Method for synthesizing ordered-structure high-entropy nanoparticles through microwave induction

Abstract

The invention belongs to the technical field of nano material preparation, and particularly relates to a method for synthesizing ordered-structure high-entropy nano particles through microwave induction. Through interaction of a microwave field and a multi-element metal precursor, diffusion limitation of a traditional high-temperature solid-phase method is broken through, and structure ordering and element uniform distribution of the high-entropy nanoparticles are achieved. The metal precursor generates molecular polarization in a microwave field due to dielectric loss, so that molecular-level instantaneous temperature rise in a reaction system is realized, and the hysteresis of traditional heat conduction is overcome. In addition, different metal ions generate a selective heating effect in a microwave field due to the difference of dielectric constants, and synchronous activation and atomic diffusion of 5-14 kinds of principal element metal in the high-entropy alloy are promoted. In a microwave environment, more diffusion paths can be provided by introducing lattice defects, so that diffusion and ordering of atoms are promoted. The high-entropy nanoparticles synthesized by microwave induction have the characteristics of ordered structure, uniform components and small particle size.

Description

Technical Field

[0001] The present invention belongs to the technical field of nanomaterial preparation, and particularly relates to a method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles. Background Art

[0002] Hydrogen production by electrolyzing water has the advantages of zero carbon emission and high hydrogen production purity, and is currently the most promising hydrogen production technology. However, both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) of electrolyzing water need to overcome relatively high reaction energy barriers, resulting in high electrolysis energy consumption. Using single-component metals or binary alloy catalysts represented by noble metal Pt can reduce the reaction energy barrier, reduce energy consumption, and improve the water decomposition efficiency. However, the high price and scarce resources limit their wide application. Therefore, developing electrolysis water catalysts with low noble metal content and high efficiency is the key to realizing large-scale application of hydrogen production by electrolyzing water.

[0003] High-entropy nanoparticles have received extensive attention due to their advantages such as multi-element composition, uniformly mixed solid solution structure, and large specific surface area. The multi-element synergistic effect in high-entropy nanoparticles provides different adsorption sites for multi-step tandem or multifunctional catalytic reactions and reduces the usage amount of noble metals. However, due to the disordered atomic arrangement in high-entropy nanoparticles, it greatly limits the surface electronic structure and selectively exposes active sites. Research shows that ordered-structured high-entropy intermetallic compound (HEI) nanomaterials with ultra-high active crystal planes are rarely reported, mainly because the synthesis of HEI nanomaterials requires high temperature to overcome the energy barrier for the transformation from disorder to order, inevitably leading to phase separation of nanoparticles, loss of surface activity, and abnormal growth, resulting in reduced catalytic activity and stability. Therefore, preparing HEI nanocatalysts with high catalytic activity and excellent stability has always been a bottleneck problem in this field. Summary of the Invention

[0004] Aiming at the problems in the prior art, the present invention provides a method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles. The prepared high-entropy nanoparticles are fine-particle-sized, well-dispersed, and ordered-structured FePt, FePd, CoPt, or AuCu-based high-entropy nanoparticles.

[0005] Through the interaction between the microwave field and the multi-metal precursor, the present invention breaks through the diffusion limitation of the traditional high-temperature solid-phase method, realizing the structural ordering and uniform element distribution of high-entropy nanoparticles. The metal precursor generates molecular polarization due to dielectric loss in the microwave field, achieving instantaneous internal molecular-level heating in the reaction system and overcoming the hysteresis of traditional heat conduction. In addition, due to the difference in dielectric constants of different metal ions, a selective heating effect is generated in the microwave field, promoting the synchronous activation and atomic diffusion of 5-14 main element metals in the high-entropy alloy. In a microwave environment, by introducing lattice defects, more diffusion paths can be provided, thereby promoting atomic diffusion and ordering. The high-entropy nanoparticles synthesized by microwave induction have the characteristics of ordered structure, uniform composition, and small particle size. By exploring the reasonable microwave power, element types, reaction temperature, and reaction time of particles with different components and compositions, the composition and ordered structure of high-entropy nanoparticles can be regulated, and the structure-activity relationship between composition-size-structure can be established. The implementation of this project has important theoretical guiding significance for the development of efficient and low-cost nanocatalysts, providing a theoretical basis for the development of HEI nanocatalysts with uniform composition and ordered structure.

[0006] The technical solution of the present invention is as follows: A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles, comprising the following steps: (1) Add metal raw materials X, Y, and M, a reducing agent, and a solvent into a reaction vessel, perform mechanical stirring and heating under a protective gas condition, heat at a heating rate of 1-10 °C / min to 100-120 °C and keep warm for 30-90 min, then heat at a heating rate of 1-10 °C / min to 260-360 °C and keep warm for 1-10 h, and cool to room temperature; (2) Add centrifugate 1 to the product of step (1), mix well and centrifuge, pour off the upper layer liquid, add centrifugate 1 to the precipitate again, mix well, and repeat the centrifugation operation 3-6 times. Obtain the precipitate and perform vacuum drying to obtain a black powder; (3) Mix the black powder obtained in step (2) and a sintering aid evenly, place them in a crucible, transfer them into a microwave oven, introduce a protective gas, evacuate the microwave oven to 3×10 -4 ~3×10 -5 MPa, then heat at a microwave output power of 600W-1000W for 1-100 min, and cool to room temperature; (4) Add the synthesis product of step (3) to deionized water, ammonia water, and centrifugate 2 in sequence, mix well and centrifuge to finally obtain ordered structure high-entropy nanoparticles; Among them, raw materials X and Y are selected from a combination of two of Fe, Pt, Pd, Co, Au, and Cu, and raw material M is selected from 3 to 12 of the elements 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, and the molar ratio of X:Y:M1:M2:…:M n 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.

[0007] Furthermore, for the above method for microwave-induced synthesis of ordered-structured 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 iron acetylacetonate, ferric chloride, and ferrous chloride, the Pt metal raw material is one of platinum acetylacetonate, potassium tetrachloroplatinate, potassium hexachloroplatinate, ammonium tetrachloroplatinate, and chloroplatinic acid, the Pd metal raw material is one of palladium chloride, palladium acetylacetonate, and hexafluoroacetylacetonato palladium, the Co metal raw material is one of cobalt acetylacetonate and cobalt chloride, the Au metal raw material is one of gold acetylacetonate, gold chloride, and chloroauric acid, and the Cu metal raw material is one of copper acetylacetonate and copper chloride; the metal raw material M is one of acetylacetonate salts and chloride salts.

[0008] Furthermore, for the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the solvent in step (1) is oleylamine, triethanolamine oleate, or hexadecylamine, and the dosage is 10~60 ml; one of sodium bisulfite, sodium nitrite, sodium citrate, glucose, and ascorbic acid, and the molar ratio of the reducing agent to the metal raw material is 1.2~3.6.

[0009] Furthermore, for the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the mechanical stirring speed in step (1) is 100~600 rpm / min.

[0010] Furthermore, for the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the vacuum drying temperature in step (2) is 40~80 °C, the time is 6~24 h, the centrifugation liquid 1 is one of n-hexane, chloroform, acetone, and ether, and the centrifugation speed is 1000~120000 rpm / min, and the centrifugation time is 3~10 min; the centrifugation liquid 2 in step (4) is one of ethanol, isopropanol, propanol, and cyclohexanol, the centrifugation speed is 1000~12000 rpm / min, and the centrifugation time is 3~10 min; the addition amounts of deionized water, ammonia water, and centrifugation liquid 2 to the addition amount of the synthesis product are 1~50:1, 1~10:1, and 1~10:1 respectively, with the unit of ml:mg.

[0011] Further, in the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the protective gas is one of high-purity argon, high-purity nitrogen, high-purity helium, and hydrogen-argon mixture, and the flow rate is 60-600 μL / min, and the H2 content in the hydrogen-argon mixture is 5%.

[0012] Further, in the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the sintering aid in step (3) is boron oxide, sodium chloride, or lithium tetrafluoroborate, and the addition amount is 1-100% of the mass of the black powder.

[0013] Further, in the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, the high-entropy nanoparticles contain 5-14 main element metals, the average particle size is 2.0-20.0 nm, the degree of order is 7.0-9.5, and the coercivity is 2000-8000 Oe.

[0014] Further, in the above method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles, during microwave heating in step (3), atomic-level ordered arrangement is achieved by regulating the power and time, and the microwave frequency is coupled with the surface plasmon resonance of metal nanoparticles to drive lattice reconstruction.

[0015] The high-entropy nanoparticles prepared by the above method have a long-range ordered crystal structure and uniform element distribution.

[0016] For the performance, morphology, and structure characterization of the above high-entropy nanoparticles, a transmission electron microscope (TEM) is used to observe the size and morphology of the nanoparticles, the HADDF mode and MAPING of the TEM are used to observe the element / composition distribution of the particles, an X-ray diffractometer (XRD) is used to test the phase structure and order of the particles, and a vibrating sample magnetometer (VSM) is used to test the magnetic properties of the samples.

[0017] Advantages and beneficial effects of the present invention: (1) The microwave dielectric heating technology realizes the instantaneous temperature rise and dynamic regulation of the reaction system through molecular-level energy transfer, significantly shortens the synthesis time, and at the same time avoids the thermal hysteresis of the traditional high-temperature solid-phase method. The electric field polarization of the microwave field can accurately regulate the atomic diffusion kinetics, promote the ordered arrangement of multi-metal elements, and ensure the rapid nucleation and uniform growth of high-entropy nanoparticles.

