High-entropy material preparation heating device and method

Abstract

The invention provides a high-entropy material preparation heating device which comprises a box body, and a particle distribution homogenizer, a heating assembly and a material receiver are sequentially arranged in the box body from top to bottom. The heating device further comprises a vibration assembly and a control unit. The particle distribution homogenizer comprises a screen positioned on the upper layer and a partition plate positioned on the lower layer, and an electric control valve is arranged on the partition plate; the heating assembly consists of a plurality of layers of resistance wires with adjustable height intervals; the material receiver is used for collecting the heated powder material; the vibration assembly is used for generating vibration with preset frequency and amplitude; the control unit is used for controlling the opening and closing of an electric control valve of the particle distribution homogenizer; the adjusting module is used for adjusting voltage, current and time of resistance wire heating of the heating assembly; the vibration assembly is controlled to generate vibration. The invention further provides a preparation method of the high-entropy material, high-entropy oxide precursor powder passes through a heating zone through free falling motion, and the high-entropy oxide is obtained. According to the method, rapid, efficient and controllable preparation of the high-entropy material can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of high entropy materials, and in particular to a heating device and method for preparing high entropy materials. Background Art

[0002] In the preparation process of high-entropy materials, in order to promote the full diffusion and uniform mixing of multi-component elements, the powder raw materials usually need to be subjected to high-temperature heat treatment. Especially in the rapid preparation technology of high-entropy materials (such as spark plasma sintering, self-propagating high-temperature synthesis, etc.), the powder raw materials are often required to undergo rapid heating, short-term high-temperature residence and rapid cooling to control the microstructure, avoid phase separation and form a stable new phase structure.

[0003] Existing powder heating technologies primarily include fluidized bed heaters, contact conduction heating, microwave or high-frequency electric field heating, infrared radiation heating, and induction heating. Fluidized bed heaters transfer heat through suspended contact between high-temperature gas and powder, maintaining a fluidized and mixed state during the heating process. Contact conduction heating involves direct contact between the heating medium and the powder to transfer heat. Microwave or high-frequency electric field heating relies on electromagnetic fields to heat the interior of the powder and is suitable for powder materials with strong polarity or high dielectric loss. Infrared radiation heating uses radiant energy to heat the powder surface and is typically used for materials with small, well-dispersed particles. Induction heating utilizes an alternating magnetic field to induce eddy currents within the conductive powder to achieve rapid heating. Although these heating technologies have been applied in various powder processing processes, they still have significant limitations in terms of heating speed, temperature uniformity, and process flexibility in adapting to the preparation of high-entropy materials.

[0004] Specifically, fluidized bed and contact heating methods are limited by the heat transfer rate at the gas-solid interface or solid-solid interface, making it difficult to achieve rapid heating and cooling in milliseconds to seconds; microwave or high-frequency electric field heating is highly sensitive to the dielectric properties of the powder, and there are problems such as uneven heating area, local overheating, and difficulty in temperature control; infrared radiation heating mainly heats the surface layer, making it difficult to achieve rapid and uniform heating inside the particles; induction heating is only suitable for conductive or magnetic powders and is ineffective for non-conductive powders. In addition, existing heating devices generally have the problem of uneven temperature field distribution, making it difficult to accurately control the heating process, and the heating elements have limited temperature resistance, making it difficult to meet the requirements of stable operation at higher temperatures. At the same time, the existing heating system has a complex structure, the heating method is usually fixed, and there is a lack of flexible switching capabilities between different heating methods, making it difficult to achieve large-scale continuous production. Therefore, existing technologies are difficult to meet the actual needs of fast, efficient, and controllable preparation of high-entropy materials. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention proposes a high-entropy material preparation heating device and method to solve the technical problems in the existing technology that are difficult to meet the requirements of fast, efficient and controllable preparation of high-entropy materials.

