A device, preparation method and application for flash evaporation preparation of high-entropy metal nanoparticles

Abstract

The embodiment of the present invention relates to the technical field of nanomaterial preparation, and specifically discloses a high-entropy metal nanoparticle flash evaporation preparation device, a preparation method and an application. The high-entropy metal nanoparticle flash evaporation preparation device includes a pulsed power supply box, an insulated high-temperature reaction tube, a first high-voltage electrode and a second high-voltage electrode. The pulsed power supply box is connected to both ends of the insulated high-temperature reaction tube through the first high-voltage electrode and the second high-voltage electrode respectively. By using this electrode pair to perform high-voltage discharge on the raw materials placed in the insulated high-temperature reaction tube, the present invention effectively converts amorphous metal into high-entropy metal nanoparticles, with low production cost and fast production speed, suitable for industrial large-scale production, solving the problem that the existing traditional preparation technology of high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale. Moreover, the high-entropy metal nanoparticle preparation method provided by the embodiment of the present invention has simple steps and low cost, and has broad market prospects.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of nanomaterial preparation, and specifically, to a flash evaporation preparation device, a preparation method and an application of high-entropy metal nanoparticles. Background Art

[0002] With the continuous development of science and technology, more and more new materials have been developed and widely used in various fields. Among them, high-entropy metal nanoparticles, as a material composed of a uniform mixture of multiple metal elements, are formed by alloying multiple metal elements into a single nanoscale product, and their material properties are expected to exceed those of single-element (or single) nanoparticles. Generally, high-entropy metal nanoparticles have wide application values in aspects including catalysis, energy storage, and biological / plasma imaging due to their adjustable activity, excellent thermal stability and chemical stability, and synergistic catalytic effect.

[0003] Currently, the main method for preparing high-entropy metal nanoparticles comes from wet chemical synthesis, and different particle sizes, shapes and phases can usually be obtained. However, most of the alloy components prepared by the existing wet chemical methods do not exceed three elements. In addition, melt processing is a scalable method that can produce high-entropy alloys composed of five or more elements, showing great potential as structural materials. However, due to conditional limitations, only a limited family of high-entropy alloys has been realized so far, and the application scope is limited and large-scale production cannot be achieved.

[0004] Therefore, the above existing technical solutions have the following deficiencies in actual use: The traditional preparation technology of existing high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide a flash evaporation preparation device for high-entropy metal nanoparticles to solve the problem that the traditional preparation technology of existing high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale as proposed in the above background art.

[0006] To achieve the above purpose, the embodiments of the present invention provide the following technical solutions:

[0007] A flash evaporation preparation device for high-entropy metal nanoparticles, including a pulsed power supply box, and the flash evaporation preparation device for high-entropy metal nanoparticles further includes:

[0008] An insulated high-temperature reaction tube for placing mixed conductive powder to be subjected to high-voltage discharge; wherein, the mixed conductive powder includes conductive carbon black with reducibility and metal powder;

[0009] The first high-voltage electrode and the second high-voltage electrode are respectively connected to the two ends of the insulated high-temperature reaction tube through the first high-voltage electrode and the second high-voltage electrode to discharge the mixed conductive powder with high voltage to generate high-entropy metal nanoparticles.

[0010] As a further solution of an embodiment of the present invention: the high-entropy metal nanoparticle flash evaporation preparation device also includes a first copper plug and a second copper plug, and the second copper plug and the first copper plug are respectively inserted into the left and right ends of the insulated high-temperature reaction tube filled with mixed conductive powder.

[0011] As a further solution of the embodiment of the present invention: the first high-voltage electrode is clamped at the outer end opening of the first copper plug, and the second high-voltage electrode is clamped at the outer end opening of the second copper plug.

[0012] As a further solution of an embodiment of the present invention: the electric pulse characteristics of the pulse power supply box are specifically as follows: the time required for the pulse current to rise from 0A to the set value is less than 10ms, the pulse width is 20-500ms, and the pulse current setting value is 0-500A.

[0013] Another object of the present invention is to provide a method for preparing high-entropy metal nanoparticles, the method comprising the following steps:

[0014] 1) fully mixing the reducible conductive carbon black and the metal powder in proportion to obtain a mixed conductive powder;

[0015] 2) Weighing the mixed conductive powder and introducing it into a clean insulated high-temperature reaction tube, and connecting the pulse power supply box to both ends of the insulated high-temperature reaction tube through the first high-voltage electrode and the second high-voltage electrode respectively;

[0016] 3) Setting the discharge parameters of the pulse power supply box to discharge the mixed conductive powder at high voltage to generate high entropy metal nanoparticles.