[0018] (2) The microwave-induced plasma resonance effect and the dynamic confinement effect synergistically drive lattice reconstruction to achieve atomic-level uniform mixing of multi-principal element metals (5-14 elements), effectively suppressing element segregation and phase separation. The obtained high-entropy nanoparticles have a long-range ordered crystal structure with a significantly reduced lattice distortion degree, providing a structural basis for the high-temperature stability and catalytic activity of the material.

[0019] (3) The multi-factor synergistic regulation of microwave power, temperature, and time can adapt to the phase transformation kinetic characteristics of different substrates (FePt, FePd, CoPt, AuCu), breaking through the limitations of traditional methods that are difficult to control the components and composition. It provides an experimental basis for the preparation method of the ordered transformation of high-entropy nanomaterials with complex configurations such as one-dimensional, core-shell, and heterojunctions.

[0020] (4) By constructing the microwave-entropy-order structure-activity relationship, high-entropy nanoparticles based on FePt, FePd, CoPt, or AuCu with excellent magnetic properties, fine grains, and high order can be controllably prepared. The present invention not only promotes their practical application in the fields of new-generation magnetic storage media, electrocatalysts, etc., but also provides a new idea and method for the preparation technology of high-entropy alloys. Description of the Drawings

[0021] Figure 1 TEM images (a) and high-magnification TEM images (b) of the structurally ordered high-entropy nanoparticles prepared in Example 1; Figure 2 Particle size distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 1; Figure 3 Element distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 1; Figure 4 XRD pattern of the structurally ordered high-entropy nanoparticles prepared in Example 1; Figure 5 VSM curve of the structurally ordered high-entropy nanoparticles prepared in Example 1; Figure 6 TEM images (a) and high-magnification TEM images (b) of the structurally ordered high-entropy nanoparticles prepared in Example 2; Figure 7 Particle size distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 2; Figure 8 Element distribution diagram of the structurally ordered high-entropy nanoparticles prepared in Example 2; Figure 9 XRD pattern of the structurally ordered high-entropy nanoparticles prepared in Example 2; Figure 10 VSM curve of the structurally ordered high-entropy nanoparticles prepared in Example 2. Detailed implementation mode

[0022] The present invention uses microwave-induced synthesis to prepare structurally ordered high-entropy nanoparticles, which have the functional characteristics of small particle size and high order. First, metal raw materials, reducing agents, and solvents are added to a three-necked flask, and the temperature is raised to a certain temperature and kept for a certain time to obtain high-entropy nanoparticle intermediates. Then, the mixture of sintering aids is transferred into a microwave oven and treated under microwave-assisted heating to obtain structurally ordered FePt, FePd, CoPt, or AuCu-based high-entropy nanoparticles. In a microwave environment, by reducing the activation energy of atomic migration, ordered nuclei are preferentially formed to promote high-entropy ordering. At the same time, it also inhibits the element segregation caused by the Gibbs free energy difference in the high-entropy system. In addition, the microwave frequency is coupled with the surface plasmon resonance of metal nanoparticles, generating a local electromagnetic field enhancement effect, driving atomic rearrangement to form an ordered structure, and finally synthesizing high-entropy nanoparticles with high order, high coercivity, and small size.

[0023] The present invention will be further described in detail below with reference to the accompanying drawings of the specification and embodiments. For the equipment, raw materials, drugs, reagents, etc. involved in the following embodiments, unless otherwise specified, they are all commercially available products purchased on the market. Example 1

[0024] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this example specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate as X and Y metal raw materials respectively, and then measure M metal raw materials, where M metal raw materials are composed of acetylacetonate salts of Co, Ni, Cu, Ru, Ag elements in an equimolar ratio, and the molar ratio between X, Y, and M metal raw materials is 0.25:0.25:0.1:0.1:0.1:0.1:0.1. Subsequently, weigh the reducing agent sodium bisulfite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 1.2, and the solvent is 10 - 60 ml. Mechanical stirring is carried out under high-purity argon conditions, and the mechanical stirring speed is 200 rpm / min. The temperature is raised to 110°C at a heating rate of 5°C / min and kept for 60 min, then the temperature is raised to 360°C at a heating rate of 3°C / min and kept for 3 h, and then cooled to room temperature.

[0025] Add centrifugate 1 n-hexane to the three-necked flask after the reaction, mix them evenly, and then centrifuge using a centrifuge at a centrifugation speed of 8000 rpm / min for 5 min. Pour off the upper layer liquid, add centrifugate 1 n-hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 3 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 60°C, and the drying time is 24 h to obtain a black powder.

[0026] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 100 wt.% of the black powder. Then transfer the mixture into a microwave oven, and introduce high-purity argon at a flow rate of 300 μL / min. Subsequently, close the outlet and inlet valves, start the diffusion pump to evacuate the vacuum, and evacuate the vacuum in the microwave oven to 3×10 -5 MPa. With a microwave output power of 850 W, heat for 60 min, and then cool to room temperature.

[0027] Add the synthesized sample to deionized water, ammonia water, and centrifuged liquid 2 ethanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 10:1, the addition amount of ammonia water to the synthesized sample is 6:1, and the addition amount of ethanol to the synthesized sample is 3:1. The units are all ml:mg. The three centrifugation parameters are the same, where the centrifugation speed is 6000 rpm / min and the centrifugation time is 8 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles.

[0028] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good, as shown in Figure 1 (a); By measuring the interplanar spacing of the particles to be 0.271 nm, corresponding to the (110) crystal plane of L 10-FePt, as shown in Figure 1 (b). Subsequently, the size distribution of the particles was statistically analyzed as shown in Figure 2 shown, and the average particle size of the nanoparticles was obtained as 5.78 nm. Using the HADDF mode and MAPING of TEM to observe the element distribution of the particles as shown in Figure 3 shown, it can be seen that each element is distributed on the particles. Using XRD to test the phase structure of the particles as shown in Figure 4 shown, it is found that the diffraction peaks correspond one by one to the L 10 ordered structure characteristic peaks (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.85. Finally, use VSM to test the magnetic properties of the sample as shown in Figure 5 shown, and the coercivity of the high-entropy nanoparticles is 2582 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 2

[0029] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate as X and Y metal raw materials respectively, and then measure M metal raw materials. The M metal raw materials are composed of acetylacetonate salts of Co, Ni, Cu, Ru elements in equimolar ratio. The molar ratio between X, Y and M metal raw materials is 0.5:0.5:0.2:0.2:0.2:0.2. Subsequently, weigh the reducing agent sodium nitrite and the solvent hexadecylamine and add them into a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 3.6, and the solvent is 10 - 60 ml. Under the condition of high-purity nitrogen, carry out mechanical stirring. The mechanical stirring speed is 300 rpm / min. Heat to 115 °C at a heating rate of 8 °C / min, keep warm for 90 min, then heat to 340 °C at a heating rate of 5 °C / min, keep warm for 3 h, and cool to room temperature.

[0030] Add n-hexane of centrifugate 1 to the three-necked flask after the reaction, mix them evenly and then use a centrifuge for centrifugation. The centrifugation speed is 6000 rpm / min, and the centrifugation time is 9 min. Pour off the upper layer liquid. Add n-hexane of centrifugate 1 to the precipitate and mix them evenly. Repeat the above centrifugation operation 6 times. Carry out vacuum drying on the obtained precipitate. The vacuum drying temperature is 40 °C, and the drying time is 24 h to obtain a black powder.

[0031] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 50 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, introduce high-purity nitrogen at a flow rate of 200 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, pump the vacuum in the microwave oven to 4×10 -5 MPa, and then heat at a microwave output power of 800 W for 70 min, and then cool to room temperature.

[0032] Add the synthesized sample to deionized water, ammonia water, and ethanol of centrifugate 2 in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 50:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of ethanol to the synthesized sample is 10:1. The unit is ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 12000 rpm / min, and the centrifugation time is 10 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0033] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good, as shown in Figure 6 (a); By measuring the crystal plane spacing of the particles to be 0.270 nm, corresponding to the (110) crystal plane of 10-FePt, as shown in L (b). Subsequently, the size distribution of the particles was statistically analyzed as shown in Figure 6 (b). Then, the size distribution of the particles was counted as shown in Figure 7As shown, the average particle size of the nanoparticles was obtained as 6.52 nm. The elemental distribution of the particles was observed using the HADDF mode and MAPING of TEM as shown in the appendix Figure 8 As shown, it can be seen that each element is distributed on the particles. The phase structure of the particles was tested using XRD as shown in the appendix Figure 9 As shown, it was found that the diffraction peaks corresponded one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of order. After calculation, the degree of order was 0.90. Finally, the magnetic properties of the sample were tested using VSM as shown in the appendix Figure 10 As shown, the coercivity of the high-entropy nanoparticles was 2631 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 3

[0034] A method for microwave-induced synthesis of high-entropy nanoparticles with ordered structure in this example specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of acetylacetonate salts of Co, Ni, Cu, Ru, Ag elements with an equimolar ratio. The molar ratio between X, Y, and M metal raw materials is 1.0:1.0:0.4:0.4:0.4:0.4:0.4. Subsequently, weigh the reducing agent sodium citrate and the solvent oleylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 2.4, and the solvent is 10 - 60 ml. Under the condition of high-purity helium gas, mechanical stirring is carried out at a mechanical stirring speed of 100 rpm / min. The temperature is raised to 105 °C at a heating rate of 10 °C / min and kept warm for 30 min, then the temperature is raised to 320 °C at a heating rate of 4 °C / min and kept warm for 3 h, and then cooled to room temperature.

[0035] Add centrifugate 1 n-hexane to the three-necked flask after the reaction, mix them evenly, and then use a centrifuge for centrifugation at a centrifugation speed of 10000 rpm / min for 4 min. Pour off the upper layer liquid, add centrifugate 1 n-hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 4 times, and perform vacuum drying on the obtained precipitate. The vacuum drying temperature is 80 °C and the drying time is 12 h to obtain a black powder.