[0006] The technical solution adopted in the present invention is as follows: In a first aspect, a method for preparing a high-entropy material is provided, comprising: free-falling a high-entropy oxide precursor powder through a heating zone to produce the high-entropy oxide. Beneficial technical effects include: utilizing a non-contact, free-fall rapid heating structure, where the powder passes through a multi-layered resistance wire radiant heating zone during its fall, achieving direct and rapid heating at the particle level, avoiding lag caused by heat transfer across solid walls.

[0007] Furthermore, the heating zone can be configured to operate in a constant temperature heating mode, a pulse heating mode, or a combination of a constant temperature heating mode and a pulse heating mode. Beneficial technical effects include: the ability to create both a near-constant temperature field and a localized pulsed temperature difference field, providing flexibility in the heating process and facilitating precise control of the thermal behavior of the particles.

[0008] Furthermore, as the high-entropy oxide precursor powder freely falls through the heating zone, the heating zone vibrates, driving the powder to vibrate. Beneficial technical effects include: during the heating process, the vibration of the heating assembly not only drives the powder smoothly through the heating zone, but also enhances the dispersion and heating uniformity of the powder, preventing accumulation and sintering.

[0009] Furthermore, the preparation method of the high entropy oxide precursor powder is as follows: using a bubble template of a polymer foam stabilizer, the metal salt complex liquid is evenly mixed and co-precipitated to form a polymer colloid; the polymer colloid is freeze-dried to obtain a high entropy precursor; a precipitant is added to the high entropy precursor, and the high entropy oxide precursor powder is obtained after grinding and mixing.

[0010] Furthermore, a bubble template of a polymer foam stabilizer is used to uniformly mix and co-precipitate a metal salt complex solution to form a polymer colloid. This process involves adding at least five metal salts to a solvent, then adding a complexing agent and a foam stabilizer to obtain a metal salt complex solution, and adjusting the pH of the metal salt complex solution; and aerating the metal salt complex solution with an inert gas to cause instantaneous mixing and co-precipitation of the microbubble interface to form a polymer colloid. Beneficial technical effects include avoiding macroscopic pH fluctuations and localized ion supersaturation caused by the batch addition of alkali solution, eliminating the possibility of early generation of enriched phases, coarse particles, and agglomerate nuclei. Furthermore, the extremely high specific interfacial area and millisecond-level update rate provided by the microbubbles significantly shorten the diffusion path, allowing the entire deposition-drying process to be completed within minutes. This process is energy-efficient and scale-up-friendly, with overall uniformity and controllability far superior to traditional technical routes. The above method is used to prepare high-entropy oxide precursor powder, and the deposition reaction is confined to the continuously renewed microbubble interface, which significantly improves the mixing efficiency and nucleation uniformity of multi-metal ions. The precursor particles have regular morphology, low agglomeration, and the element distribution tends to an ideal random state; interfacial shear replaces bulk titration to avoid sudden pH changes in the system and local ion supersaturation, so that the entire deposition-drying process can be completed under milder and controllable conditions, reducing the energy consumption and grain coarsening risks caused by high temperature or long-term treatment; the specific surface area and the number of active sites of the obtained powder are greatly improved, providing sufficient diffusion channels for subsequent rapid solid-phase reactions, which is conducive to obtaining sodium ion high-entropy layered oxides with better crystal integrity, higher phase purity and more stable electrochemical properties.

[0011] In a second aspect, a high-entropy material preparation heating device is provided, which is used to implement the high-entropy material preparation method described in the first aspect, comprising: a box, wherein a particle distribution homogenizer, a heating component, and a material receiver are sequentially arranged inside the box from top to bottom; the heating device also includes a vibration component and a control unit; A particle distribution homogenizer comprises a screen at an upper layer and a partition at a lower layer, wherein an electric control valve is provided on the partition; The heating assembly consists of multiple layers of resistance wires with adjustable height spacing; A material receiver is used to collect the powder material after heating treatment; A vibration component for generating vibration of a preset frequency and amplitude; The control unit is electrically connected to the particle distribution homogenizer, heating component, and vibration component, and is used to control the opening and closing of the electrically controlled valve of the particle distribution homogenizer; to adjust the voltage, current, and time of the heating element's resistance wire heating; and to control the vibration of the vibration component. Beneficial technical effects include: enabling continuous release-continuous heating-continuous collection process control, suitable for large-scale preparation, and particularly adaptable to micro-nanopowder particles; and offering outstanding advantages such as fast heating speed, high temperature uniformity, flexible heating methods, no contact contamination, strong material adaptability, controllable production process, feasibility of continuous large-scale production, and stable and reliable equipment.

