-induced synthesis of ordered high-entropy nanoparticles includes the following steps:

[0008] (1) Add metal raw materials X, Y and M, reducing agent and solvent to the reaction vessel, mechanically stir and heat under protective gas conditions, raise the temperature to 100~120℃ at a heating rate of 1~10℃ / min and hold for 30~90min, then raise the temperature to 260~360℃ at a heating rate of 1~10℃ / min and hold for 1~10h, and cool to room temperature;

[0009] (2) Add centrifugal liquid 1 to the product of step (1), mix and centrifuge, pour off the upper layer, add centrifugal liquid 1 to the precipitate again, mix and repeat the centrifugation operation 3 to 6 times, obtain the precipitate and vacuum dry it to obtain black powder.

[0010] (3) Mix the black powder obtained in step (2) and the sintering aid evenly in a crucible, transfer it to a microwave oven, introduce protective gas, and evacuate the microwave oven to a vacuum level of 3×10⁻⁶. -4 ~3×10 -5 MPa, then heat with 600W~1000W microwave output power for 1~100min, and cool to room temperature;

[0011] (4) The product synthesized in step (3) was added to deionized water, ammonia water and centrifuge liquid 2 in sequence, mixed and centrifuged to finally obtain high-entropy nanoparticles with ordered structure.

[0012] Among them, raw materials X and Y are selected from two combinations of Fe, Pt, Pd, Co, Au, and Cu, and raw material M is selected from 3 to 12 elements selected from Mn, Zn, Co, Ni, Cu, Ru, Rh, Ir, Pd, Ce, Sm, Pr, Yb, Eu, Tl, Te, Th, Ag, Cd, In, Sn, Sb, Au, Hg, Pb, and Bi. The molar ratio of X, Y, and M is X:Y:M1:M2:…:M n The expression is (0.1~1.0):(0.1~1.0):(0.04~0.4):(0.04~0.4):…:(0.04~0.4), where 3≤n≤12.

[0013] Furthermore, in the aforementioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the combination of metal raw materials X and Y is Fe-Pt, Fe-Pd, Co-Pt, or Au-Cu; the Fe metal raw material involved is one of ferric acetylacetone, ferric chloride, or ferrous chloride; the Pt metal raw material is one of platinum acetylacetone, potassium tetrachloroplatinate, potassium hexachloroplatinate, ammonium tetrachloroplatinate, or chloroplatinic acid; the Pd metal raw material is one of palladium chloride, palladium acetylacetone, or palladium hexafluoroacetylacetone; the Co metal raw material is one of cobalt acetylacetone or cobalt chloride; the Au metal raw material is one of gold acetylacetone, gold chloride, or auric acid tetrachloride; the Cu metal raw material is one of copper acetylacetone or copper chloride; and the metal raw material M is one of an acetylacetone salt or a chloride salt.

[0014] Furthermore, in the above-mentioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the solvent in step (1) is oleylamine, triethanolamine oleate, or hexadecylamine, and the amount used is 10~60 ml; one of sodium bisulfite, sodium nitrite, sodium citrate, glucose, and ascorbic acid is used, and the molar ratio of the reducing agent to the metal raw material is 1.2~3.6.

[0015] Furthermore, in the above-mentioned microwave-induced synthesis of ordered high-entropy nanoparticles, the mechanical stirring speed in step (1) is 100~600 rpm / min.

[0016] Furthermore, in the above-mentioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the vacuum drying temperature in step (2) is 40~80℃, the time is 6~24h, the centrifugal liquid 1 is one of n-hexane, chloroform, acetone, and diethyl ether, the centrifugation speed is 1000~120000rpm / min, and the centrifugation time is 3~10min; in step (4), the centrifugal liquid 2 is one of ethanol, isopropanol, propanol, and cyclohexanol, the centrifugation speed is 1000~12000rpm / min, and the centrifugation time is 3~10min; the ratio of the amount of deionized water, ammonia water, and centrifugal liquid 2 added to the amount of synthetic product added is 1~50:1, 1~10:1, and 1~10:1, respectively, with the unit being ml:mg.

[0017] Furthermore, in the above-mentioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the protective gas is one of high-purity argon, high-purity nitrogen, high-purity helium, or a hydrogen-argon mixture, with an inlet flow rate of 60~600μL / min and an H2 content of 5% in the hydrogen-argon mixture.

[0018] Furthermore, in the above-mentioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the sintering aid in step (3) is boron oxide, sodium chloride, or lithium tetrafluoroborate, and the amount added is 1 to 100% of the mass of the black powder.

[0019] Furthermore, in the aforementioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, the high-entropy nanoparticles contain 5 to 14 main metals, have an average particle size of 2.0 to 20.0 nm, an order degree of 7.0 to 9.5, and a coercivity of 2000 to 8000 Oe.

[0020] Furthermore, in the above-mentioned method for microwave-induced synthesis of ordered high-entropy nanoparticles, in step (3), atomic-level ordered arrangement is achieved by adjusting the power and time during microwave heating, and the microwave frequency is coupled with the plasma resonance of the metal nanoparticle surface to drive lattice reconstruction.

[0021] The high-entropy nanoparticles prepared by the above method have a long-range ordered crystal structure and uniform elemental distribution.

[0022] The properties, morphology, and structure of the high-entropy nanoparticles were characterized using transmission electron microscopy (TEM). The size and morphology of the nanoparticles were observed using TEM HADDF mode and MAPING. The phase structure and order of the particles were tested using X-ray diffraction (XRD). The magnetic properties of the samples were tested using a vibrating sample magnetometer (VSM).

[0023] Advantages and beneficial effects of the present invention:

[0024] (1) Microwave dielectric heating technology achieves instantaneous heating and dynamic control of the reaction system through molecular-level energy transfer, significantly shortening the synthesis time while avoiding the thermal hysteresis of traditional high-temperature solid-state methods. The electric field polarization of the microwave field can precisely control the atomic diffusion dynamics, promote the orderly arrangement of multi-element metals, and ensure the rapid nucleation and uniform growth of high-entropy nanoparticles.

[0025] (2) Microwave-induced plasma resonance and dynamic confinement synergistically drive lattice reconstruction, achieving atomic-level homogeneous mixing of multiple principal metals (5-14 elements), effectively suppressing elemental segregation and phase separation. The resulting high-entropy nanoparticles have a long-range ordered crystal structure with significantly reduced lattice distortion, providing a structural basis for the high-temperature stability and catalytic activity of the material.