[0036] Mix the black powder and the sintering aid lithium tetrafluoroborate evenly and place them in a crucible. The addition amount of the sintering aid is 1 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high-purity helium gas at a flow rate of 100 μL / min, then close the outlet and inlet valves, start the diffusion pump to pump vacuum, pump the vacuum in the microwave oven to 5×10 -5 MPa, and then heat at a microwave output power of 750 W for 80 min, and then cool to room temperature.

[0037] The synthesized sample was successively added with deionized water, ammonia water, and centrifugate 2-propanol, mixed evenly, and then centrifuged. The addition amount of deionized water to the synthesized sample was 20:1, the addition amount of ammonia water to the synthesized sample was 5:1, and the addition amount of 2-propanol to the synthesized sample was 5:1. The unit was ml:mg. The centrifugation parameters were the same for 3 times. The centrifugation speed was 8000 rpm / min, and the centrifugation time was 5 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0038] Using TEM to observe the nanoparticles, it was found that the particle morphology and size uniformity were good; the average particle size of the nanoparticles was 6.49 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it was found that each element was distributed on the particles. Using XRD to test the phase structure of the particles, it was found that the diffraction peaks L corresponded one by one to the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of ordered structure. After calculation, the degree of order was 0.90. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity was 6000 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 4

[0039] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this example specifically includes the following steps: Measure ferric chloride and potassium tetrachloroplatinate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material is composed of chlorides of Mn, Zn, Co, Rh, Cd elements with an equimolar ratio. The molar ratio between X, Y, and M metal raw materials is 0.1:0.1:0.04:0.04:0.04:0.04:0.04. Subsequently, weigh the reducing agent glucose and the solvent oleylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 1.5, and the solvent is 10 - 60 ml. Under the condition of a hydrogen-argon mixed gas (5% H2), mechanical stirring is carried out. The mechanical stirring speed is 600 rpm / min. The temperature is raised to 100 °C at a heating rate of 3 °C / min, held for 45 min, and then the temperature is raised to 300 °C at a heating rate of 10 °C / min and held for 8 h, and then cooled to room temperature.

[0040] Add centrifugate 1 chloroform to the three-necked flask after the reaction, mix it evenly, and then centrifuge it using a centrifuge. The centrifugation speed is 4000 rpm / min, and the centrifugation time is 8 min. Pour off the upper layer liquid, add centrifugate 1 chloroform to the precipitate and mix it evenly. Repeat the above centrifugation operation 5 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 50 °C, and the drying time is 15 h to obtain a black powder.

[0041] Mix the black powder and the sintering aid boron oxide evenly and place them in a crucible. The addition amount of the sintering aid is 60 wt.% of the black powder. Then transfer the mixture into a microwave oven, and introduce a hydrogen-argon mixture (5% H2) at a flow rate of 60 μL / min. Subsequently, close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 6×10 -5 MPa. Then, with a microwave output power of 600 W, heat for 100 min, and then cool to room temperature.

[0042] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 cyclohexanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 30:1, the addition amount of ammonia water to the synthesized sample is 6:1, and the addition amount of cyclohexanol to the synthesized sample is 7:1. The units are all ml:mg. The three centrifugation parameters are the same. Among them, the centrifugation speed is 1000 rpm / min, and centrifuge for 10 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0043] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 13.26 nm. Use HADDF-MAPING to characterize the element distribution of the nanoparticles, and it is found that each element is distributed on the particles. Use XRD to test the phase structure of the particles, and it is found that the diffraction peaks correspond one by one to L the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.93. Finally, use VSM to test the magnetic properties of the nanoparticles, and its coercivity is 7100 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 5

[0044] A method for microwave-induced synthesis of high-entropy nanoparticles with an ordered structure in this example specifically includes the following steps: Measure ferric chloride and potassium hexachloroplatinate as the X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material is composed of chlorides of Mn, Zn, Ni, Ir, In elements with an equimolar ratio. The molar ratio between the X, Y and M metal raw materials is 0.3:0.3:0.12:0.12:0.12:0.12:0.12. Subsequently, weigh the reducing agent ascorbic acid and the solvent triethanolamine oleate and add them to a three-necked flask. Among them, the molar ratio of the reducing agent to the metal raw material is 1.6, and the solvent is 10 - 60 ml. Carry out mechanical stirring under high-purity argon conditions. The mechanical stirring speed is 400 rpm / min. Raise the temperature to 120 °C at a heating rate of 2 °C / min, keep warm for 60 min, then raise the temperature to 320 °C at a heating rate of 8 °C / min, keep warm for 1 h, and then cool to room temperature.

[0045] Add centrifugate 1 acetone to the three-necked flask after the reaction. Mix it evenly and then centrifuge it using a centrifuge at a centrifugation speed of 12,000 rpm / min for 3 min. Pour off the supernatant. Add centrifugate 1 acetone to the precipitate and mix it evenly. Repeat the above centrifugation operation 6 times. Obtain the precipitate and conduct vacuum drying. The vacuum drying temperature is 70 °C and the drying time is 16 h to obtain a black powder.

[0046] Mix the black powder and the sintering aid calcium hydride evenly and place them in a crucible. The addition amount of the sintering aid is 1.5 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven and introduce high-purity argon at a flow rate of 600 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 3×10 -4 MPa. Then, with a microwave output power of 850 W, heat for 40 min, and then cool to room temperature.

[0047] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 ethanol in sequence. Mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 50:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of ethanol to the synthesized sample is 1:1. The unit is ml:mg. The centrifugation parameters for all 3 times are the same. The centrifugation speed is 12,000 rpm / min and the centrifugation time is 3 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0048] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 16.21 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks L correspond one by one to the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.92. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 6300 Oe. The above results confirm the synthesis of high-entropy nanoparticles with a high degree of order, high coercivity, and small size. Example 6

[0049] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure ferric chloride and ammonium tetrachloroplatinate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Mn, Zn, Cu, Pd, and Sn elements with an equimolar ratio. The molar ratio between the X, Y, and M metal raw materials is 0.7:0.7:0.28:0.28:0.28:0.28:0.28. Subsequently, weigh the reducing agent sodium bisulfite and the solvent triethanolamine oleate and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.4, and the solvent is 10 - 60 ml. Under the condition of high-purity nitrogen, perform mechanical stirring at a mechanical stirring speed of 500 rpm / min, heat to 110 °C at a heating rate of 1 °C / min, keep warm for 45 min, then heat to 260 °C at a heating rate of 7 °C / min, keep warm for 10 h, and cool to room temperature.

[0050] Add 1 ether of the centrifugate to the three-necked flask after the reaction, mix it evenly, and then centrifuge it using a centrifuge at a centrifugation speed of 1000 rpm / min for 10 min. Pour off the upper layer liquid, add 1 ether of the centrifugate to the precipitate and mix it evenly. Repeat the above centrifugation operation 3 times, and perform vacuum drying on the obtained precipitate. The vacuum drying temperature is 80 °C, and the drying time is 17 h to obtain a black powder.

[0051] Mix the black powder and the sintering aid calcium oxide evenly and place them in a crucible. The addition amount of the sintering aid is 2.0 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, introduce high-purity nitrogen at a flow rate of 100 μL / min, then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 1×10 -4 MPa, then heat at a microwave output power of 1000 W for 1 min, and then cool to room temperature.

[0052] Add the synthesized sample to deionized water, ammonia water, and 2 ethanol of the centrifugate in sequence, mix them evenly, and then centrifuge. The addition amount of deionized water to the synthesized sample is 1:1, the addition amount of ammonia water to the synthesized sample is 5:1, and the addition amount of ethanol to the synthesized sample is 6:1. The unit is ml:mg. The centrifugation parameters for all 3 times are the same, where the centrifugation speed is 6000 rpm / min and the centrifugation time is 8 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0053] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 14.60 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks are consistent with LThe characteristic peaks of the ordered structure (PDF#43-1359) correspond one by one, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.85. Finally, the magnetic properties of the nanoparticles were tested by VSM, and its coercivity is 3200 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 7

[0054] In this example, a method for microwave-induced synthesis of ordered structure high-entropy nanoparticles specifically includes the following steps: Measure ferric chloride and chloroplatinic acid as X and Y metal raw materials respectively, and then measure the M metal raw materials. The M metal raw materials are composed of chlorides of Zn, Co, Ni, Ce, Sb elements in equimolar ratio. The molar ratio between X, Y and M metal raw materials is 0.5:0.5:0.20:0.20:0.20:0.20:0.20. Subsequently, weigh the reducing agent sodium nitrite and the solvent tetradecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.5, and the solvent is 10-60 ml. Under the condition of high-purity helium gas, mechanical stirring is carried out, and the mechanical stirring speed is 200 rpm / min. The temperature is raised to 115 °C at a heating rate of 5 °C / min, held for 30 min, and then the temperature is raised to 280 °C at a heating rate of 2 °C / min and held for 8 h, and then cooled to room temperature.

[0055] Add centrifugate 1 n-hexane to the three-necked flask after the reaction, mix them evenly and then centrifuge with a centrifuge at a centrifugal speed of 8000 rpm / min for 8 min. Pour off the upper layer liquid, add centrifugate 1 n-hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 4 times, and vacuum-dry the obtained precipitate. The vacuum drying temperature is 40 °C and the drying time is 24 h to obtain black powder.

[0056] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 50 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high-purity argon at a flow rate of 150 μL / min, then close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 5×10 -5 MPa, and then heat at a microwave output power of 700 W for 60 min, and then cool to room temperature.