[0012] Furthermore, when the interlayer spacing of the resistance wires is consistent, a nearly constant temperature field is formed; when the interlayer spacing is inconsistent, a pulsed temperature difference field is formed. Beneficial technical effects include: by adjusting the interlayer spacing of the resistance wires, a constant temperature field and a pulsed temperature difference field can be easily constructed.

[0013] Furthermore, the resistance wire is supported and electrically isolated by a high-temperature resistant ceramic column; conductive leads or electrode structures are provided at both ends of the resistance wire; the conductive leads or electrode structures are fixed by a high-temperature insulating clamp and connected to an external power source; and the conductive leads or electrode structures are made of high-temperature resistant and corrosion-resistant materials. Beneficial technical effects include: using high-temperature resistant metal leads to connect the resistance wire, and providing a wire transition structure between the high-temperature zone and the low-temperature zone, so that the power supply connection is safe and stable, and can adapt to long-term continuous operation in a high-temperature environment, avoiding the problem of wire melting, oxidation, or failure at high temperatures, and ensuring the durability and safety of the system operation.

[0014] Furthermore, the vibration assembly is supported on the internal frame of the box via a flexible connection, and an integrated bracket connects the vibration assembly to the material receiver, heating assembly, and particle distribution homogenizer to form a single unit. Beneficial technical effects include achieving synchronized micro-vibration of the entire heating assembly and particle homogenizer, promoting uniform flow and heating of the powder.

[0015] Furthermore, the chamber is equipped with an inert gas atmosphere control system, which includes an air inlet valve, an air extraction valve, a multi-function three-way valve, and a pressure gauge. Beneficial effects include: the apparatus's free-fall, baseless structure prevents contamination of the vessel walls and crucible, while the sealed atmosphere control system within the apparatus enhances the purity and stability of material synthesis. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly describes the drawings required for the specific embodiments or the description of the prior art. Similar elements or parts are generally identified by similar reference numerals throughout the drawings. Elements or parts in the drawings are not necessarily drawn to scale.

[0017] Figure 1 This is a schematic structural diagram of a heating device according to an embodiment of the present invention; Figure 2 A side view of the resistance wire arrangement of a heating assembly according to an embodiment of the present invention; Figure 3 The heating temperature control curve of the heating area of ​​the embodiment of the present invention; Figure 4 This is an X-ray diffraction analysis result of a high entropy oxide prepared by the heating method according to an embodiment of the present invention; Reference numerals: 1-particle distribution homogenizer, 2-heating component, 21-resistance wire, 3-material receiver, 4-vibration component, 5-box, 6-feed port. DETAILED DESCRIPTION

[0018] The following embodiments of the technical solution of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention and are therefore only examples and are not intended to limit the scope of protection of the present invention.

[0019] It should be noted that, unless otherwise specified, the technical or scientific terms used in this application should have the common meanings understood by those skilled in the art to which the present invention belongs.

[0020] Example The controllability of the powder heating technology for preparing high entropy materials is reflected in the heating rate, temperature uniformity, temperature limit, cooling rate and process flexibility. Combined with the demand for fast, efficient and continuous preparation capabilities, this embodiment provides a high entropy material preparation heating device suitable for non-conductive powder materials, such as Figure 1 As shown, it includes a box body 5 with a feed port 6 on the top, and a particle distribution homogenizer 1, a heating component 2, and a material receiver 3 arranged in sequence from top to bottom inside the box body; the heating device also includes a vibration component 4 and a control unit.