[0026] (3) The synergistic control of microwave power with temperature and time can be adapted to the phase transformation kinetics of different matrices (FePt, FePd, CoPt, AuCu), breaking through the limitations of traditional methods in controlling composition and structure. It provides experimental basis for the preparation of ordered transformation of high-entropy nanomaterials with complex configurations such as one-dimensional, core-shell, and heterostructure.

[0027] (4) By constructing the microwave-entropy-order structure-property relationship, high-entropy nanoparticles based on FePt, FePd, CoPt or AuCu with excellent magnetic properties, fine grains and high degree of order can be prepared. This invention not only promotes its practical application in the fields of next-generation magnetic storage media and electrocatalysts, but also provides a new idea and method for the preparation technology of high-entropy alloys. Attached Figure Description

[0028] Figure 1 TEM image (a) and high-magnification TEM image (b) of the structurally ordered high-entropy nanoparticles prepared in Example 1;

[0029] Figure 2 The particle size distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 1;

[0030] Figure 3 The elemental distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 1;

[0031] Figure 4 XRD patterns of the structurally ordered high-entropy nanoparticles prepared in Example 1;

[0032] Figure 5 VSM curves of the structurally ordered high-entropy nanoparticles prepared in Example 1;

[0033] Figure 6 TEM image (a) and high-magnification TEM image (b) of the structurally ordered high-entropy nanoparticles prepared in Example 2;

[0034] Figure 7 The particle size distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 2;

[0035] Figure 8 Elemental distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 2;

[0036] Figure 9 XRD patterns of the structurally ordered high-entropy nanoparticles prepared in Example 2;

[0037] Figure 10 VSM curves of the structurally ordered high-entropy nanoparticles prepared in Example 2. Detailed Implementation

[0038] This invention employs microwave-induced synthesis of structurally ordered high-entropy nanoparticles, which possess the functional characteristics of small particle size and high order. First, metallic raw materials, reducing agents, and solvents are added to a three-necked flask, heated to a specific temperature, and held for a certain time to obtain a high-entropy nanoparticle intermediate. This intermediate is then mixed with a sintering aid and transferred to a microwave oven for microwave-assisted heating treatment, yielding structurally ordered FePt, FePd, CoPt, or AuCu-based high-entropy nanoparticles. Under microwave conditions, the activation energy of atomic migration is lowered, preferentially forming ordered nuclei and promoting high-entropy ordering. Simultaneously, it suppresses elemental segregation caused by differences in Gibbs free energy in the high-entropy system. Furthermore, the microwave frequency resonates with the surface plasmon resonance of the metallic nanoparticles, generating a local electromagnetic field enhancement effect that drives atomic rearrangement to form an ordered structure, ultimately synthesizing high-order, highly coercive, and small-sized high-entropy nanoparticles.

[0039] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. Unless otherwise specified, the equipment, raw materials, pharmaceuticals, reagents, etc., involved in the following embodiments are all commercially available products. Example 1

[0040] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetonate and Platinum acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetonate salts with equimolar ratios of Co, Ni, Cu, Ru, and Ag elements. The molar ratio of metal raw materials X, Y, and M is 0.25:0.25:0.1:0.1:0.1:0.1:0.1. Subsequently, sodium bisulfite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.2, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity argon atmosphere at a stirring speed of 200 rpm / min. The temperature is increased to 110°C at a rate of 5°C / min and held for 60 min. Then, the temperature is increased to 360°C at a rate of 3°C / min and held for 3 h. Finally, the temperature is cooled to room temperature.

[0041] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 5 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 60°C for 24 hours to obtain a black powder.

[0042] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 100 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 300 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -5 Heat at 850W microwave output power for 60 minutes at MPa, then cool to room temperature.

[0043] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 10:1, ammonia to synthesized sample was 6:1, and ethanol to synthesized sample was 3:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 6000 rpm and a centrifugation time of 8 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0044] TEM observation of nanoparticles revealed good uniformity in morphology and size, as shown in the attached figure. Figure 1 As shown in (a); by measuring the interplanar spacing of the particles as 0.271 nm, corresponding to L The (110) crystal plane of 10-FePt, as shown in the attached image. Figure 1 As shown in (b). Subsequently, the particle size distribution was statistically analyzed as shown in the attached figure. Figure 2 As shown, the average particle size of the nanoparticles was 5.78 nm. The elemental distribution of the particles was observed using TEM in HADDF mode and MAPING, as shown in the attached figure. Figure 3 As shown, each element is distributed on the particle. The phase structure of the particle determined by XRD is shown in the attached figure. Figure 4 As shown, diffraction peaks were found to be... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.85. Finally, the magnetic properties of the sample were tested using VSM, as shown in the attached figure. Figure 5 As shown, the coercivity of the high-entropy nanoparticles is 2582 Oe. These results confirm the synthesis of highly ordered, highly coercive, and fine-sized high-entropy nanoparticles. Example 2

[0045] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetonate and Platinum acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of acetylacetonate salts of Co, Ni, Cu, and Ru in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.5:0.5:0.2:0.2:0.2:0.2. Subsequently, sodium nitrite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 3.6, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity nitrogen at a speed of 300 rpm / min. The temperature is increased to 115°C at a rate of 8°C / min and held for 90 min. Then, the temperature is increased to 340°C at a rate of 5°C / min and held for 3 h. The mixture is then cooled to room temperature.

[0046] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 6000 rpm for 9 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0047] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 50 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 200 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 4 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated at 800W microwave output power for 70 minutes, and then cooled to room temperature.