[0057] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 ethanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 5:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of ethanol to the synthesized sample is 8:1. The unit is ml:mg. The three centrifugation parameters are the same, with a centrifugal speed of 3000 rpm / min and a centrifugation time of 7 min. Finally, the obtained black powder is high-entropy nanoparticles with an ordered structure.

[0058] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 20.00 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks L correspond one by one to the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure, and the calculated degree of order is 0.88. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 8000 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 8

[0059] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure ferrous chloride and potassium tetrachloroplatinate; then measure the M metal raw material, and the M metal raw material is composed of chlorides of Zn, Co, Cu, Sm, Au elements with an equimolar ratio. The molar ratio between X, Y and the M metal raw material is 1.0:1.0:0.4:0.4:0.4:0.4:0.4. Subsequently, weigh the reducing agent sodium citrate and the solvent dioctadecylamine and add them to a three-necked flask, where the molar ratio of the reducing agent to the metal raw material is 3.0, and the solvent is 10-60 ml. Under the condition of a hydrogen-argon mixed gas (5% H2), carry out mechanical stirring, and the mechanical stirring speed is 300 rpm / min. Heat to 105 °C at a heating rate of 8 °C / min, keep warm for 60 min, then heat to 360 °C at a heating rate of 5 °C / min, keep warm for 3 h, and cool to room temperature.

[0060] Add chloroform of the centrifugate 1 to the reaction three-necked flask after the reaction, mix it evenly and then centrifuge it with a centrifuge. The centrifugation speed is 6000 rpm / min, and centrifuge for 6 min. Pour off the upper layer liquid, add chloroform of the centrifugate 1 to the precipitate and mix it evenly. Repeat the above centrifugation operation 5 times, and carry out vacuum drying on the obtained precipitate, where the vacuum drying temperature is 55 °C and the drying time is 18 h to obtain a black powder.

[0061] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 80 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high-purity nitrogen at a flow rate of 180 μL / min, then close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 3×10 -5 MPa, then heat at a microwave output power of 900 W for 30 min, and then cool to room temperature.

[0062] The synthesized sample was successively added with deionized water, ammonia water, and centrifugate 2-propanol, mixed evenly, and then centrifuged. The addition amount of deionized water to the synthesized sample was 15:1, the addition amount of ammonia water to the synthesized sample was 1:1, and the addition amount of propanol to the synthesized sample was 10:1, with the unit being ml:mg. The centrifugation parameters were the same for all 3 times, with a centrifugation speed of 5000 rpm / min and a centrifugation time of 5 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0063] TEM was used to observe the nanoparticles, and it was found that the particle morphology and size uniformity were good; the average particle size of the nanoparticles was 12.16 nm. HADDF-MAPING was used to characterize the elemental distribution of the nanoparticles, and it was found that all elements were distributed on the particles. XRD was used to test the phase structure of the particles, and it was found that the diffraction peaks corresponded one by one to L the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of ordered structure. After calculation, the degree of order was 0.90. Finally, VSM was used to test the magnetic properties of the nanoparticles, and its coercivity was 5960 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 9

[0064] In this example, a method for microwave-induced synthesis of ordered structure high-entropy nanoparticles specifically includes the following steps: Measure ferrous chloride and potassium hexachloroplatinate as the X and Y metal raw materials respectively, and then measure the M metal raw material, which is composed of chlorides of Co, Ni, Cu elements with an equimolar ratio. The molar ratio between the X, Y, and M metal raw materials is 0.1:0.1:0.04:0.04:0.04. Subsequently, weigh the reducing agent sodium bisulfite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 1.2, and the solvent is 10 - 60 ml. Mechanical stirring is carried out under high-purity argon conditions, with a mechanical stirring speed of 200 rpm / min. The temperature is raised to 110 °C at a heating rate of 5 °C / min and held for 60 min, then the temperature is raised to 360 °C at a heating rate of 3 °C / min and held for 3 h, and then cooled to room temperature.

[0065] Centrifugate 1 ether was added to the three-necked flask after the reaction, mixed evenly, and then centrifuged using a centrifuge at a centrifugation speed of 5000 rpm / min for 5 min. The upper layer liquid was poured off, and centrifugate 1 ether was added to the precipitate and mixed evenly. The above centrifugation operation was repeated 6 times, and the obtained precipitate was vacuum-dried, where the vacuum drying temperature was 75 °C and the drying time was 24 h to obtain a black powder.

[0066] Mix the black powder and the sintering aid lithium tetrafluoroborate evenly and place them in a crucible. The addition amount of the sintering aid is 10 wt.% of the black powder. Then transfer the mixture into a microwave oven, introduce high-purity helium gas at a flow rate of 80 μL / min, and then close the outlet and inlet valves. Start the diffusion pump to evacuate the air, and evacuate the microwave oven to 5×10 -5 MPa. Then, with a microwave output power of 700 W, heat for 45 min, and then cool to room temperature.

[0067] Add the synthesized sample to deionized water, ammonia water, and centrifugation liquid 2 cyclohexanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 20:1, the addition amount of ammonia water to the synthesized sample is 8:1, and the addition amount of cyclohexanol to the synthesized sample is 5:1. The units are all ml:mg. The three centrifugation parameters are the same. Among them, the centrifugation speed is 1000 rpm / min and the centrifugation time is 10 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles.

[0068] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 5.67 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks L correspond one by one to the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.95. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 3200 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 10

[0069] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure ferrous chloride and chloroplatinic acid as X and Y metal raw materials respectively, and then measure the M metal raw materials. The M metal raw materials are composed of chlorides of Co, Ni, Ru and other elements with equimolar ratios. The molar ratio between X, Y and M metal raw materials is 0.6:0.6:0.24:0.24:0.24. Then weigh the reducing agent sodium nitrite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 3.6, and the solvent is 10-60 ml. Under the condition of high-purity nitrogen, carry out mechanical stirring at a mechanical stirring speed of 300 rpm / min, heat up to 115 °C at a heating rate of 8 °C / min, keep warm for 90 min, then heat up to 340 °C at a heating rate of 5 °C / min, keep warm for 3 h, and cool to room temperature.

[0070] Add n-hexane of the centrifuged solution 1 to the three-necked flask after the reaction. Mix them evenly and then centrifuge using a centrifuge at a rotation speed of 8000 rpm / min for 5 min. Pour off the upper layer liquid. Add n-hexane of the centrifuged solution 1 to the precipitate and mix evenly. Repeat the above centrifugation operation 3 times. Vacuum dry the obtained precipitate at a temperature of 60 °C for 24 h to obtain a black powder.

[0071] Mix the black powder and sintering aid boron oxide evenly and place them in a crucible. The addition amount of the sintering aid is 40 wt.% of the black powder. Then transfer the mixture into a microwave oven and introduce a hydrogen-argon mixed gas (5% H2) at a flow rate of 100 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 7×10 -5 MPa. Then heat at a microwave output power of 600 W for 100 min and then cool to room temperature.

[0072] Add the synthesized sample to deionized water, ammonia water, and isopropyl alcohol of the centrifuged solution 2 in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 8:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of isopropyl alcohol to the synthesized sample is 1:1. The units are all ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 8000 rpm / min and the centrifugation time is 6 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0073] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 5.71 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks L correspond one by one to the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.93. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 6240 Oe. The above results confirm the synthesis of high-entropy nanoparticles with a high degree of order, high coercivity, and small size. Example 11

[0074] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure iron acetylacetonate and palladium acetylacetonate as X and Y metal raw materials respectively, and then measure the M metal raw material, which is composed of acetylacetonate salts of Co, Ni, Ir elements with an equimolar ratio. The molar ratio between the X, Y, and M metal raw materials is 0.8:0.8:0.32:0.32:0.32. Subsequently, weigh the reducing agent sodium citrate and the solvent oleylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 2.4, and the solvent is 10 - 60 ml. Mechanical stirring is carried out under high-purity helium gas conditions, the mechanical stirring speed is 100 rpm / min, the temperature is raised to 105 °C at a heating rate of 10 °C / min, held for 30 min, then the temperature is raised to 320 °C at a heating rate of 4 °C / min, held for 3 h, and then cooled to room temperature.

[0075] Add n-hexane of centrifugate 1 to the three-necked flask after the reaction, mix it evenly, and then centrifuge it using a centrifuge. The centrifugation speed is 6000 rpm / min, and the centrifugation time is 9 min. Pour off the upper layer liquid, add n-hexane of centrifugate 1 to the precipitate and mix it evenly. Repeat the above centrifugation operation 6 times, and vacuum-dry the obtained precipitate. The vacuum drying temperature is 40 °C, and the drying time is 24 h to obtain black powder.

[0076] Mix the black powder and the sintering aid calcium hydride evenly and place them in a crucible. The addition amount of the sintering aid is 1.2 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high-purity argon at a flow rate of 60 μL / min, then close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 1×10 -4 MPa, then heat it at a microwave output power of 750 W for 30 min, and then cool it to room temperature.

[0077] Add deionized water, ammonia water, and ethanol of centrifugate 2 to the synthesized sample in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 10:1, the addition amount of ammonia water to the synthesized sample is 6:1, and the addition amount of ethanol to the synthesized sample is 5:1. The unit is ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 8000 rpm / min, and the centrifugation time is 8 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0078] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 4.56 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks are consistent with LThe characteristic peaks of the ordered structure (PDF#43 - 1359) correspond one by one, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.91. Finally, the magnetic properties of the nanoparticles were tested by VSM, and its coercivity is 3025 Oe. The above results confirm the synthesis of high - entropy nanoparticles with high degree of order, high coercivity and small size. Example 12

[0079] A method for microwave - induced synthesis of ordered - structure high - entropy nanoparticles in this example specifically includes the following steps: Measure ferric chloride and palladium chloride as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Ni, Cu, Ru elements with an equimolar ratio. The molar ratio between X, Y and M metal raw materials is 0.4:0.4:0.16:0.16:0.16. Subsequently, weigh the reducing agent glucose and the solvent oleylamine and add them to a three - necked flask. The molar ratio of the reducing agent to the metal raw materials is 1.5, and the solvent is 10 - 60 ml. Under the condition of a hydrogen - argon mixture (5% H2), carry out mechanical stirring at a mechanical stirring speed of 600 rpm / min, heat up to 100 °C at a heating rate of 3 °C / min, keep warm for 45 min, then heat up to 300 °C at a heating rate of 10 °C / min, keep warm for 8 h, and cool to room temperature.