[0017] Another object of the embodiments of the present invention is to provide an application of the above-mentioned method for preparing high-entropy metal nanoparticles in nanomaterial processing.

[0018] Compared with the prior art, the embodiments of the present invention have the following beneficial effects:

[0019] The high-entropy metal nanoparticle flash evaporation preparation device provided by the embodiment of the present invention includes a pulsed power supply box, an insulated high-temperature reaction tube, a first high-voltage electrode, and a second high-voltage electrode. The pulsed power supply box is respectively connected to both ends of the insulated high-temperature reaction tube through the first high-voltage electrode and the second high-voltage electrode to discharge and generate high-entropy metal nanoparticles by high-voltage discharge of the mixed conductive powder. By setting up a pulsed power supply box, an insulated high-temperature reaction tube, and two electrodes connected to the pulsed power supply box, and using these electrodes to perform high-voltage discharge on the raw material (i.e., the mixed conductive powder) placed in the insulated high-temperature reaction tube, the amorphous metal is effectively converted into high-entropy metal nanoparticles, providing a new process method for large-scale production of high-entropy metals, solving the problem that the existing traditional preparation technology of high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale, and having a broad market prospect. The whole process of the high-entropy metal nanoparticle preparation method provided by the embodiment of the present invention only consumes electricity, has low production costs, fast production speed, is suitable for industrial large-scale production, meets the actual production requirements, and has great application value. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of the high-entropy metal nanoparticle flash evaporation preparation device provided by an embodiment of the present invention.

[0021] Figure 2 It is a TEM image of the sample prepared under a pulsed current of 100 A in the high-entropy metal nanoparticle preparation method provided by an embodiment of the present invention.

[0022] Figure 3 It is a TEM image of the sample prepared under a pulsed current of 120 A in the high-entropy metal nanoparticle preparation method provided by an embodiment of the present invention.

[0023] Figure 4 It is a TEM image of the sample prepared under a pulsed current of 150 A in the high-entropy metal nanoparticle preparation method provided by an embodiment of the present invention.

[0024] In the figure: 1 - pulsed power supply box; 2 - first high-voltage electrode; 3 - first copper plug; 4 - mixed conductive powder; 5 - insulated high-temperature reaction tube; 6 - second copper plug; 7 - second high-voltage electrode; 8 - positive electrode interface; 9 - negative electrode interface. Detailed Embodiments

[0025] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clear and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments will help those skilled in the art to further understand the embodiments of the present invention, but do not limit the embodiments of the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the embodiments of the present invention, several modifications and improvements can still be made. These all belong to the protection scope of the embodiments of the present invention. In order to make the technical solutions of the embodiments of the present invention clearer, the well-known process steps and device structures in the art are omitted here.

[0026] In the description of the present invention, it should be understood that unless otherwise clearly defined and limited, the first feature being "above" or "below" or "in front of" or "behind" or "left" or "right" of the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through other features therebetween. Moreover, the first feature being "above" and "on the top" of the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below" and "under the bottom" of the second feature includes the first feature being directly below and obliquely below the second feature, or merely indicating that the first feature has a lower horizontal height than the second feature. The above-mentioned indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the embodiments of the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0027] To achieve the above object, the embodiments of the present invention provide the following technical solutions:

[0028] As Figure 1 shown, a high-entropy metal nanoparticle flash evaporation preparation device provided by an embodiment of the present invention, the high-entropy metal nanoparticle flash evaporation preparation device is specifically a device for preparing high-entropy metal nanoparticles using flash evaporation technology, the device includes a pulsed power supply box 1, and the high-entropy metal nanoparticle flash evaporation preparation device further includes:

[0029] An insulating high-temperature reaction tube 5 for placing a mixed conductive powder 4 to be subjected to high-voltage discharge; wherein, the mixed conductive powder 4 includes conductive carbon black with reducibility and metal powder;

[0030] A first high-voltage electrode 2 and a second high-voltage electrode 7. The pulsed power supply box 1 is respectively connected to both ends of the insulated high-temperature reaction tube 5 through the first high-voltage electrode 2 and the second high-voltage electrode 7 to discharge and generate high-entropy metal nanoparticles by high-voltage discharge of the mixed conductive powder 4.