[0048] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 50:1, ammonia to synthesized sample was 10:1, and ethanol to synthesized sample was 10:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugation tests, with a centrifugation speed of 12000 rpm and a centrifugation time of 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0049] TEM observation of nanoparticles revealed good uniformity in morphology and size, as shown in the attached figure. Figure 6 As shown in (a); by measuring the interplanar spacing of the particles as 0.270 nm, corresponding to L The (110) crystal plane of 10-FePt, as shown in the attached image. Figure 6 As shown in (b). Subsequently, the particle size distribution was statistically analyzed as shown in the attached figure. Figure 7As shown, the average particle size of the nanoparticles was 6.52 nm. The elemental distribution of the particles was observed using TEM in HADDF mode and MAPING, as shown in the attached figure. Figure 8 As shown, each element is distributed on the particle. The phase structure of the particle determined by XRD is shown in the attached figure. Figure 9 As shown, diffraction peaks were found to be... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.90. Finally, the magnetic properties of the sample were tested using VSM, as shown in the attached figure. Figure 10 As shown, the coercivity of the high-entropy nanoparticles is 2631 Oe. These results confirm the synthesis of high-entropy nanoparticles with high order, high coercivity, and small size. Example 3

[0050] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetone and Platinum acetylacetone are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetone salts with equimolar ratios of Co, Ni, Cu, Ru, and Ag elements. The molar ratio of metal raw materials X, Y, and M is 1.0:1.0:0.4:0.4:0.4:0.4:0.4. Subsequently, sodium citrate (reducing agent) and oleylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.4, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity helium at a stirring speed of 100 rpm / min. The temperature is increased to 105°C at a rate of 10°C / min, held for 30 min, then increased to 320°C at a rate of 4°C / min, held for 3 h, and finally cooled to room temperature.

[0051] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 10,000 rpm for 4 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 80°C for 12 hours to obtain a black powder.

[0052] The black powder and sintering aid lithium tetrafluoroborate were mixed evenly and placed in a crucible. The amount of sintering aid added was 1 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity helium gas was introduced at a flow rate of 100 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 80 minutes with a microwave output power of 750W, and then cooled to room temperature.

[0053] The synthesized sample was added sequentially to deionized water, ammonia, and propanol, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 5:1, and propanol to synthesized sample was 5:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 8000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0054] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 6.49 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.90. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 6000 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 4

[0055] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and potassium tetrachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Mn, Zn, Co, Rh, and Cd in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.1:0.1:0.04:0.04:0.04:0.04:0.04. Subsequently, reducing agent glucose and solvent oleylamine are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.5, and the solvent is 10-60 ml. Mechanical stirring is performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 600 rpm / min. The temperature is increased to 100℃ at a rate of 3℃ / min, held for 45 min, then increased to 300℃ at a rate of 10℃ / min, held for 8 h, and finally cooled to room temperature.

[0056] Add 1% chloroform to the three-necked flask after the reaction, mix well, and centrifuge at 4000 rpm for 8 minutes. Discard the supernatant, add 1% chloroform to the precipitate and mix well. Repeat the above centrifugation operation 5 times to obtain the precipitate. Vacuum dry the precipitate at 50°C for 15 hours to obtain a black powder.

[0057] The black powder and sintering aid boron oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 60 wt.% of the black powder. The mixture was then transferred to a microwave oven, and a hydrogen-argon mixture (5% H2) was introduced at a flow rate of 60 μL / min. The outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 6 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 100 minutes with a microwave output power of 600W, and then cooled to room temperature.

[0058] The synthesized sample was added sequentially to deionized water, ammonia, and cyclohexanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 30:1, ammonia to synthesized sample was 6:1, and cyclohexanol to synthesized sample was 7:1 (all in ml:mg). The centrifugation parameters were the same for all three centrifugation cycles: 1000 rpm / min for 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0059] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 13.26 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated order degree of 0.93. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 7100 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 5

[0060] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and potassium hexachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Mn, Zn, Ni, Ir, and In in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.3:0.3:0.12:0.12:0.12:0.12:0.12. Subsequently, ascorbic acid (reducing agent) and triethanolamine oleate (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.6, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity argon atmosphere at a stirring speed of 400 rpm / min. The temperature is increased to 120°C at a rate of 2°C / min and held for 60 min. Then, the temperature is increased to 320°C at a rate of 8°C / min and held for 1 h. The mixture is then cooled to room temperature.

[0061] Add 1 acetone to the three-necked flask after the reaction, mix well, and centrifuge at 12000 rpm for 3 minutes. Discard the supernatant, add 1 acetone to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 70°C for 16 hours to obtain a black powder.

[0062] The black powder and sintering aid calcium hydride were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.5 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 600 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated at 850W microwave output power for 40 minutes, and then cooled to room temperature.

[0063] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 50:1, ammonia to synthesized sample was 10:1, and ethanol to synthesized sample was 1:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugation cycles: 12000 rpm / min for 3 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0064] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 16.21 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated order degree of 0.92. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 6300 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 6

[0065] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and ammonium tetrachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Mn, Zn, Cu, Pd, and Sn in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.7:0.7:0.28:0.28:0.28:0.28:0.28. Subsequently, sodium bisulfite, a reducing agent, and triethanolamine oleate, a solvent, are weighed and added to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.4, and the solvent volume is 10-60 ml. Mechanical stirring is performed under high-purity nitrogen at a stirring speed of 500 rpm / min. The temperature is increased to 110°C at a rate of 1°C / min and held for 45 min. Then, the temperature is increased to 260°C at a rate of 7°C / min and held for 10 h. The mixture is then cooled to room temperature.

[0066] Add 1 part diethyl ether to the three-necked flask after the reaction, mix well, and centrifuge at 1000 rpm for 10 min. Discard the supernatant, add 1 part diethyl ether to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 80℃ for 17 h to obtain a black powder.

[0067] The black powder and sintering aid calcium oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 2.0 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 100 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 1 × 10⁻⁶. -4 The pressure was increased to MPa, then heated for 1 minute with a microwave output power of 1000W, and then cooled to room temperature.

[0068] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 1:1, the ratio of ammonia to synthesized sample was 5:1, and the ratio of ethanol to synthesized sample was 6:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation tests, with a centrifugation speed of 6000 rpm and a centrifugation time of 8 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0069] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 14.60 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... LThe 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.85. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3200 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 7

[0070] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and chloroplatinic acid are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Zn, Co, Ni, Ce, and Sb in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.5:0.5:0.20:0.20:0.20:0.20:0.20. Subsequently, sodium nitrite (reducing agent) and tetradecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.5, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity helium at a stirring speed of 200 rpm / min. The temperature is increased to 115°C at a rate of 5°C / min, held for 30 min, then increased to 280°C at a rate of 2°C / min, held for 8 h, and finally cooled to room temperature.