[0080] Add centrifugate 1 n - hexane to the three - necked flask after the reaction, mix them evenly and then use a centrifuge for centrifugation at a centrifugation speed of 10000 rpm / min for 4 min. Pour off the upper layer liquid, add centrifugate 1 n - hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 4 times, and vacuum - dry the obtained precipitate. The vacuum - drying temperature is 80 °C and the drying time is 12 h to obtain black powder.

[0081] Mix the black powder and the sintering aid calcium oxide evenly and place them in a crucible. The addition amount of the sintering aid is 1.4 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high - purity nitrogen at a flow rate of 90 μL / min, then close the outlet and inlet valves, start the diffusion pump to pump vacuum, pump the vacuum in the microwave oven to 2×10 -4 MPa, then heat at a microwave output power of 600 W for 100 min, and then cool to room temperature.

[0082] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 ethanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 50:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of ethanol to the synthesized sample is 6:1. The units are all ml:mg. The three centrifugation parameters are the same, where the centrifugation speed is 6000 rpm / min and the centrifugation time is 10 min. Finally, the obtained black powder is high - entropy nanoparticles with an ordered structure.

[0083] The TEM observation of the nanoparticles reveals that the particle morphology and size uniformity are relatively good; the average particle size of the nanoparticles is 6.52 nm. The HADDF-MAPING is used to characterize the elemental distribution of the nanoparticles, and it is found that each element is distributed on the particles. The XRD is used to test the phase structure of the particles, and it is found that the diffraction peaks correspond one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a relatively high ordered structure. After calculation, the degree of order is 0.70. Finally, the VSM is used to test the magnetic properties of the nanoparticles, and its coercivity is 2000 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 13

[0084] A method for microwave-induced synthesis of high-entropy nanoparticles with ordered structure in this example specifically includes the following steps: Measure ferric chloride and palladium hexafluoroacetylacetonate as the X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material is composed of chlorides of Co, Cu, Rh elements with an equimolar ratio. The molar ratio between the X, Y and M metal raw materials is 0.6:0.6:0.24:0.24:0.24. Subsequently, weigh the reducing agent ascorbic acid and the solvent triethanolamine oleate and add them into a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 1.6, and the solvent is 10 - 60 ml. Under the condition of high-purity argon, mechanical stirring is carried out, and the mechanical stirring speed is 400 rpm / min. The temperature is raised to 120 °C at a heating rate of 2 °C / min and kept warm for 60 min, then the temperature is raised to 320 °C at a heating rate of 8 °C / min and kept warm for 1 h, and then cooled to room temperature.

[0085] Add chloroform of centrifugate 1 to the three-necked flask after the reaction, mix them evenly and then use a centrifuge for centrifugation. The centrifugation speed is 4000 rpm / min and the centrifugation time is 8 min. Pour off the upper layer liquid, add chloroform of centrifugate 1 to the precipitate and mix them evenly. Repeat the above centrifugation operation 5 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 50 °C and the drying time is 15 h to obtain a black powder.

[0086] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 70 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, and introduce high-purity argon at a flow rate of 300 μL / min. Then close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 8×10 -5 MPa, and then heat at a microwave output power of 700 W for 30 min, and then cool to room temperature.

[0087] The synthesized sample was successively added with deionized water, ammonia water, and 2-propanol of the centrifugate, and after being mixed evenly, it was centrifuged. The addition amount of deionized water to the synthesized sample was 20:1, the addition amount of ammonia water to the synthesized sample was 5:1, and the addition amount of propanol to the synthesized sample was 10:1. The units were all ml:mg. The centrifugation parameters were the same for 3 times. Among them, the centrifugation speed was 8000 rpm / min, and the centrifugation time was 5 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0088] Observing the nanoparticles by TEM, it was found that the particle morphology and size had good uniformity; the average particle size of the nanoparticles was 4.94 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it was found that each element was distributed on the particles. Using XRD to test the phase structure of the particles, it was found that the diffraction peaks L corresponded one by one to the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of ordered structure. After calculation, the degree of order was 0.92. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity was 2478 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 14

[0089] A method for microwave-induced synthesis of highly ordered high-entropy nanoparticles in this example specifically includes the following steps: Measure ferrous chloride and palladium chloride as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Ni, Cu, Rh elements with an equimolar ratio. The molar ratio between the X, Y, and M metal raw materials is 0.8:0.8:0.32:0.32:0.32. Subsequently, weigh the reducing agent sodium bisulfite and the solvent triethanolamine oleate and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 2.4, and the solvent is 10 - 60 ml. Under the condition of high-purity nitrogen, mechanical stirring is carried out. The mechanical stirring speed is 500 rpm / min. It is heated to 110 °C at a heating rate of 1 °C / min, and kept warm for 45 min. Then it is heated to 260 °C at a heating rate of 7 °C / min and kept warm for 10 h, and then cooled to room temperature.

[0090] Add the centrifugate 1 acetone to the three-necked flask after the reaction, mix it evenly, and then use a centrifuge for centrifugation. The centrifugation speed is 12000 rpm / min, and the centrifugation time is 3 min. Pour off the upper layer liquid, add the centrifugate 1 acetone to the precipitate and mix it evenly. Repeat the above centrifugation operation 6 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 70 °C, and the drying time is 16 h to obtain a black powder.

[0091] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 90 wt.% of the black powder. Then transfer the mixture into a microwave oven, and introduce high-purity nitrogen at a flow rate of 200 μL / min. Subsequently, close the outlet and inlet valves, start the diffusion pump to evacuate the air, and evacuate the microwave oven to 5×10 -5 MPa. Then, with a microwave output power of 950 W, heat for 5 min, and then cool to room temperature.

[0092] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 cyclohexanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 30:1, the addition amount of ammonia water to the synthesized sample is 8:1, and the addition amount of cyclohexanol to the synthesized sample is 7:1. The units are all ml:mg. The three centrifugation parameters are the same. Among them, the centrifugation speed is 5000 rpm / min, and centrifuge for 10 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0093] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 2.00 nm. Use HADDF-MAPING to characterize the element distribution of the nanoparticles, and it is found that each element is distributed on the particles. Use XRD to test the phase structure of the particles, and it is found that the diffraction peaks correspond to L the characteristic peaks of the 10 ordered structures (PDF#43-1359) one by one, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.90. Finally, use VSM to test the magnetic properties of the nanoparticles, and its coercivity is 2000 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 15

[0094] A method for microwave-induced synthesis of high-entropy nanoparticles with an ordered structure in this example specifically includes the following steps: Measure cobalt acetylacetonate and platinum acetylacetonate as the X and Y metal raw materials respectively, and then measure the M metal raw materials. The M metal raw materials are composed of acetylacetonate salts of Mn, Zn, Cd, Ni, Cu, Ru, Rh, Ir, Pd, Ag, Au, Bi elements with an equimolar ratio. The molar ratio between the X, Y and M metal raw materials 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, weigh the reducing agent sodium nitrite and the solvent tetradecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.5, and the solvent is 10~60 ml. Under the condition of high-purity helium gas, carry out mechanical stirring at a mechanical stirring speed of 200 rpm / min, heat up to 115 °C at a heating rate of 5 °C / min, keep warm for 30 min, then heat up to 280 °C at a heating rate of 2 °C / min, keep warm for 8 h, and cool to room temperature.

[0095] Add 1-ethyl ether of the centrifugate to the three-necked flask after the reaction. Mix them evenly and then centrifuge using a centrifuge at a centrifugation speed of 1000 rpm / min for 10 min. Pour off the upper layer liquid. Add 1-ethyl ether of the centrifugate to the precipitate and mix evenly. Repeat the above centrifugation operation 3 times. Obtain the precipitate and conduct vacuum drying. The vacuum drying temperature is 80 °C and the drying time is 17 h to obtain a black powder.

[0096] Mix the black powder and the sintering aid lithium tetrafluoroborate evenly and place them in a crucible. The addition amount of the sintering aid is 25 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven and introduce high-purity helium gas at a flow rate of 100 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 5×10 -5 MPa. Then, with a microwave output power of 800 W, heat for 30 min, and then cool to room temperature.

[0097] Add the synthesized sample to deionized water, ammonia water, and 2-isopropyl alcohol of the centrifugate in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 20:1, the addition amount of ammonia water to the synthesized sample is 2:1, and the addition amount of 2-isopropyl alcohol to the synthesized sample is 1:1. The unit is ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 12000 rpm / min and the centrifugation time is 3 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0098] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 19.14 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks correspond one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.93. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 2672 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 16

[0099] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure cobalt chloride and chloroplatinic acid as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Mn, Zn, Ru, Ni, Cu, Sm, Pr, Yb, Eu, Sb, Au, Hg elements in an equimolar ratio. The molar ratio among the X, Y, and M metal raw materials 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, weigh the reducing agent sodium citrate and the solvent dioctadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 3.0, and the solvent is 10 - 60 ml. Under the condition of a hydrogen-argon mixed gas (5% H2), perform mechanical stirring at a mechanical stirring speed of 300 rpm / min. Heat to 105 °C at a heating rate of 8 °C / min, keep warm for 60 min, then heat to 360 °C at a heating rate of 5 °C / min, keep warm for 3 h, and cool to room temperature.