[0031] Among them, the discharge is to rapidly increase the current to perform high-voltage discharge on the mixed conductive powder 4, so that the mixed conductive powder 4 reaches a temperature above 3000K within less than 100 ms, effectively converting the amorphous metal into high-entropy metal nanoparticles.

[0032] In the embodiment of the present invention, through the high-entropy metal nanoparticle flash evaporation preparation device, high-entropy metal nanoparticles can be prepared using the flash evaporation technology. By setting the pulsed power supply box 1, the insulated high-temperature reaction tube 5, and two electrodes connected to the pulsed power supply box 1 (i.e., the first high-voltage electrode 2 and the second high-voltage electrode 7), and using these electrodes to perform high-voltage discharge on the raw material (i.e., the mixed conductive powder 4) placed in the insulated high-temperature reaction tube 5, the high-voltage discharge of the capacitor bank of the pulsed power supply box 1 causes the mixed conductive powder 4 to reach a temperature above 3000K within less than 100 ms, effectively converting the amorphous metal into high-entropy metal nanoparticles. The whole process only needs to consume electricity, has low production cost, fast production speed, can achieve high-efficiency production, provides a new process method for large-scale production of high-entropy metals, and solves the problem that the existing traditional preparation technology of high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale.

[0033] As another preferred embodiment of the embodiment of the present invention, the high-entropy metal nanoparticle flash evaporation preparation device further includes a first copper plug 3 and a second copper plug 6. The second copper plug 6 and the first copper plug 3 are respectively inserted at the left and right ends of the insulated high-temperature reaction tube 5 filled with the mixed conductive powder 4 to achieve effective sealing of the insulated high-temperature reaction tube 5.

[0034] As another preferred embodiment of the embodiment of the present invention, the first high-voltage electrode 2 is clamped at the outer opening of the first copper plug 3, and the second high-voltage electrode 7 is clamped at the outer opening of the second copper plug 6. By setting the first copper plug 3 and the second copper plug 6, while realizing the electrical connection between the first high-voltage electrode 2 and the second high-voltage electrode 7 and the pulsed power supply box 1, the sealing effect during high-voltage discharge can be ensured.

[0035] As another preferred embodiment of the present invention, a positive electrode interface 8 and a negative electrode interface 9 are respectively provided on the outside of the pulse power supply box 1, the first high-voltage electrode 2 is connected to the negative electrode interface 9 through a wire, and the second high-voltage electrode 7 is connected to the positive electrode interface 8 through a wire, so that the operation of the pulse power supply box 1 can generate a rapidly rising current to perform high-voltage discharge on the mixed conductive powder 4, thereby converting the amorphous metal into high-entropy metal nanoparticles.

[0036] As another preferred embodiment of the present invention, the pulse power supply box 1 can perform continuous discharge and single discharge.

[0037] As another preferred embodiment of the present invention, the electric pulse characteristics of the pulse power supply box 1 are specifically as follows: the time required for the pulse current to rise from 0A to the set value is less than 10ms, the pulse width can be set to 20-500ms, and the pulse current setting value can be set to 0-500A.

[0038] As another preferred embodiment of the present invention, the insulated high-temperature reaction tube 5 is a reaction vessel that can withstand temperatures above 3000K. The specific material is selected according to needs. Generally speaking, as long as it can withstand temperatures above 3000K, it will suffice.

[0039] Of course, in actual applications, in order to ensure the safety and reliability of the high-voltage discharge process, the insulating high-temperature reaction tube 5 can be made of high-temperature resistant materials such as quartz and polytetrafluoroethylene, with an inner diameter of 5-20 mm and a tube wall of 3-5 mm.

[0040] As another preferred embodiment of the present invention, the first high-voltage electrode 2 and the second high-voltage electrode 7 may be made of conductive solids such as graphite and brass.

[0041] Preferably, the first high-voltage electrode 2 and the second high-voltage electrode 7 are made of brass.

[0042] Preferably, the insulating high-temperature reaction tube 5 is made of polytetrafluoroethylene, has an inner diameter of 5 mm, and a tube wall thickness of 3 mm.