[0071] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 8 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0072] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 50 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 150 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated at 700W microwave output power for 60 minutes, and then cooled to room temperature.

[0073] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 5:1, ammonia to synthesized sample was 10:1, and ethanol to synthesized sample was 8:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 3000 rpm and a centrifugation time of 7 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0074] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 20.00 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 ordered structure characteristic peaks (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated order degree of 0.88. Finally, the magnetic properties of the nanoparticles were tested using VSM, revealing a coercivity of 8000 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 8

[0075] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferrous chloride and potassium tetrachloroplatinate are measured; then, metal raw material M is measured, which is composed of chloride salts of Zn, Co, Cu, Sm, and Au in equal molar ratios, and the molar ratio between metal raw materials X, Y, and M is 1.0:1.0:0.4:0.4:0.4:0.4:0.4. Subsequently, sodium citrate (reducing agent) and dioctadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw material is 3.0, and the solvent is 10-60 ml. Mechanical stirring is performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 300 rpm / min. The temperature is increased to 105°C at a rate of 8°C / min, held for 60 min, then increased to 360°C at a rate of 5°C / min, held for 3 h, and finally cooled to room temperature.

[0076] Add 1% chloroform to the three-necked flask after the reaction, mix well, and centrifuge at 6000 rpm for 6 minutes. Discard the supernatant, add 1% chloroform to the precipitate and mix well. Repeat the above centrifugation operation 5 times to obtain the precipitate. Vacuum dry the precipitate at 55°C for 18 hours to obtain a black powder.

[0077] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 80 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 180 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 900W, and then cooled to room temperature.

[0078] The synthesized sample was added sequentially to deionized water, ammonia, and propanol, and then centrifuged. The ratio of deionized water to synthesized sample was 15:1, ammonia to synthesized sample was 1:1, and propanol to synthesized sample was 10:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 5000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0079] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 12.16 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.90. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 5960 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 9

[0080] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferrous chloride and potassium hexachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Co, Ni, and Cu in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.1:0.1:0.04:0.04:0.04. Subsequently, sodium bisulfite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.2, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity argon atmosphere at a stirring speed of 200 rpm / min. The temperature is increased to 110°C at a rate of 5°C / min and held for 60 min. Then, the temperature is increased to 360°C at a rate of 3°C / min and held for 3 h. Finally, the temperature is cooled to room temperature.

[0081] Add 1 part diethyl ether to the three-necked flask after the reaction, mix well, and centrifuge at 5000 rpm for 5 minutes. Discard the supernatant, add 1 part diethyl ether to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 75°C for 24 hours to obtain a black powder.

[0082] The black powder and sintering aid lithium tetrafluoroborate were mixed evenly and placed in a crucible. The amount of sintering aid added was 10 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity helium gas was introduced at a flow rate of 80 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated at 700W microwave output power for 45 minutes, and then cooled to room temperature.

[0083] The synthesized sample was added sequentially to deionized water, ammonia, and cyclohexanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 20 ml, ammonia to synthesized sample was 8:1, and cyclohexanol to synthesized sample was 5:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation trials, with a centrifugation speed of 1000 rpm and a centrifugation time of 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0084] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 5.67 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.95. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3200 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 10

[0085] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferrous chloride and chloroplatinic acid are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Co, Ni, and Ru in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.6:0.6:0.24:0.24:0.24. Subsequently, sodium nitrite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 3.6, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity nitrogen at a speed of 300 rpm / min. The temperature is increased to 115°C at a rate of 8°C / min and held for 90 min. Then, the temperature is increased to 340°C at a rate of 5°C / min and held for 3 h. The mixture is then cooled to room temperature.

[0086] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 5 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 60°C for 24 hours to obtain a black powder.

[0087] The black powder and sintering aid boron oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 40 wt.% of the black powder. The mixture was then transferred to a microwave oven, and a hydrogen-argon mixture (5% H2) was introduced at a flow rate of 100 μL / min. The outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum of 7 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 100 minutes with a microwave output power of 600W, and then cooled to room temperature.

[0088] The synthesized sample was added sequentially to deionized water, ammonia, and isopropanol, and then centrifuged. The ratio of deionized water to synthesized sample was 8:1, ammonia to synthesized sample was 10:1, and isopropanol to synthesized sample was 1:1. All units are ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 8000 rpm and a centrifugation time of 6 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0089] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 5.71 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.93. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 6240 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 11

[0090] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetonate and palladium acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of acetylacetonate salts of Co, Ni, and Ir in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.8:0.8:0.32:0.32:0.32. Subsequently, sodium citrate (reducing agent) and oleylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.4, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity helium at a speed of 100 rpm / min. The temperature is increased to 105°C at a rate of 10°C / min, held for 30 min, then increased to 320°C at a rate of 4°C / min, held for 3 h, and finally cooled to room temperature.

[0091] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 6000 rpm for 9 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0092] The black powder and sintering aid calcium hydride were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.2 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 60 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 1 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 750W, and then cooled to room temperature.

[0093] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 10:1, ammonia to synthesized sample was 6:1, and ethanol to synthesized sample was 5:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 8000 rpm and a centrifugation time of 8 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0094] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 4.56 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... LThe 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated order degree of 0.91. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3025 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 12

[0095] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and palladium chloride are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Ni, Cu, and Ru in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.4:0.4:0.16:0.16:0.16. Subsequently, glucose as a reducing agent and oleylamine as a solvent are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.5, and the solvent is 10-60 ml. Mechanical stirring is performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 600 rpm / min. The temperature is increased to 100°C at a rate of 3°C / min, held for 45 min, then increased to 300°C at a rate of 10°C / min, held for 8 h, and finally cooled to room temperature.

[0096] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 10,000 rpm for 4 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 80°C for 12 hours to obtain a black powder.

[0097] The black powder and sintering aid calcium oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.4 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 90 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 2 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated for 100 minutes with a microwave output power of 600W, and then cooled to room temperature.