[0100] Add n-hexane of centrifugate 1 to the three-necked flask after the reaction, mix it evenly, and then centrifuge it using a centrifuge at a centrifugation speed of 8000 rpm / min for 8 min. Pour off the upper layer liquid, add n-hexane of centrifugate 1 to the precipitate and mix it evenly. Repeat the above centrifugation operation 4 times, and perform vacuum drying on the obtained precipitate. The vacuum drying temperature is 40 °C, and the drying time is 24 h to obtain a black powder.

[0101] Mix the black powder and the sintering aid boron oxide evenly and place them in a crucible. The addition amount of the sintering aid is 30 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, and introduce a hydrogen-argon mixed gas (5% H2) at a flow rate of 60 μL / min. Then close the air outlet and ventilation valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 6×10 -5 MPa, then heat at a microwave output power of 1000 W for 5 min, and then cool to room temperature.

[0102] Add the synthesized sample to deionized water, ammonia water, and centrifugate 2 in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 25:1, the addition amount of ammonia water to the synthesized sample is 5:1, and the addition amount of ethanol to the synthesized sample is 2:1. The units are all ml:mg. The three centrifugation parameters are the same, among which the centrifugation speed is 6000 rpm / min and the centrifugation time is 8 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0103] The TEM observation of the nanoparticles reveals that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 16.67 nm. The HADDF-MAPING is used to characterize the elemental distribution of the nanoparticles, and it is found that each element is distributed on the particles. The XRD is used to test the phase structure of the particles, and it is found that the diffraction peaks correspond one by one to the characteristic peaks of the L 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.92. Finally, the VSM is used to test the magnetic properties of the nanoparticles, and its coercivity is 6371 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 17

[0104] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure acetylacetone gold and acetylacetone copper as X and Y metal raw materials respectively, and then measure the M metal raw materials. The M metal raw materials are composed of acetylacetonate salts of Mn, Zn, Co, Ni, Rh, Ru, Tl, Te, Th, Hg, Pb, Bi elements in equimolar ratio. The molar ratio between X, Y and M metal raw materials 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, weigh the reducing agent sodium bisulfite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 1.2, and the solvent is 10 - 60 ml. Under the condition of high-purity argon, mechanical stirring is carried out, and the mechanical stirring speed is 200 rpm / min. The temperature is raised to 110 °C at a heating rate of 5 °C / min, and kept warm for 60 min. Then, the temperature is raised to 360 °C at a heating rate of 3 °C / min and kept warm for 3 h, and then cooled to room temperature.

[0105] Add chloroform of centrifugate 1 to the three-necked flask after the reaction, mix it evenly and then centrifuge it using a centrifuge. The centrifugation speed is 6000 rpm / min and the centrifugation time is 6 min. Pour off the upper layer liquid, add chloroform of centrifugate 1 to the precipitate and mix it evenly. Repeat the above centrifugation operation 5 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 55 °C and the drying time is 18 h to obtain a black powder.

[0106] Mix the black powder and the sintering aid calcium hydride evenly and place them in a crucible. The addition amount of the sintering aid is 1 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, and introduce high-purity argon at a flow rate of 600 μL / min. Then, close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 1×10 -4 MPa, and then heat it at a microwave output power of 750 W for 30 min, and then cool it to room temperature.

[0107] The synthesized sample was successively added with deionized water, ammonia water, and centrifugate 2 ethanol, mixed evenly and then centrifuged. The addition amount of deionized water to the synthesized sample was 15:1, the addition amount of ammonia water to the synthesized sample was 8:1, and the addition amount of ethanol to the synthesized sample was 6:1, with the unit being ml:mg. The centrifugation parameters were the same for 3 times, with a centrifugation speed of 4000 rpm / min and centrifugation for 10 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0108] Using TEM to observe the nanoparticles, it was found that the particle morphology and size were relatively uniform; the average particle size of the nanoparticles was 17.91 nm. HADDF-MAPING was used to characterize the element distribution of the nanoparticles, and it was found that each element was distributed on the particles. XRD was used to test the phase structure of the particles, and it was found that the diffraction peaks corresponded one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles had a relatively high ordered structure. After calculation, the degree of order was 0.85. Finally, VSM was used to test the magnetic properties of the nanoparticles, and its coercivity was 3267 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 18

[0109] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure gold chloride and copper chloride as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Co, Ni, Zn, Ru, Rh, and Ir with an equimolar ratio. The molar ratio between the X, Y, and M metal raw materials is 0.4:0.4:0.16:0.16:0.16:0.16:0.16:0.16. Subsequently, weigh the reducing agent sodium nitrite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 3.6, and the solvent is 10 - 60 ml. Under the condition of high-purity nitrogen, mechanical stirring is carried out at a mechanical stirring speed of 300 rpm / min. The temperature is raised to 115 °C at a heating rate of 8 °C / min and kept warm for 90 min, then the temperature is raised to 340 °C at a heating rate of 5 °C / min and kept warm for 3 h, and then cooled to room temperature.

[0110] Add centrifugate 1 ether to the three-necked flask after the reaction, mix it evenly and then use a centrifuge for centrifugation at a centrifugation speed of 5000 rpm / min for 5 min. Pour off the upper layer liquid, add centrifugate 1 ether to the precipitate and mix it evenly. Repeat the above centrifugation operation 6 times, and vacuum-dry the obtained precipitate. The vacuum drying temperature is 75 °C and the drying time is 24 h to obtain a black powder.

[0111] Mix the black powder and the sintering aid calcium oxide evenly and place them in a crucible. The addition amount of the sintering aid is 1.2 wt.% of the black powder. Then transfer the mixture into a microwave oven, and introduce high-purity nitrogen at a flow rate of 100 μL / min. Subsequently, close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 2×10 -4 MPa. Then, with a microwave output power of 1000 W, heat for 10 min, and then cool to room temperature.

[0112] Add the synthesized sample to deionized water, ammonia water, and centrifuged liquid 2-propanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 11:1, the addition amount of ammonia water to the synthesized sample is 6:1, and the addition amount of 2-propanol to the synthesized sample is 10:1. The units are all ml:mg. The three centrifugation parameters are the same, where the centrifugation speed is 5000 rpm / min and the centrifugation time is 5 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0113] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 20.00 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks correspond to L the characteristic peaks of the 10 ordered structures (PDF#43-1359) one by one, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.88. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 3517 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 19

[0114] A method for microwave-induced synthesis of high-entropy nanoparticles with an ordered structure in this example specifically includes the following steps: Measure chloroauric acid and copper chloride as the X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Co, Ni, Zn, Ru, Rh, Pd elements with an equimolar ratio. The molar ratio between the X, Y and M metal raw materials is 0.7:0.7:0.28:0.28:0.28:0.28:0.28:0.28. Subsequently, weigh the reducing agent sodium citrate and the solvent oleylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 2.4, and the solvent is 10 - 60 ml. Under the condition of high-purity helium gas, carry out mechanical stirring at a mechanical stirring speed of 100 rpm / min, heat up to 105 °C at a heating rate of 10 °C / min, keep warm for 30 min, then heat up to 320 °C at a heating rate of 4 °C / min, keep warm for 3 h, and then cool to room temperature.

[0115] Add n-hexane of centrifugate 1 to the three-necked flask after the reaction. Mix them evenly and then centrifuge using a centrifuge at a centrifugation speed of 8000 rpm / min for 5 min. Pour off the upper layer liquid. Add n-hexane of centrifugate 1 to the precipitate and mix evenly. Repeat the above centrifugation operation 3 times. Perform vacuum drying on the obtained precipitate, where the vacuum drying temperature is 60 °C and the drying time is 24 h to obtain a black powder.

[0116] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 50 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, and introduce high-purity argon at a flow rate of 150 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 5×10 -5 MPa. Then, with a microwave output power of 700 W, heat for 20 min, and then cool to room temperature.

[0117] Add the synthesized sample to deionized water, ammonia water, and cyclohexanol of centrifugate 2 in sequence and mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 20:1, the addition amount of ammonia water to the synthesized sample is 7:1, and the addition amount of cyclohexanol to the synthesized sample is 5:1. The unit is ml:mg. The three centrifugation parameters are the same. Among them, the centrifugation speed is 7000 rpm / min and the centrifugation time is 10 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0118] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 18.54 nm. Use HADDF-MAPING to characterize the element distribution of the nanoparticles, and it is found that each element is distributed on the particles. Use XRD to test the phase structure of the particles, and it is found that the diffraction peaks correspond one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.90. Finally, use VSM to test the magnetic properties of the nanoparticles, and its coercivity is 3478 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 20

[0119] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material is composed of acetylacetonates of Co, Cu, Ru, Rh, Ir, Ag, Au elements with an equimolar ratio. The molar ratio among the X, Y, and M metal raw materials is 0.8:0.8:0.32:0.32:0.32:0.32:0.32:0.32:0.32. Subsequently, weigh the reducing agent glucose and the solvent oleylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 1.5, and the solvent is 10 - 60 ml. Under the condition of a hydrogen-argon mixture (5% H2), perform mechanical stirring at a mechanical stirring speed of 600 rpm / min. Heat to 100 °C at a heating rate of 3 °C / min, keep warm for 45 min, then heat to 300 °C at a heating rate of 10 °C / min, keep warm for 8 h, and cool to room temperature.

[0120] Add n-hexane of centrifugate 1 to the three-necked flask after the reaction, mix them evenly, and then use a centrifuge for centrifugation at a centrifugation speed of 6000 rpm / min for 9 min. Pour off the upper layer liquid, add n-hexane of centrifugate 1 to the precipitate and mix evenly. Repeat the above centrifugation operation 6 times, obtain the precipitate and perform vacuum drying. The vacuum drying temperature is 40 °C, and the drying time is 24 h to obtain a black powder.