[0043] Another object of the present invention is to provide a method for preparing high-entropy metal nanoparticles, wherein the method adopts the above-mentioned high-entropy metal nanoparticle flash evaporation preparation device, and the method specifically comprises the following steps:

[0044] 1) Fully mixing the reducing conductive carbon black and the metal powder in proportion to obtain a mixed conductive powder 4;

[0045] 2) Weigh and introduce the mixed conductive powder 4 into a clean insulating high-temperature reaction tube 5. Connect the pulsed power supply box 1 to both ends of the insulating high-temperature reaction tube 5 through the first high-voltage electrode 2 and the second high-voltage electrode 7 respectively.

[0046] 3) Set the discharge parameters of the pulsed power supply box 1 to perform high-voltage discharge on the mixed conductive powder 4 to generate high-entropy metal nanoparticles.

[0047] As another preferred embodiment of the embodiment of the present invention, in the method for preparing high-entropy metal nanoparticles, the discharge parameters are a discharge current of 50 - 500 A, a discharge pulse width of 50 - 200 ms, and the number of discharge times is 1 or more.

[0048] As another preferred embodiment of the embodiment of the present invention, in the method for preparing high-entropy metal nanoparticles, it further includes a pretreatment step. The pretreatment step is to ionize the mixed conductive powder 4 under the conditions of a pulsed current of 20 A and a pulse width of 500 ms before high-voltage discharge. Specifically, set the pretreatment pulsed current of the pulsed power supply box 1 to 20 A, the pretreatment pulse width to 500 ms, and the pretreatment discharge number to 5 times to preliminarily ionize the mixed conductive powder 4.

[0049] As another preferred embodiment of the embodiment of the present invention, in the method for preparing high-entropy metal nanoparticles, the mixing of the reducing conductive carbon black and the metal powder in proportion is specifically: the mass ratio of the metal powder to the conductive carbon black is 1.5:1 - 1:1.

[0050] Preferably, the mass ratio of the metal powder to the conductive carbon black is 1.5:1 or 1:1.

[0051] As another preferred embodiment of the embodiment of the present invention, the metal powder can be one or a mixture of Fe, Co, Cu, Zr, Ti, Hf, Nb, Mo, W, Mn.

[0052] As another preferred embodiment of the embodiment of the present invention, specifically, for the metal powder: metals such as Fe, Co, Cu with relatively small oxidation potentials can form high-entropy alloy nanoparticles through high temperature; metals such as Zr, Ti, Hf, Nb with relatively small oxidation potentials can form high-entropy oxide nanoparticles through high temperature; metals such as Mo, W, Mn with medium oxidation potentials can form both high-entropy alloy nanoparticles and high-entropy oxide particles through high temperature.

[0053] As another preferred embodiment of the embodiment of the present invention, in the method for preparing high-entropy metal nanoparticles, it further includes a step of cleaning the insulating high-temperature reaction tube 5.

[0054] As another preferred embodiment of the embodiment of the present invention, the cleaning of the insulated high-temperature reaction tube 5 is specifically as follows: using ionized water and anhydrous ethanol to soak the insulated high-temperature reaction tube 5 clean, and then using an ultrasonic instrument to ultrasonicate for 10 minutes to wash away the dust, dirt and oil stains on the surface of the insulated high-temperature reaction tube 5; the insulated high-temperature reaction tube 5 is turned upside down and placed on absorbent paper to absorb the remaining moisture.

[0055] As another preferred embodiment of the present invention, the method for preparing high-entropy metal nanoparticles specifically includes the following steps:

[0056] 1) Fully mixing the reducing conductive carbon black and the metal powder in proportion to obtain a mixed conductive powder 4;

[0057] 2) weighing the thoroughly mixed conductive powder 4;

[0058] 3) Cleaning the insulated high-temperature reaction tube 5;

[0059] 4) The weighed mixed conductive powder 4 is introduced into a clean insulated high-temperature reaction tube 5. Copper plugs (i.e., a first copper plug 3 and a second copper plug 6) are inserted into the insulated high-temperature reaction tube 5 at both ends. The second copper plug 6 and the first copper plug 3 are respectively inserted into the left and right ends of the insulated high-temperature reaction tube 5 containing the mixed conductive powder 4. The first copper plug 3 and the second copper plug 6 can be pushed into the ends of the mixed conductive powder 4 to fully compress it.

[0060] 5) Place the prepared sample into the device and connect the two ends of the insulated high-temperature reaction tube 5 with wires;

[0061] 6) Set flash evaporation parameters (including pretreatment parameters and discharge parameters);

[0062] 7) After the flash evaporation is completed, take part of the sample for reaction and test the sample.