[0021] The particle distribution homogenizer 1 is arranged at the top of the box body, and includes a screen located on the upper layer and a partition located on the lower layer, and an electric-controlled valve is provided on the partition. In some embodiments, the screen is connected to the vibration component in a transmission manner, and vibrates slightly synchronously with the vibration component to prevent material accumulation and achieve uniform material dropout; the transmission connection method is not limited, and any feasible method in the prior art can be used, such as using a cam mechanism, with the screen as a follower. The electric-controlled valve is electrically connected to the control unit, and the opening and closing size of the electric-controlled valve is adjusted by the control unit. In some embodiments, the partition is tightly attached to the bottom of the screen; it can better achieve the effect of uniform particle dispersion. Preferably, the screen and the partition are made of high-temperature corrosion-resistant metal to reduce the aging effect caused by the high temperature below the particle distribution homogenizer during the operation of the equipment.

[0022] The heating component 2 is located below the particle distribution homogenizer, such as Figure 2As shown, it is composed of multiple layers of resistance wire 21 with adjustable height spacing, and each layer of resistance wire is supported and electrically isolated by a high-temperature resistant ceramic column. Conductive leads or electrode structures are set at both ends of the resistance wire, and the conductive leads or electrode structures are made of high-temperature resistant and corrosion-resistant materials (such as carbon blocks); the conductive leads or electrode structures are fixed by high-temperature insulating clamps and connected to an external power supply to realize current input. The implementation method of the high-temperature insulating clamp is not limited and can be implemented in any feasible way in the prior art, such as a ceramic snap-on clamp. High-temperature resistant metal leads are used to connect the resistance wires, and a wire transition structure is set between the high-temperature zone and the low-temperature zone, so that the power connection is safe and stable, and can adapt to long-term continuous operation in a high-temperature environment, avoiding the problem of wire melting, oxidation or failure at high temperatures, and ensuring the durability and safety of the system operation.

[0023] The material of the resistance wire can be changed to suit different synthesis scenarios. For example, molybdenum and tungsten wires with excellent oxidation resistance are used for high-entropy oxide synthesis to prevent sample reduction or contamination at high temperatures. Carbon fiber can be used for high-entropy alloy preparation. As the powder free-falls through the resistance wire heating zone of the heating assembly, adjusting the spacing of the resistance wires can create either a near-constant temperature field or a localized pulsed temperature field. This allows for flexible implementation of either constant-temperature heating or pulsed heating / cooling processes to meet the heating requirements of different thermal histories. Specifically, consistent spacing between the resistance wire layers creates a near-constant temperature field; inconsistent spacing, such as a dense section and a loose section, creates a pulsed temperature field. Adjusting the spacing between the resistance wire layers allows for convenient configuration of both constant and pulsed temperature fields. The heating mode is determined by the spacing between the resistance wire layers. When the spacing between the layers is consistent, the heating area is in constant-temperature mode; when the spacing between the layers is inconsistent, the heating area is in pulsed mode. When the powder passes through the heating zone, the heating modes it may experience include a constant temperature heating mode throughout the entire process, a pulse heating mode throughout the entire process, or a constant temperature heating mode in some areas and a pulse heating mode in some areas.

[0024] The material collector 3, located below the heating element, collects the heated powdered material. Made of high-temperature-resistant ceramic or heat-resistant metal, it ensures thermal stability and chemical inertness during the collection process. Its shape and size are not limited; it can fit within the box and must be at least the same size as the heating element.