[0121] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 80 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, introduce high-purity nitrogen at a flow rate of 180 μL / min, then close the air outlet and air inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 3×10 -5 MPa, then heat at a microwave output power of 750 W for 30 min, and then cool to room temperature.

[0122] Add the synthesized sample to deionized water, ammonia water, and isopropyl alcohol of centrifugate 2 in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 8:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of isopropyl alcohol to the synthesized sample is 3:1. The unit is ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 6000 rpm / min, and the centrifugation time is 5 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0123] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 18.16 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks are consistent with LThe characteristic peaks of the ordered structure (PDF#43-1359) correspond one by one, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.95. Finally, the magnetic properties of the nanoparticles were tested by VSM, and its coercivity is 7428 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 21

[0124] In this example, a method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material is composed of acetylacetonate salts of Mn, Co, Ni, Rh, Ir, Pd, Hg, Pb, Bi elements with an equimolar ratio. The molar ratio between the X, Y and M metal raw materials is 0.3:0.3:0.12:0.12:0.12:0.12:0.12:0.12:0.12:0.12. Subsequently, weigh the reducing agent ascorbic acid and the solvent triethanolamine oleate and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 1.6, and the solvent is 10-60 ml. Mechanical stirring is carried out under high-purity argon conditions, and the mechanical stirring speed is 400 rpm / min. The temperature is raised to 120 °C at a heating rate of 2 °C / min and held for 60 min, then the temperature is raised to 320 °C at a heating rate of 8 °C / min and held for 1 h, and then cooled to room temperature.

[0125] Add centrifugate 1 n-hexane to the three-necked flask after the reaction, mix them evenly and then centrifuge using a centrifuge. The centrifugation speed is 10,000 rpm / min and the centrifugation time is 4 min. Pour off the upper layer liquid, add centrifugate 1 n-hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 4 times, and vacuum dry the obtained precipitate. The vacuum drying temperature is 80 °C and the drying time is 12 h to obtain a black powder.

[0126] Mix the black powder and the sintering aid potassium carbonate evenly and place them in a crucible. The addition amount of the sintering aid is 10 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, and introduce high-purity helium gas at a flow rate of 80 μL / min. Then close the air outlet and ventilation valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 5×10 -5 MPa, then heat at a microwave output power of 800 W for 20 min, and then cool to room temperature.

[0127] The synthesized sample was successively added with deionized water, ammonia water, and centrifugate 2 ethanol, mixed evenly, and then centrifuged. The addition amount of deionized water to the synthesized sample was 10:1, the addition amount of ammonia water to the synthesized sample was 6:1, and the addition amount of ethanol to the synthesized sample was 3:1. The units were all ml:mg. The three centrifugation parameters were the same. Among them, the centrifugation speed was 6000 rpm / min, and the centrifugation time was 8 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0128] Using TEM to observe the nanoparticles, it was found that the particle morphology and size uniformity were good; the average particle size of the nanoparticles was 13.49 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it was found that each element was distributed on the particles. Using XRD to test the phase structure of the particles, it was found that the diffraction peaks corresponded one by one to L the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of ordered structure. After calculation, the degree of order was 0.93. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity was 5417 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 22

[0129] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure ferric chloride and potassium tetrachloroplatinate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Mn, Co, Ni, Rh, Ir, Pd, Hg, Pb, Bi elements with an equimolar ratio. The molar ratio between X, Y, and M metal raw materials is 0.1:0.1:0.04:0.04:0.04:0.04:0.04:0.04:0.04:0.04:0.04. Subsequently, weigh the reducing agent sodium bisulfite and the solvent triethanolamine oleate and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 2.4, and the solvent is 10 - 60 ml. Under the condition of high-purity nitrogen, mechanical stirring is carried out. The mechanical stirring speed is 500 rpm / min. The temperature is raised to 110 °C at a heating rate of 1 °C / min and kept warm for 45 min, and then the temperature is raised to 260 °C at a heating rate of 7 °C / min and kept warm for 10 h, and then cooled to room temperature.

[0130] Add centrifugate 1 chloroform to the reaction three-necked flask after the reaction, mix it evenly, and then use a centrifuge for centrifugation. The centrifugation speed is 4000 rpm / min, and the centrifugation time is 8 min. Pour off the upper layer liquid, add centrifugate 1 chloroform to the precipitate and mix it evenly. Repeat the above centrifugation operation 5 times, and vacuum-dry the obtained precipitate. The vacuum-drying temperature is 50 °C, and the drying time is 15 h to obtain a black powder.

[0131] Mix the black powder and the sintering aid boron oxide evenly and place them in a crucible. The addition amount of the sintering aid is 40 wt.% of the black powder. Then transfer the mixture into a microwave oven, and introduce a hydrogen-argon mixture (5% H2) at a flow rate of 100 μL / min. Subsequently, close the outlet and inlet valves, start the diffusion pump to evacuate the vacuum, and evacuate the vacuum in the microwave oven to 3×10 -5 MPa. Then, with a microwave output power of 850 W, heat for 15 min, and then cool to room temperature.

[0132] Add the synthesized sample to deionized water, ammonia water, and centrifuged liquid 2 ethanol in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 50:1, the addition amount of ammonia water to the synthesized sample is 10:1, and the addition amount of ethanol to the synthesized sample is 10:1. The units are all ml:mg. The three centrifugation parameters are the same. Among them, the centrifugation speed is 12,000 rpm / min, and centrifuge for 10 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0133] Using TEM to observe the nanoparticles, it is found that the particle morphology and size are relatively uniform; the average particle size of the nanoparticles is 13.73 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks correspond to L the characteristic peaks of the 10 ordered structures (PDF#43-1359) one by one, indicating that the synthesized nanoparticles have a relatively high ordered structure. After calculation, the degree of order is 0.92. Finally, using VSM to test the magnetic properties of the nanoparticles, its coercivity is 5371 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size. Example 23

[0134] A method for microwave-induced synthesis of high-entropy nanoparticles with an ordered structure in this example specifically includes the following steps: Measure ferric chloride and potassium hexachloroplatinate as X and Y metal raw materials respectively, and then measure the M metal raw material. The M metal raw material consists of chlorides of Zn, Co, Ni, Cu, Ru, Rh, Ir, Ce, Sm, Ag elements with an equimolar ratio. The molar ratio between X, Y, and M metal raw materials 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, weigh the reducing agent sodium nitrite and the solvent tetradecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 2.5, and the solvent is 10 - 60 ml. Under the condition of high-purity helium gas, carry out mechanical stirring at a mechanical stirring speed of 200 rpm / min, heat to 115 °C at a heating rate of 5 °C / min, keep warm for 30 min, then heat to 280 °C at a heating rate of 2 °C / min, keep warm for 8 h, and then cool to room temperature.

[0135] Add centrifugation liquid 1 acetone to the three-necked flask after the reaction. Mix them evenly and then centrifuge using a centrifuge at a centrifugation speed of 12,000 rpm / min for 3 min. Pour off the upper layer liquid. Add centrifugation liquid 1 acetone to the precipitate and mix evenly. Repeat the above centrifugation operation 6 times. Obtain the precipitate and perform vacuum drying. The vacuum drying temperature is 70 °C and the drying time is 16 h to obtain a black powder.

[0136] Mix the black powder and the sintering aid calcium hydride evenly and place them in a crucible. The addition amount of the sintering aid is 1.2 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven and introduce high-purity argon at a flow rate of 60 μL / min. Then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 2×10 -4 MPa. Then, with a microwave output power of 750 W, heat for 60 min, and then cool to room temperature.

[0137] Add the synthesized sample to deionized water, ammonia water, and centrifugation liquid 2 propanol in sequence. Mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 20:1, the addition amount of ammonia water to the synthesized sample is 5:1, and the addition amount of propanol to the synthesized sample is 5:1. The units are all ml:mg. The three centrifugation parameters are the same. The centrifugation speed is 8,000 rpm / min and the centrifugation time is 5 min. Finally, the obtained black powder is highly ordered high-entropy nanoparticles with an ordered structure.

[0138] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 15.15 nm. Use HADDF-MAPING to characterize the element distribution of the nanoparticles, and it is found that each element is distributed on the particles. Use XRD to test the phase structure of the particles, and it is found that the diffraction peaks correspond one by one to L the characteristic peaks of the 10 ordered structure (PDF#43-1359), indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.95. Finally, use VSM to test the magnetic properties of the nanoparticles, and its coercivity is 3258 Oe. The above results confirm the synthesis of high-entropy nanoparticles with a high degree of order, high coercivity, and small size. Example 24

[0139] A method for microwave-induced synthesis of ordered-structured high-entropy nanoparticles in this embodiment specifically includes the following steps: Measure ferric chloride and ammonium tetrachloroplatinate as X and Y metal raw materials respectively, and then measure M metal raw materials. The M metal raw materials are composed of chlorides of Co, Ni, Cu elements with an equimolar ratio. The molar ratio between X, Y and M metal raw materials is 0.5:0.5:0.20:0.20:0.20. Subsequently, weigh the reducing agent sodium citrate and the solvent dioctadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw materials is 3.0, and the solvent is 10 - 60 ml. Under the condition of a hydrogen-argon mixed gas (5% H2), perform mechanical stirring at a mechanical stirring speed of 300 rpm / min, heat to 105 °C at a heating rate of 8 °C / min, keep warm for 60 min, then heat to 360 °C at a heating rate of 5 °C / min, keep warm for 3 h, and cool to room temperature.