[0063] The flash evaporation parameters are specifically set as follows: pretreatment parameters: pretreatment pulse current 20A, pretreatment pulse width 500ms, pretreatment times 5 times; discharge parameters: discharge current 50-500A, discharge pulse width 50-200ms, discharge times 1 or more.

[0064] Preferably, the discharge parameters are: discharge current 100A, discharge pulse width 50ms, and discharge number 1 time.

[0065] As another preferred embodiment of the present invention, the method of sufficient mixing can adopt existing technologies, such as mechanical stirring, air flow mixing, etc. The specific process conditions can be selected as needed and will not be described here in detail.

[0066] Further preferably, the method for preparing high entropy metal nanoparticles specifically comprises the following steps:

[0067] 1. Mix the reducing conductive carbon black and metal powder in proportion:

[0068] a) Zero the electronic balance: Place a clean weighing paper in the electronic balance and use the zeroing program to zero it.

[0069] b) Weigh 3 g of the pre-prepared metal powder.

[0070] c) Zero the electronic balance again: Place a clean weighing paper in the electronic balance and use the zeroing program to zero it.

[0071] d) Weigh 2 g of the pre-prepared conductive carbon powder.

[0072] e) Thoroughly mix the weighed metal powder and conductive carbon powder to obtain the mixed conductive powder 4.

[0073] 2. Weigh the thoroughly mixed mixed conductive powder 4:

[0074] a) Zero the electronic balance: Place a clean weighing paper in the electronic balance and use the zeroing program to zero it.

[0075] b) Weigh 0.2 g of the mixed conductive powder 4.

[0076] 3. Clean the insulating high-temperature reaction tube 5.

[0077] 4. Pour the weighed mixed conductive powder 4 into a clean insulating high-temperature reaction tube 5, and use copper plugs to insert into both ends of the insulating high-temperature reaction tube 5. Push the copper plugs into both ends of the mixed conductive powder 4 to make it fully compressed and compact.

[0078] 5. Connect wires to both ends of the insulating high-temperature reaction tube 5 and set the flash evaporation parameters.

[0079] 6. After flash evaporation, take part of the sample for reaction and test the sample.

[0080] The embodiment of the present invention also provides a high-entropy metal nanoparticle prepared by the above-mentioned preparation method of high-entropy metal nanoparticles.

[0081] The embodiment of the present invention also provides an application of the above-mentioned preparation method of high-entropy metal nanoparticles in the processing of nanomaterials.

[0082] The technical effects of the flash evaporation preparation device and preparation method of high-entropy metal nanoparticles in the embodiment of the present invention are further described below by listing specific embodiments.

[0083] Example 1

[0084] A high-entropy metal nanoparticle flash evaporation preparation device, specifically a device for preparing high-entropy metal nanoparticles using flash evaporation technology. The device includes a pulsed power supply box 1. The high-entropy metal nanoparticle flash evaporation preparation device further includes:

[0085] An insulated high-temperature reaction tube 5 for placing a mixed conductive powder 4 to be subjected to high-voltage discharge. Among them, the mixed conductive powder 4 includes conductive carbon black with reducibility and metal powder;

[0086] A first high-voltage electrode 2 and a second high-voltage electrode 7. The pulsed power supply box 1 is respectively connected to both ends of the insulated high-temperature reaction tube 5 through the first high-voltage electrode 2 and the second high-voltage electrode 7 to perform high-voltage discharge on the mixed conductive powder 4 to generate high-entropy metal nanoparticles; and

[0087] A first copper plug 3 and a second copper plug 6. The second copper plug 6 and the first copper plug 3 are respectively inserted into the left and right ends of the insulated high-temperature reaction tube 5 filled with the mixed conductive powder 4 to achieve effective sealing of the insulated high-temperature reaction tube 5; the first high-voltage electrode 2 is clamped at the outer end opening of the first copper plug 3, and the second high-voltage electrode 7 is clamped at the outer end opening of the second copper plug 6;

[0088] Among them, the discharge is to rapidly increase the current to perform high-voltage discharge on the mixed conductive powder 4, so that the mixed conductive powder 4 reaches a temperature above 3000K within less than 100 ms, effectively converting amorphous metal into high-entropy metal nanoparticles; and

[0089] The materials of the first high-voltage electrode 2 and the second high-voltage electrode 7 are selected as brass; the material of the insulated high-temperature reaction tube 5 is selected as polytetrafluoroethylene, with an inner diameter of 5 mm and a tube wall of 3 mm.