[0025] The vibration component 4 is used to generate a slight vibration with a frequency of 20 to 100 Hz and an amplitude of 0.1 to 0.5 mm. In some embodiments, the vibration component can be arranged on the partition to only drive the screen to vibrate slightly, which is convenient for airtightness control. In other embodiments, the vibration component can be arranged below the material receiver, supported on the internal frame of the box through a flexible connection, and then the vibration component is connected to the material receiver, the heating component and the particle distribution homogenizer as a whole through an integrated bracket. In this way, the entire heating component and the particle homogenizer can be synchronously vibrated slightly to promote uniform flow and heating of the powder. In a specific embodiment, the implementation method of the slight vibration of the vibration component is not limited and can be implemented in any feasible manner in the prior art, such as by rotating the motor through the transmission rod to drive the eccentric wheel to rotate, thereby generating slight vibration. Preferably, the vibration component is made of a high-temperature resistant metal material, such as a nickel-based alloy (Inconel).

[0026] The box 5 is equipped with an atmosphere control system, which includes an inert gas inlet valve, an exhaust valve, a multi-function three-way valve and a pressure gauge. The inert gas is preferably argon. The heating device can continuously inject argon into the box as needed during operation to maintain the atmosphere of the high entropy material during the preparation process. In some embodiments, a detection interface for inserting a temperature probe is provided on the outer wall of the box to monitor the temperature of the heating area in real time. Preferably, the box is made of high-temperature insulation material, and the temperature range is designed to be 1000-1500°C.

[0027] The control unit, while not specifically positioned within the chamber, is located at the bottom of the chamber in some embodiments and is electrically connected to the particle distribution homogenizer, heating assembly, and vibration assembly. It is used to: open and close the electrically controlled valve of the particle distribution homogenizer to precisely manage material release timing; control the constant-current regulated power supply of the heating assembly to adjust the voltage, current, and duration of the resistance wire heating; and control the speed of the eccentric motor to adjust the vibration frequency and amplitude. The control unit is equipped with a human-machine interface (e.g., a touch screen or button panel) that allows real-time adjustment of heating parameters and supports both manual and pre-programmed control modes. The implementation of this human-machine interface is not specifically defined and may be implemented in any manner practicable in the prior art.

[0028] When using this heating device, the particle distribution homogenizer, heating assembly, and vibration assembly can utilize three independent power switches to achieve continuous release, continuous heating, and continuous collection process control. Specifically, the prepared high-entropy material precursor powder is added to the feed port at the top of the chamber. After vibration homogenization, the powder feed rate is controlled by an electronically controlled valve, causing the powder to free fall through heating zones with set temperatures and layer spacing. During its passage through the heating zones, the powder particles rapidly heat up and undergo multiple stages of heat treatment depending on the heating mode (constant temperature or pulsed). The gentle vibrations generated by the vibration assembly ensure that the powder does not stagnate or adhere during the heating process. The heated high-entropy product is finally received by a receiver. This entire process can be carried out under an inert atmosphere (such as Ar or N2) or a specific atmosphere.

[0029] In order to verify the applicability and efficiency of the device of the present invention, the high entropy layered oxide material Na x Mn 0.2 Fe 0.2 Ni 0.1 Cu 0.1 Mg 0.1 Zn 0.1 This example provides a method for preparing and heating high-entropy materials, using O2 as a representative example. This method also involves conducting rapid thermal processing experiments using a heating device to prepare high-entropy materials. This type of material has been widely studied in recent years as a cathode material for sodium-ion batteries due to its structural stability and rich component configuration.