[0140] Add 1 ether of the centrifugate to the three-necked flask after the reaction, mix it evenly, and then use a centrifuge for centrifugation. The centrifugation speed is 1000 rpm / min, and centrifuge for 10 min. Pour off the upper layer liquid, add 1 ether of the centrifugate to the precipitate and mix evenly. Repeat the above centrifugation operation 3 times, obtain the precipitate and perform vacuum drying. The vacuum drying temperature is 80 °C, and the drying time is 17 h to obtain black powder.

[0141] Mix the black powder and the sintering aid calcium oxide evenly and place them in a crucible. The addition amount of the sintering aid is 1.4 wt.% of the black powder. Subsequently, transfer the mixture into a microwave oven, introduce high-purity nitrogen at a flow rate of 90 μL / min, then close the outlet and inlet valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 1×10 -4 MPa, then heat at a microwave output power of 850 W for 20 min, and then cool to room temperature.

[0142] Add the synthesized sample to deionized water, ammonia water, and 2 cyclohexanol of the centrifugate in sequence, mix them evenly and then centrifuge. The addition amount of deionized water to the synthesized sample is 20:1, the addition amount of ammonia water to the synthesized sample is 8:1, and the addition amount of cyclohexanol to the synthesized sample is 10:1. The unit is ml:mg. The centrifugation parameters for all 3 times are the same. The centrifugation speed is 6000 rpm / min, and centrifuge for 10 min. Finally, the obtained black powder is ordered-structured high-entropy nanoparticles.

[0143] Using TEM to observe the nanoparticles, it is found that the particle morphology and size uniformity are good; the average particle size of the nanoparticles is 13.51 nm. Using HADDF-MAPING to characterize the element distribution of the nanoparticles, it is found that each element is distributed on the particles. Using XRD to test the phase structure of the particles, it is found that the diffraction peaks are consistent with LThe characteristic peaks of the ordered structure (PDF#43-1359) are in one-to-one correspondence, indicating that the synthesized nanoparticles have a high degree of ordered structure. After calculation, the degree of order is 0.93. Finally, the magnetic properties of the nanoparticles were tested by VSM, and its coercivity was 2478 Oe. The above results confirm the synthesis of high-entropy nanoparticles with high degree of order, high coercivity and small size. Example 25

[0144] A method for microwave-induced synthesis of ordered structure high-entropy nanoparticles in this example specifically includes the following steps: Measure iron acetylacetonate and platinum acetylacetonate; respectively as X and Y metal raw materials, then measure the M metal raw material. The M metal raw material is composed of acetylacetonate salts of Mn, Zn, Co, Ni, Cu, Sm, Pr, Yb, Eu, Sb, Au, Hg elements in equimolar ratio. The molar ratio between X, Y and M metal raw materials 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, weigh the reducing agent sodium bisulfite and the solvent hexadecylamine and add them to a three-necked flask. The molar ratio of the reducing agent to the metal raw material is 1.2, and the solvent is 10-60 ml. Mechanical stirring is carried out under high-purity argon conditions, and the mechanical stirring speed is 200 rpm / min. It is heated to 110 °C at a heating rate of 5 °C / min and kept warm for 60 min, then heated to 360 °C at a heating rate of 3 °C / min and kept warm for 3 h, and then cooled to room temperature.

[0145] Add centrifugate 1 n-hexane to the three-necked flask after the reaction, mix them evenly and then use a centrifuge for centrifugation. The centrifugation speed is 8000 rpm / min and the centrifugation time is 8 min. Pour off the upper layer liquid, add centrifugate 1 n-hexane to the precipitate and mix evenly. Repeat the above centrifugation operation 4 times, and vacuum dry the obtained precipitate. The vacuum drying temperature is 40 °C and the drying time is 24 h to obtain black powder.

[0146] Mix the black powder and the sintering aid sodium chloride evenly and place them in a crucible. The addition amount of the sintering aid is 100 wt.% of the black powder. Subsequently, transfer the mixture to a microwave oven, introduce high-purity nitrogen at a flow rate of 100 μL / min, then close the air outlet and ventilation valves, start the diffusion pump to pump vacuum, and pump the vacuum in the microwave oven to 3×10 -5 MPa, then heat at a microwave output power of 700 W for 60 min, and then cool to room temperature.

[0147] The synthesized sample was successively added with deionized water, ammonia water, and centrifuged solution 2 ethanol, mixed evenly and then centrifuged. The addition amount of deionized water to the synthesized sample was 20:1, the addition amount of ammonia water to the synthesized sample was 5:1, and the addition amount of ethanol to the synthesized sample was 5:1. The unit was ml:mg. The centrifugation parameters were the same for 3 times. Among them, the centrifugation speed was 12,000 rpm / min and the centrifugation time was 5 min. Finally, a black powder of highly ordered high-entropy nanoparticles was obtained.

[0148] Using TEM to observe the nanoparticles, it was found that the particle morphology and size had good uniformity; the average particle size of the nanoparticles was 15.62 nm. HADDF-MAPING was used to characterize the element distribution of the nanoparticles, and it was found that each element was distributed on the particles. XRD was used to test the phase structure of the particles, and it was found that the diffraction peaks corresponded to L the characteristic peaks of the 10 ordered structures (PDF#43-1359), indicating that the synthesized nanoparticles had a high degree of ordered structure. After calculation, the degree of order was 0.92. Finally, VSM was used to test the magnetic properties of the nanoparticles, and its coercivity was 4231 Oe. The above results confirmed the synthesis of high-entropy nanoparticles with high degree of order, high coercivity, and small size.

[0149] It can be seen from the above examples that the high-entropy nanoparticles synthesized by microwave induction of the present invention exhibit excellent ordered structure, high coercivity, and small particle size, and the element distribution of the nanoparticles is uniform and the morphology and size have good uniformity.

Claims

1. A method for synthesizing ordered high-entropy nanoparticles by microwave induction, characterized in that: The following steps are involved: (1) Add metal raw materials X, Y and M, reducing agent and solvent into a reaction vessel, stir mechanically and heat under protective gas conditions, heat to 100-120°C at a heating rate of 1-10°C / min and keep warm for 30-90 min, then heat to 260-360°C at a heating rate of 1-10°C / min and keep warm for 1-10 h, and cool to room temperature; (2) Add centrifuge 1 to the product of step (1), mix and centrifuge, discard the upper layer, add centrifuge 1 to the precipitate again, mix and repeat the centrifugation operation 3 to 6 times, obtain the precipitate and vacuum dry it to obtain a black powder; (3) The black powder obtained in step (2) and the sintering aid are mixed evenly and placed in a crucible, which is then transferred to a microwave oven, into which a protective gas is introduced, and the vacuum in the microwave oven is evacuated to 3×10 -4 ~3×10 -5 MPa, then heated at 600W~1000W microwave output power for 1~100min, and cooled to room temperature; (4) adding deionized water, ammonia water, and centrifuge solution 2 to the product synthesized in step (3) in sequence, mixing the mixture and centrifuging the mixture to obtain high-entropy nanoparticles with an ordered structure; The raw materials X and Y are selected from a combination of two of Fe, Pt, Pd, Co, Au, and Cu, and the raw material M is selected from 3 to 12 of the elements 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, and the molar ratio of X, Y, and M is X:Y:M1:M2:…:M n It is (0.1~1.0):(0.1~1.0):(0.04~0.4):(0.04~0.4):…:(0.04~0.4), 3≤n≤12.

2. The method for synthesizing ordered high-entropy nanoparticles by microwave induction 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 acetylacetonate, ferric chloride, and ferrous chloride; the Pt metal raw material is one of platinum acetylacetonate, potassium tetrachloroplatinate, potassium hexachloroplatinate, ammonium tetrachloroplatinate, and chloroplatinic acid; the Pd metal raw material is one of palladium chloride, palladium acetylacetonate, and palladium hexafluoroacetylacetonate; the Co metal raw material is one of cobalt acetylacetonate and cobalt chloride; the Au metal raw material is one of gold acetylacetonate, gold chloride, and tetrachloroauric acid; the Cu metal raw material is one of copper acetylacetonate and copper chloride; the metal raw material M is one of acetylacetonate and chloride.

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

6.

4. The method for synthesizing ordered high-entropy nanoparticles by microwave induction according to claim 1, characterized in that: The mechanical stirring speed in step (1) is 100-600 rpm / min.

5. The method for synthesizing ordered high-entropy nanoparticles by microwave induction according to claim 1, characterized in that: In step (2), the vacuum drying temperature is 40-80°C, the time is 6-24h, the centrifugal liquid 1 is one of n-hexane, chloroform, acetone, and ether, the centrifugal speed is 1000-120000rpm / min, and the centrifugation is 3-10min; in step (4), the centrifugal liquid 2 is one of ethanol, isopropanol, propanol, and cyclohexanol, the centrifugal speed is 1000-12000rpm / min, and the centrifugation is 3-10min; the ratio of the amount of deionized water, ammonia water, and centrifugal liquid 2 added to the amount of the synthetic product added is 1-50:1, 1-10:1, and 1-10:1, respectively, in units of ml:mg.

6. The method for synthesizing ordered high-entropy nanoparticles by microwave induction according to claim 1, characterized in that: The shielding gas is one of high-purity argon, high-purity nitrogen, high-purity helium, and hydrogen-argon mixed gas. The flow rate is 60~600μL / min, and the H2 content in the hydrogen-argon mixed gas is 5%.

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

8. The method for synthesizing ordered high-entropy nanoparticles by microwave induction according to claim 1, characterized in that: The high entropy nanoparticles contain 5 to 14 main element metals, have an average particle size of 2.0 to 20.0 nm, a degree of order of 7.0 to 9.5, and a coercive force of 2000 to 8000 Oe.

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

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

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