[0090] In an embodiment of the present invention, a method for preparing high-entropy metal nanoparticles using the above high-entropy metal nanoparticle flash evaporation preparation device specifically includes the following steps:

[0091] I. Mix the conductive carbon black with reducibility and the metal powder in proportion:

[0092] a) Zero the electronic balance: Place a clean weighing paper in the electronic balance and use the zeroing program to zero it.

[0093] b) Weigh 3 g of pre-prepared metal powder (specifically (CeNiFeCoMn)O x , where x > 0).

[0094] c) Zero the electronic balance again: Place a clean weighing paper in the electronic balance and use the zeroing program to zero it.

[0095] d) Weigh 2 g of pre-prepared conductive carbon powder.

[0096] e) Thoroughly mix the weighed metal powder with conductive carbon powder to obtain mixed conductive powder 4.

[0097] II. Weigh the thoroughly mixed mixed conductive powder 4:

[0098] a) Zero the electronic balance: Place a clean weighing paper inside the electronic balance and use the zeroing program to zero it.

[0099] b) Weigh 0.2 g of mixed conductive powder 4.

[0100] III. Clean the insulating high-temperature reaction tube 5 (made of polytetrafluoroethylene).

[0101] IV. Pour the weighed mixed conductive powder 4 into a clean insulating high-temperature reaction tube 5, and use copper plugs (i.e., the first copper plug 3 and the second copper plug 6) to clip into the insulating high-temperature reaction tube 5 at both ends. Push the copper plugs into both ends of the mixed conductive powder 4 to make it fully compressed and compact.

[0102] V. Connect wires to both ends of the insulating high-temperature reaction tube 5, and set the flash evaporation parameters of the pulsed power supply box 1: pre-treatment pulse current 20 A, pre-treatment pulse width 500 ms, pre-treatment times 5 times; discharge current 100 A, discharge pulse width 50 ms, discharge times 1 time.

[0103] VI. Start flash evaporation (i.e., perform high-voltage discharge on the mixed conductive powder 4 to generate high-entropy metal nanoparticles).

[0104] VII. After flash evaporation, take some of the samples for reaction and test the samples.

[0105] It should be noted that currently the main method for preparing high-entropy metal nanoparticles comes from wet chemical synthesis, in which different particle sizes, shapes, and phases can be obtained. However, most of the research reports on wet chemical methods have alloy compositions of no more than three elements, which limits the composition space. In addition, more site synthesis techniques, including printing- and lithography-based methods, have shifted the composition space to quaternary or even four-nanostructures; however, the subsequent reduction process often limits the structural complexity to phase-separated high-entropy metal nanoparticles, especially for immiscible element combinations. In terms of overall material synthesis, melt processing is a scalable method that results in high-entropy alloys composed of five or more elements in a solid solution (uniform mixture), showing great potential as structural materials. So far, due to the difficulty of mixing elements with greatly different chemical and physical properties and the limitation of the cooling rate, only a limited family of high-entropy alloys has been realized. In addition, it is a difficult task to scale down high-entropy alloys to the nanoscale by traditional alloying methods.

[0106] In the embodiments of the present invention, the preparation of high-entropy metal nanoparticles is achieved by utilizing techniques such as flash Joule heating technology and high-voltage pretreatment technology. The amorphous conductive hybrid powder is compressed between two electrodes and placed in an insulating high-temperature reaction tube 5. The air pressure is maintained at atmospheric pressure. High-voltage discharge causes the hybrid powder to reach a temperature above 3000K in less than 100 milliseconds, effectively converting the amorphous metal into high-entropy metal nanoparticles, enabling precise design and processing of high-entropy metal nanoparticles. Moreover, the preparation method is simple, the controllability can be effectively improved, the production cost is relatively low, it can be used to be mounted on other structures, and the transferability is relatively good.

[0107] Example 2

[0108] Compared with Example 1, the difference in this example lies in the set flash evaporation parameters: the pretreatment pulse current is 20A, the pretreatment pulse width is 500ms, and the number of pretreatment times is 5 times; the discharge current is 120A, the discharge pulse width is 50ms, and the number of discharge times is 1 time.

[0109] Example 3

[0110] Compared with Example 1, the difference in this example lies in the set flash evaporation parameters. The pretreatment pulse current is 20A, the pretreatment pulse width is 500ms, and the number of pretreatment times is 5 times; the discharge current is 150A, the discharge pulse width is 50ms, and the number of discharge times is 1 time.