[0098] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 50:1, ammonia to synthesized sample was 10:1, and ethanol to synthesized sample was 6:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugation cycles: 6000 rpm / min for 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0099] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 6.52 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 ordered structure characteristic peaks (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.70. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 2000 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 13

[0100] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and palladium hexafluoroacetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Co, Cu, and Rh elements in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.6:0.6:0.24:0.24:0.24. Subsequently, ascorbic acid (reducing agent) and triethanolamine oleate (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.6, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity argon atmosphere at a stirring speed of 400 rpm / min. The temperature is increased to 120°C at a rate of 2°C / min and held for 60 min. Then, the temperature is increased to 320°C at a rate of 8°C / min and held for 1 h, followed by cooling to room temperature.

[0101] Add 1% chloroform to the three-necked flask after the reaction, mix well, and centrifuge at 4000 rpm for 8 minutes. Discard the supernatant, add 1% chloroform to the precipitate and mix well. Repeat the above centrifugation operation 5 times to obtain the precipitate. Vacuum dry the precipitate at 50°C for 15 hours to obtain a black powder.

[0102] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 70 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 300 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 8 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 700W, and then cooled to room temperature.

[0103] The synthesized sample was added sequentially to deionized water, ammonia, and propanol, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 5:1, and propanol to synthesized sample was 10:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation tests, with a centrifugation speed of 8000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0104] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 4.94 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 ordered structure characteristic peaks (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.92. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 2478 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 14

[0105] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferrous chloride and palladium chloride are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Ni, Cu, and Rh elements in an equimolar ratio. The molar ratio of metal raw materials X, Y, and M is 0.8:0.8:0.32:0.32:0.32. Subsequently, sodium bisulfite, a reducing agent, and triethanolamine oleate, a solvent, are weighed and added to a three-necked flask, wherein the molar ratio of the reducing agent to the metal raw materials is 2.4, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity nitrogen at a stirring speed of 500 rpm / min. The temperature is increased to 110°C at a rate of 1°C / min, held for 45 min, then increased to 260°C at a rate of 7°C / min, held for 10 h, and finally cooled to room temperature.

[0106] Add 1 acetone to the three-necked flask after the reaction, mix well, and centrifuge at 12000 rpm for 3 minutes. Discard the supernatant, add 1 acetone to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 70°C for 16 hours to obtain a black powder.

[0107] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 90 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 200 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 5 minutes with a microwave output power of 950W, before cooling to room temperature.

[0108] The synthesized sample was added sequentially to deionized water, ammonia, and cyclohexanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 30:1, ammonia to synthesized sample was 8:1, and cyclohexanol to synthesized sample was 7:1 (all in ml:mg). The centrifugation parameters were the same for all three centrifugation trials: 5000 rpm / min for 10 min. The resulting black powder was high-entropy nanoparticles with an ordered structure.

[0109] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 2.00 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.90. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 2000 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 15

[0110] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Cobalt acetylacetonate and platinum acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetonate salts of Mn, Zn, Cd, Ni, Cu, Ru, Rh, Ir, Pd, Ag, Au, and Bi in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.4:0.4:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16. Subsequently, sodium nitrite (reducing agent) and tetradecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.5, and the solvent is 10-60 ml. Mechanical stirring was performed under high-purity helium conditions at a stirring speed of 200 rpm / min. The temperature was increased to 115°C at a rate of 5°C / min, held for 30 min, then increased to 280°C at a rate of 2°C / min, held for 8 h, and finally cooled to room temperature.

[0111] Add 1 part diethyl ether to the three-necked flask after the reaction, mix well, and centrifuge at 1000 rpm for 10 min. Discard the supernatant, add 1 part diethyl ether to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 80℃ for 17 h to obtain a black powder.

[0112] The black powder and sintering aid lithium tetrafluoroborate were mixed evenly and placed in a crucible. The amount of sintering aid added was 25 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity helium gas was introduced at a flow rate of 100 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 800W, and then cooled to room temperature.

[0113] The synthesized sample was added sequentially to deionized water, ammonia, and isopropanol, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 2:1, and isopropanol to synthesized sample was 1:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 12000 rpm and a centrifugation time of 3 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0114] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 19.14 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.93. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 2672 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 16

[0115] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Cobalt chloride and chloroplatinic acid are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Mn, Zn, Ru, Ni, Cu, Sm, Pr, Yb, Eu, Sb, Au, and Hg in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.5:0.5:0.20:0.20:0.20:0.20:0.20:0.20:0.20:0.20:0.20:0.20:0.20:0.20. Subsequently, sodium citrate (reducing agent) and dioctadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw material is 3.0, and the solvent is 10-60 ml. Mechanical stirring was performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 300 rpm / min. The temperature was increased to 105°C at a rate of 8°C / min and held for 60 min. Then, the temperature was increased to 360°C at a rate of 5°C / min and held for 3 h. Finally, the temperature was cooled to room temperature.

[0116] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 8 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0117] The black powder and sintering aid boron oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 30 wt.% of the black powder. The mixture was then transferred to a microwave oven, and a hydrogen-argon mixture (5% H2) was introduced at a flow rate of 60 μL / min. The outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 6 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 5 minutes with a microwave output power of 1000W, and then cooled to room temperature.

[0118] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuge liquid 2, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 25:1, ammonia to synthesized sample was 5:1, and ethanol to synthesized sample was 2:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 6000 rpm and a centrifugation time of 8 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0119] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 16.67 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 ordered structure characteristic peaks (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.92. Finally, the magnetic properties of the nanoparticles were tested using VSM, revealing a coercivity of 6371 Oe. These results confirm the synthesis of highly ordered, highly coercive, and fine-sized high-entropy nanoparticles. Example 17

[0120] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Gold acetylacetone and copper acetylacetone are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetone salts of Mn, Zn, Co, Ni, Rh, Ru, Tl, Te, Th, Hg, Pb, and Bi in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.2:0.2:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08. Subsequently, sodium bisulfite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.2, and the solvent is 10-60 ml. Mechanical stirring was performed under high-purity argon atmosphere at a stirring speed of 200 rpm / min. The temperature was increased to 110°C at a rate of 5°C / min and held for 60 min. Then, the temperature was increased to 360°C at a rate of 3°C / min and held for 3 h. Finally, the temperature was cooled to room temperature.

[0121] Add 1% chloroform to the three-necked flask after the reaction, mix well, and centrifuge at 6000 rpm for 6 minutes. Discard the supernatant, add 1% chloroform to the precipitate and mix well. Repeat the above centrifugation operation 5 times to obtain the precipitate. Vacuum dry the precipitate at 55°C for 18 hours to obtain a black powder.

[0122] The black powder and sintering aid calcium hydride were mixed evenly and placed in a crucible. The amount of sintering aid added was 1 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 600 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 1 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 750W, and then cooled to room temperature.

[0123] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 15:1, the ratio of ammonia to synthesized sample was 8:1, and the ratio of ethanol to synthesized sample was 6:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation tests, with a centrifugation speed of 4000 rpm and a centrifugation time of 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0124] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 17.91 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.85. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3267 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 18

[0125] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Gold chloride and copper chloride are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Co, Ni, Zn, Ru, Rh, and Ir in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.4:0.4:0.16:0.16:0.16:0.16:0.16:0.16. Subsequently, sodium nitrite (reducing agent) and hexadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 3.6, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity nitrogen at a stirring speed of 300 rpm / min. The temperature is increased to 115°C at a rate of 8°C / min and held for 90 min. Then, the temperature is increased to 340°C at a rate of 5°C / min and held for 3 h. The mixture is then cooled to room temperature.

[0126] Add 1 part diethyl ether to the three-necked flask after the reaction, mix well, and centrifuge at 5000 rpm for 5 minutes. Discard the supernatant, add 1 part diethyl ether to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 75°C for 24 hours to obtain a black powder.

[0127] The black powder and sintering aid calcium oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.2 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 100 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 2 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated for 10 minutes with a microwave output power of 1000W, and then cooled to room temperature.

[0128] The synthesized sample was added sequentially to deionized water, ammonia, and propanol, and then centrifuged. The ratio of deionized water to synthesized sample was 11:1, ammonia to synthesized sample was 6:1, and propanol to synthesized sample was 10:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 5000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0129] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 20.00 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.88. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3517 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 19

[0130] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Auronic acid tetrachloride and copper chloride are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Co, Ni, Zn, Ru, Rh, and Pd in ​​equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.7:0.7:0.28:0.28:0.28:0.28:0.28:0.28. Subsequently, sodium citrate (reducing agent) and oleylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.4, and the solvent is 10-60 ml. Mechanical stirring is performed under high-purity helium at a stirring speed of 100 rpm / min. The temperature is increased to 105°C at a rate of 10°C / min, held for 30 min, then increased to 320°C at a rate of 4°C / min, held for 3 h, and finally cooled to room temperature.

[0131] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 5 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 60°C for 24 hours to obtain a black powder.

[0132] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 50 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 150 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 20 minutes with a microwave output power of 700W, and then cooled to room temperature.

[0133] The synthesized sample was added sequentially to deionized water, ammonia, and cyclohexanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 20 ml, ammonia to synthesized sample was 7:1, and cyclohexanol to synthesized sample was 5:1 (all units are ml:mg). The centrifugation parameters were the same for all three centrifugation cycles: 7000 rpm / min and 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0134] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 18.54 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.90. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3478 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 20

[0135] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetonate and Platinum acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetonate salts with equimolar ratios of Co, Cu, Ru, Rh, Ir, Ag, and Au elements. The molar ratio of metal raw materials X, Y, and M is 0.8:0.8:0.32:0.32:0.32:0.32:0.32:0.32:0.32. Subsequently, reducing agent glucose and solvent oleylamine are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.5, and the solvent is 10-60 ml. Mechanical stirring is performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 600 rpm / min. The temperature is increased to 100℃ at a rate of 3℃ / min, held for 45 min, then increased to 300℃ at a rate of 10℃ / min, held for 8 h, and finally cooled to room temperature.

[0136] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 6000 rpm for 9 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0137] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 80 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 180 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 30 minutes with a microwave output power of 750W, and then cooled to room temperature.

[0138] The synthesized sample was added sequentially to deionized water, ammonia, and isopropanol, and then centrifuged. The ratio of deionized water to synthesized sample was 8:1, ammonia to synthesized sample was 10:1, and isopropanol to synthesized sample was 3:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 6000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0139] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 18.16 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... LThe 10 ordered structure characteristic peaks (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.95. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 7428 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 21

[0140] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric acetylacetonate and Platinum acetylacetonate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of acetylacetonate salts of Mn, Co, Ni, Rh, Ir, Pd, Hg, Pb, and Bi in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.3:0.3:0.12:0.12:0.12:0.12:0.12:0.12:0.12:0.12. Subsequently, the reducing agent ascorbic acid and the solvent triethanolamine oleate are weighed and added to a three-necked flask, wherein the molar ratio of the reducing agent to the metal raw materials is 1.6, and the solvent is 10-60 ml. Mechanical stirring was performed under high-purity argon atmosphere at a stirring speed of 400 rpm / min. The temperature was increased to 120°C at a rate of 2°C / min and held for 60 min. Then, the temperature was increased to 320°C at a rate of 8°C / min and held for 1 h. Finally, the temperature was cooled to room temperature.

[0141] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 10,000 rpm for 4 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 80°C for 12 hours to obtain a black powder.

[0142] The black powder and sintering aid potassium carbonate were mixed evenly and placed in a crucible. The amount of sintering aid added was 10 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity helium gas was introduced at a flow rate of 80 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 5 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 20 minutes with a microwave output power of 800W, and then cooled to room temperature.

[0143] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 10:1, ammonia to synthesized sample was 6:1, and ethanol to synthesized sample was 3:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 6000 rpm and a centrifugation time of 8 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0144] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 13.49 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.93. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 5417 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 22

[0145] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and potassium tetrachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Mn, Co, Ni, Rh, Ir, Pd, Hg, Pb, and Bi in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.1:0.1:0.04:0.04:0.04:0.04:0.04:0.04:0.04:0.04:0.04. Subsequently, sodium bisulfite, a reducing agent, and triethanolamine oleate, a solvent, are weighed and added to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.4, and the solvent volume is 10-60 ml. Mechanical stirring was performed under high-purity nitrogen atmosphere at a stirring speed of 500 rpm / min. The temperature was increased to 110℃ at a rate of 1℃ / min and held for 45 min. Then, the temperature was increased to 260℃ at a rate of 7℃ / min and held for 10 h. Finally, the temperature was cooled to room temperature.