[0111] Example 4

[0112] Compared with Example 1, the difference in this example lies in the insulating high-temperature reaction tube 5, whose material is selected as polytetrafluoroethylene, the inner diameter is 10mm, and the tube wall is 5mm.

[0113] Example 5

[0114] Compared with Example 1, the difference in this example lies in the insulating high-temperature reaction tube 5, whose material is selected as polytetrafluoroethylene, the inner diameter is 20mm, and the tube wall is 5mm.

[0115] Example 6

[0116] The samples prepared with discharge currents of 100A, 120A, and 150A in Examples 1 - 3 were subjected to TEM (transmission electron microscopy) detection. The obtained TEM images are shown in Figure 2 、 Figure 3 、 Figure 4 respectively. Among them, Figure 2 is the TEM image of the sample prepared with a pulse current of 100A; Figure 3 is the TEM image of the sample prepared with a pulse current of 120A; Figure 4 is the TEM image of the sample prepared with a pulse current of 150A. From Figures 2 - 4It can be seen that high-voltage discharge raises the temperature of the mixed conductive powder 4 to over 3000K in less than 100 milliseconds, effectively converting amorphous metal into high-entropy metal nanoparticles. The high-entropy metal nanoparticles can be precisely designed and processed. The preparation is simple and controllable, with a low cost. It can be mounted on other structures, has good transferability, and realizes the efficient large-scale production of high-entropy metal nanoparticles with uniform particle size and uniform element distribution.

[0117] Example 7

[0118] Compared with Example 1, the difference in this example lies in the set flash evaporation parameters: the pretreatment pulse current is 20A, the pretreatment pulse width is 500ms, and the number of pretreatment times is 5; the discharge current is 1A, the discharge pulse width is 20ms, and the number of discharge times is 1.

[0119] Example 8

[0120] Compared with Example 1, the difference in this example lies in the set flash evaporation parameters: the pretreatment pulse current is 20A, the pretreatment pulse width is 500ms, and the number of pretreatment times is 5; the discharge current is 500A, the discharge pulse width is 500ms, and the number of discharge times is 1.

[0121] Example 9

[0122] Compared with Example 1, the difference in this example lies in the set flash evaporation parameters: the pretreatment pulse current is 20A, the pretreatment pulse width is 500ms, and the number of pretreatment times is 5; the discharge current is 300A, the discharge pulse width is 100ms, and the number of discharge times is 1.

[0123] Example 10

[0124] Compared with Example 1, the difference in this example lies in the insulating high-temperature reaction tube 5, whose material is selected as polytetrafluoroethylene, with an inner diameter of 5mm and a tube wall thickness of 3mm.

[0125] Example 11

[0126] Compared with Example 1, except for weighing 3g of pre-prepared conductive carbon powder, the others are the same as in Example 1.

[0127] Example 12

[0128] Compared with Example 1, except that the pre-prepared metal powder is specifically (CeNiFeCoMo)O x (where x > 0), the others are the same as in Example 1.

[0129] Example 13

[0130] Compared with Example 1, except that the pre-prepared metal powder is specifically (CuNiFeCoMo)Ox (where x > 0), and the rest is the same as in Example 1.

[0131] Example 14

[0132] Compared with Example 1, except that the pre-prepared metal powder is specifically (CuTiFeCoMo)O x (where x > 0), and the rest is the same as in Example 1.

[0133] In summary, the high-entropy metal nanoparticle flash evaporation preparation device provided by the embodiments of the present invention is based on the use of conductive mixed powder and flash Joule heating technology. The conductive mixed powder is preliminarily ionized by using a high-voltage pretreatment method. Then, by using the high voltage, high heat, and high pressure of flash Joule heating, ordinary metal powder is converted into high-entropy metal nanoparticles. By controlling the number of pretreatment times, voltage, power, time, etc., the desired high-entropy metal nanoparticles can be obtained, solving the problem that the existing traditional preparation technology of high-entropy metal nanoparticles cannot efficiently produce high-entropy metal nanoparticles on a large scale, and having a broad market prospect. The high-entropy metal nanoparticle preparation method provided by the embodiments of the present invention is specifically a method for preparing high-entropy alloys using flash evaporation technology. By setting two electrodes connected to the power supply cabinet and using these electrodes to perform high-voltage discharge on the raw materials placed in the insulated high-temperature reaction tube, the high-voltage discharge of the capacitor bank enables the mixed powder to reach a temperature above 3000K in less than 100 ms, effectively converting amorphous metal into high-entropy metal nanoparticles. The whole process only consumes electricity, has low production costs, and a fast production speed, providing a new process method for large-scale production of high-entropy metals.

[0134] In the description of the embodiments of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific situations.

[0135] The standard parts used in the embodiments of the present invention can all be purchased from the market. The special-shaped parts can be customized according to the description of the specification and the drawings. The specific connection methods of each part can all adopt conventional means such as bolts, rivets, and welding that are mature in the existing technology, and will not be elaborated here.

[0136] The above has described the preferred embodiments of the present invention in detail. However, the above embodiments are only used to illustrate the technical solutions of the embodiments of the present invention, rather than limiting them; although the embodiments of the present invention have been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present invention. And the obvious changes or variations derived therefrom are still within the protection scope of the embodiments of the present invention.

Claims

1. A method for preparing high-entropy metal nanoparticles, using a high-entropy metal nanoparticle flash evaporation preparation device, characterized in that: The high-entropy metal nanoparticle flash evaporation preparation device includes a pulsed power supply box (1) and an insulated high-temperature reaction tube (5) for placing a mixed conductive powder (4) to be subjected to high-voltage discharge. Among them, the mixed conductive powder (4) includes conductive carbon black with reducibility and metal powder, and the metal powder is specifically (CeNiFeCoMn)O x , or (CuNiFeCoMo)O x or (CuTiFeCoMo)O x , where x > 0; It further includes a first high-voltage electrode (2) and a second high-voltage electrode (7). The pulsed power supply box (1) is respectively connected to both ends of the insulated high-temperature reaction tube (5) through the first high-voltage electrode (2) and the second high-voltage electrode (7) to discharge and generate high-entropy metal nanoparticles by high-voltage discharge of the mixed conductive powder (4); The high-entropy metal nanoparticle flash evaporation preparation device further includes a first copper plug (3) and a second copper plug (6). The second copper plug (6) and the first copper plug (3) are respectively inserted into the left and right ends of the insulated high-temperature reaction tube (5) containing the mixed conductive powder (4). The first high-voltage electrode (2) is clamped at the outer opening of the first copper plug (3), and the second high-voltage electrode (7) is clamped at the outer opening of the second copper plug (6). By pushing the first copper plug 3 and the second copper plug 6 into both ends of the mixed conductive powder 4, the mixed conductive powder (4) is fully compressed and compacted; The method for preparing high-entropy metal nanoparticles includes the following steps: fully mixing the reducing conductive carbon black and metal powder in proportion to obtain the mixed conductive powder (4); weighing the mixed conductive powder (4) and introducing it into a clean insulated high-temperature reaction tube (5), and connecting the pulsed power supply box (1) to both ends of the insulated high-temperature reaction tube (5) through the first high-voltage electrode (2) and the second high-voltage electrode (7) respectively; setting the discharge parameters of the pulsed power supply box (1) to generate high-entropy metal nanoparticles by high-voltage discharge of the mixed conductive powder (4); the discharge parameters are a discharge current of 50 - 500 A, a discharge pulse width of 50 - 200 ms, and the number of discharge times is 1 or more; It further includes a pretreatment step, and the pretreatment step is to ionize the mixed conductive powder under the conditions of a pulsed current of 20 A and a pulse width of 500 ms before high-voltage discharge.

2. The method for preparing high-entropy metal nanoparticles according to claim 1, wherein, The electrical pulse characteristics of the pulsed power supply box (1) are specifically: the time required for the pulsed current to rise from 0 A to the set value is less than 10 ms, the pulse width is 20 - 500 ms, and the set value of the pulsed current is 0 - 500 A.

3. The method for preparing high-entropy metal nanoparticles according to claim 1, wherein The inner diameter of the insulated high-temperature reaction tube (5) is 5 - 20 mm, and the tube wall is 3 - 5 mm.

4. The preparation method of the high-entropy metal nanoparticles according to claim 1, characterized in that, In the method for preparing high-entropy metal nanoparticles, the mass ratio of the metal powder to the conductive carbon black is 1.5:1 - 1:

1.

5. An application of the method for preparing high-entropy metal nanoparticles as described in claim 1 in nanomaterial processing.

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