[0146] Add 1% chloroform to the three-necked flask after the reaction, mix well, and centrifuge at 4000 rpm for 8 minutes. Discard the supernatant, add 1% chloroform to the precipitate and mix well. Repeat the above centrifugation operation 5 times to obtain the precipitate. Vacuum dry the precipitate at 50°C for 15 hours to obtain a black powder.

[0147] The black powder and sintering aid boron oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 40 wt.% of the black powder. The mixture was then transferred to a microwave oven, and a hydrogen-argon mixture (5% H2) was introduced at a flow rate of 100 μL / min. The outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated for 15 minutes with a microwave output power of 850W, and then cooled to room temperature.

[0148] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2 ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 50:1, ammonia to synthesized sample was 10:1, and ethanol to synthesized sample was 10:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugation tests, with a centrifugation speed of 12000 rpm and a centrifugation time of 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0149] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 13.73 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.92. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 5371 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 23

[0150] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and potassium hexachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured. Metal raw material M is composed of chloride salts of Zn, Co, Ni, Cu, Ru, Rh, Ir, Ce, Sm, and Ag in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.4:0.4:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16:0.16. Subsequently, sodium nitrite (reducing agent) and tetradecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 2.5, and the solvent is 10-60 ml. Mechanical stirring was performed under high-purity helium conditions at a stirring speed of 200 rpm / min. The temperature was increased to 115°C at a rate of 5°C / min, held for 30 min, then increased to 280°C at a rate of 2°C / min, held for 8 h, and finally cooled to room temperature.

[0151] Add 1 acetone to the three-necked flask after the reaction, mix well, and centrifuge at 12000 rpm for 3 minutes. Discard the supernatant, add 1 acetone to the precipitate and mix well. Repeat the above centrifugation operation 6 times to obtain the precipitate. Vacuum dry the precipitate at 70°C for 16 hours to obtain a black powder.

[0152] The black powder and sintering aid calcium hydride were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.2 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity argon gas was introduced at a flow rate of 60 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 2 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated at 750W microwave output power for 60 minutes, and then cooled to room temperature.

[0153] The synthesized sample was added sequentially to deionized water, ammonia, and propanol, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 5:1, and propanol to synthesized sample was 5:1. All units were ml:mg. The centrifugation parameters were the same for all three centrifugation cycles, with a centrifugation speed of 8000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0154] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 15.15 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated order degree of 0.95. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 3258 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 24

[0155] This embodiment describes a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Ferric chloride and ammonium tetrachloroplatinate are measured as metal raw materials X and Y, respectively. Then, metal raw material M is measured, consisting of chloride salts of Co, Ni, and Cu in equimolar ratios. The molar ratio of metal raw materials X, Y, and M is 0.5:0.5:0.20:0.20:0.20. Subsequently, sodium citrate (reducing agent) and dioctadecylamine (solvent) are weighed and added to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 3.0, and the solvent is 10-60 ml. Mechanical stirring is performed under a hydrogen-argon mixture (5% H2) at a stirring speed of 300 rpm / min. The temperature is increased to 105°C at a rate of 8°C / min and held for 60 min. Then, the temperature is increased to 360°C at a rate of 5°C / min and held for 3 h. Finally, the temperature is cooled to room temperature.

[0156] Add 1 part diethyl ether to the three-necked flask after the reaction, mix well, and centrifuge at 1000 rpm for 10 min. Discard the supernatant, add 1 part diethyl ether to the precipitate and mix well. Repeat the above centrifugation operation 3 times to obtain the precipitate. Vacuum dry the precipitate at 80℃ for 17 h to obtain a black powder.

[0157] The black powder and sintering aid calcium oxide were mixed evenly and placed in a crucible. The amount of sintering aid added was 1.4 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 90 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 1 × 10⁻⁶. -4 The pressure was increased to MPa, and then heated for 20 minutes with a microwave output power of 850W, before cooling to room temperature.

[0158] The synthesized sample was added sequentially to deionized water, ammonia, and cyclohexanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 8:1, and cyclohexanol to synthesized sample was 10:1 (all in ml:mg). The centrifugation parameters were the same for all three centrifugation cycles: 6000 rpm / min for 10 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0159] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 13.51 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... LThe 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.93. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 2478 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles. Example 25

[0160] This embodiment discloses a method for microwave-induced synthesis of ordered high-entropy nanoparticles, specifically including the following steps: Measure iron acetylacetonate and platinum acetylacetonate as metal raw materials X and Y, respectively. Then measure metal raw material M, which is composed of acetylacetonate salts of Mn, Zn, Co, Ni, Cu, Sm, Pr, Yb, Eu, Sb, Au, and Hg in equal molar ratios. The molar ratio of metal raw materials X, Y, and M is 0.2:0.2:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08:0.08. Subsequently, weigh sodium bisulfite (reducing agent) and hexadecylamine (solvent) and add them to a three-necked flask, wherein the molar ratio of reducing agent to metal raw materials is 1.2, and the solvent is 10-60 ml. Mechanical stirring was performed under high-purity argon atmosphere at a stirring speed of 200 rpm / min. The temperature was increased to 110°C at a rate of 5°C / min and held for 60 min. Then, the temperature was increased to 360°C at a rate of 3°C / min and held for 3 h. Finally, the temperature was cooled to room temperature.

[0161] Add 1 part hexane to the three-necked flask after the reaction, mix well, and centrifuge at 8000 rpm for 8 minutes. Discard the supernatant, add 1 part hexane to the precipitate and mix well. Repeat the above centrifugation operation 4 times to obtain the precipitate. Vacuum dry the precipitate at 40°C for 24 hours to obtain a black powder.

[0162] The black powder and sintering aid sodium chloride were mixed evenly and placed in a crucible. The amount of sintering aid added was 100 wt.% of the black powder. The mixture was then transferred to a microwave oven, and high-purity nitrogen gas was introduced at a flow rate of 100 μL / min. The gas outlet and inlet valves were then closed, and the diffusion pump was started to evacuate the microwave oven to a vacuum level of 3 × 10⁻⁶. -5 The pressure was increased to MPa, and then heated at 700W microwave output power for 60 minutes, and then cooled to room temperature.

[0163] The synthesized sample was added sequentially to deionized water, ammonia, and centrifuged liquid 2-ethanol, mixed thoroughly, and then centrifuged. The ratio of deionized water to synthesized sample was 20:1, ammonia to synthesized sample was 5:1, and ethanol to synthesized sample was 5:1, all in ml:mg. The centrifugation parameters were the same for all three centrifugations, with a centrifugation speed of 12000 rpm and a centrifugation time of 5 min. The final black powder obtained was high-entropy nanoparticles with an ordered structure.

[0164] TEM observation of the nanoparticles revealed good uniformity in morphology and size; the average particle size was 15.62 nm. HADDF-MAPING characterization of the elemental distribution of the nanoparticles showed that all elements were distributed on the particles. XRD analysis of the phase structure of the particles revealed that the diffraction peaks were consistent with... L The 10 characteristic peaks of the ordered structure (PDF#43-1359) correspond one-to-one, indicating that the synthesized nanoparticles possess a high degree of order, with a calculated orderness of 0.92. Finally, the magnetic properties of the nanoparticles were tested using VSM, and their coercivity was 4231 Oe. These results confirm the synthesis of high-order, high-coercivity, small-sized, high-entropy nanoparticles.

[0165] As can be seen from the above embodiments, the high-entropy nanoparticles synthesized by microwave induction of the present invention exhibit excellent ordered structure, high coercivity and small particle size, and the nanoparticles have uniform element distribution and good morphological and size uniformity.

Claims

1. A method for microwave-induced synthesis of ordered high-entropy nanoparticles, characterized in that, Includes the following steps: (1) Add metal raw materials X, Y and M, reducing agent and solvent to the reaction vessel, mechanically stir and heat under protective gas conditions, raise the temperature to 100~120℃ at a heating rate of 1~10℃ / min and hold for 30~90min, then raise the temperature to 260~360℃ at a heating rate of 1~10℃ / min and hold for 1~10h, and cool to room temperature; (2) Add centrifugal liquid 1 to the product of step (1), mix and centrifuge, pour off the upper layer, add centrifugal liquid 1 to the precipitate again, mix and repeat the centrifugation operation 3 to 6 times, obtain the precipitate and vacuum dry it to obtain black powder. (3) Mix the black powder obtained in step (2) and the sintering aid evenly in a crucible, transfer it to a microwave oven, introduce protective gas, and evacuate the microwave oven to a vacuum level of 3×10⁻⁶. -4 ~3×10 -5 MPa, then heat with 600W~1000W microwave output power for 1~100min, and cool to room temperature; (4) The product synthesized in step (3) was added to deionized water, ammonia water and centrifuge liquid 2 in sequence, mixed and centrifuged to finally obtain high-entropy nanoparticles with ordered structure. Among them, raw materials X and Y are selected from two combinations of Fe, Pt, Pd, Co, Au, and Cu, and raw material M is selected from 3 to 12 elements selected from Mn, Zn, Co, Ni, Cu, Ru, Rh, Ir, Pd, Ce, Sm, Pr, Yb, Eu, Tl, Te, Th, Ag, Cd, In, Sn, Sb, Au, Hg, Pb, and Bi. The molar ratio of X, Y, and M is X:Y:M1:M2:…:M n The expression is (0.1~1.0):(0.1~1.0):(0.04~0.4):(0.04~0.4):…:(0.04~0.4), where 3≤n≤12.

2. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, The combination of metal raw materials X and Y is Fe-Pt, Fe-Pd, Co-Pt, or Au-Cu; the Fe metal raw material involved is one of ferric acetylacetone, ferric chloride, or ferrous chloride; the Pt metal raw material is one of platinum acetylacetone, potassium tetrachloroplatinate, potassium hexachloroplatinate, ammonium tetrachloroplatinate, or chloroplatinic acid; the Pd metal raw material is one of palladium chloride, palladium acetylacetone, or palladium hexafluoroacetylacetone; the Co metal raw material is one of cobalt acetylacetone or cobalt chloride; the Au metal raw material is one of gold acetylacetone, gold chloride, or auric acid tetrachloride; the Cu metal raw material is one of copper acetylacetone or copper chloride; and the metal raw material M is one of an acetylacetone salt or a chloride salt.

3. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, The solvent mentioned in step (1) is oleylamine, triethanolamine oleate or hexadecylamine, and the amount used is 10~60ml; the reducing agent is one of sodium bisulfite, sodium nitrite, sodium citrate, glucose or ascorbic acid, and the molar ratio of the reducing agent to the metal raw material is 1.2~3.

6.

4. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, In step (1), the mechanical stirring speed is 100~600 rpm / min.

5. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, Step (2) Vacuum drying temperature is 40~80℃, time is 6~24h, centrifuge liquid 1 is one of n-hexane, chloroform, acetone, and diethyl ether, centrifugation speed is 1000~120000rpm / min, centrifugation is 3~10min; Step (4) Centrifuge liquid 2 is one of ethanol, isopropanol, propanol, and cyclohexanol, centrifugation speed is 1000~12000rpm / min, centrifugation is 3~10min; the ratio of deionized water, ammonia water, centrifuge liquid 2 to the amount of synthetic product added is 1~50:1, 1~10:1 and 1~10:1 respectively, unit is ml:mg.

6. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, The protective gas is one of high-purity argon, high-purity nitrogen, high-purity helium, or a hydrogen-argon mixture, with an inlet flow rate of 60~600μL / min and an H2 content of 5% in the hydrogen-argon mixture.

7. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, The sintering aid mentioned in step (3) is boron oxide, sodium chloride or lithium tetrafluoroborate, and the amount added is 1 to 100% of the mass of the black powder.

8. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, The high-entropy nanoparticles contain 5 to 14 main metals, with an average particle size of 2.0 to 20.0 nm, an order degree of 7.0 to 9.5, and a coercivity of 2000 to 8000 Oe.

9. The method for microwave-induced synthesis of ordered high-entropy nanoparticles according to claim 1, characterized in that, In step (3), atomic-level ordered arrangement is achieved by adjusting the power and time during microwave heating, and the microwave frequency is coupled with the plasma resonance of the metal nanoparticle surface to drive lattice reconstruction.

10. A high-entropy nanoparticle prepared by the method of any one of claims 1-9, characterized in that, It has a long-range ordered crystal structure and uniform element distribution.

Images