[0030] The heating method comprises the following steps: S1. Using a bubble template of a polymer foam stabilizer, the metal salt complex liquid is quickly and evenly mixed and co-precipitated to form a polymer colloid, and the polymer colloid is freeze-dried to prepare a high entropy oxide precursor powder. Preparation of metal salt complex solution: weigh Na2CO3, Ni(NO3)2, Mn(NO3)2, Fe(NO3)3, Cu(NO3)2, Mg(NO3)2, Zn(NO3)2, and add them into deionized water at a molar ratio of Mn:Fe:Ni:Cu:Mg:Zn=0.2:0.2:0.1:0.1:0.1:0.1 (total metal ion concentration 0.8 mol·L -1), citric acid (citric acid / metal molar ratio 1.0) as a complexing agent and 0.8wt% PVA-PVP (1:1) as a foam stabilizer were added to obtain a metal salt complex solution, and the pH of the metal salt complex solution was adjusted to 6.5 by adding acid or alkali; then the metal salt complex solution was aerated for 3 minutes by passing an inert gas (such as N2, 0.10MPa, gas-liquid flow ratio 1:50) through a ceramic aerator with an average pore size of 25µm to allow instantaneous mixing and co-precipitation at the microbubble interface to form a polymer colloid. After standing for 2 minutes, the colloid was quickly frozen at -40℃ for 2 hours and freeze-dried at 10Pa for 24 hours to obtain high entropy TM(OH) x Precursor. A precipitant is then added, and NaCO3 is weighed at a Na / TM ratio of 1.05:1. After grinding and mixing, a precursor powder is obtained. Those skilled in the art should be aware that the components and ratios of the above-mentioned substances in the preparation of polymer colloids are illustrated by preferred embodiments and do not limit the technical solutions of this application.

[0031] The microporous aerator continuously generates uniform microbubbles in the liquid phase, making the gas / liquid interface the main nucleation and deposition site of the multimetallic complexes. The high shear and Marangoni convection generated by the rising and instantaneous bursting of the bubbles rapidly mix the transition metal ions at the nanoscale and simultaneously deposit them as TM(OH) x colloids, thereby obtaining high-entropy precursors in one go. Compared with existing mechanical stirring co-precipitation or sol-gel processes, the reaction field of this method is transferred from the "bulk phase" to the "gas-liquid interface", avoiding the macroscopic pH fluctuations and local ion supersaturation caused by the batch addition of alkali solution, and eliminating the possibility of early generation of enriched phases, coarse particles and agglomerate nuclei; at the same time, the extremely high specific interface area and millisecond-level update rate provided by microbubbles significantly shorten the diffusion path, allowing the entire deposition-drying process to be completed within a few minutes, with low energy consumption and friendly scale-up. The overall uniformity and controllability are far superior to traditional technical routes.

[0032] The above method is used to prepare high-entropy oxide precursor powders, confining the deposition reaction to the continuously renewed microbubble interface. This significantly improves the mixing efficiency and nucleation uniformity of multi-metal ions, resulting in regular precursor particle morphology, low agglomeration, and an ideal random element distribution. Interfacial shearing replaces bulk titration to avoid sudden pH changes and local ion supersaturation in the system, allowing the entire deposition-drying process to be completed under milder and more controllable conditions, reducing the energy consumption and risk of grain coarsening caused by high temperature or prolonged treatment. The resulting powder has a significantly increased specific surface area and number of active sites, providing ample diffusion channels for subsequent rapid solid-phase reactions, helping to obtain sodium ion high-entropy layered oxides with better crystal integrity, higher phase purity, and more stable electrochemical properties. Furthermore, the equipment used is a conventional aeration and freeze-drying unit, which facilitates scale-up and reduces production costs.

[0033] S2. The high entropy oxide precursor powder is passed through the heating zone by free fall to obtain high entropy oxide. The dried precursor powder was heated to the feed port at the top of the device. The vibration assembly was activated, with a frequency of 30 Hz and an amplitude of 0.2 mm, to achieve uniform particle dispersion. Simultaneously, the electrically controlled valve on the partition was opened, and the release port size was adjusted to 3 mm to release the material.

[0034] The powder enters the heating component in a free-falling state under vibration and passes through the heating zone formed by multiple layers of resistance wire. The heating zone can achieve a maximum temperature of 1300°C. The temperature control of the heating zone adopts a thermocouple feedback closed-loop control system. The actual curve is as follows Figure 3 As shown, it only takes a few seconds to heat up to 1200°C, and then the temperature can be maintained constant; it only takes a few hundred milliseconds for the powder to enter the heating zone and be heated to form a high-entropy oxide at high temperature, so the height of the heating zone in the heating device can be controlled within 1 meter; when the powder heating is completed, the system cools down rapidly. By setting a multi-layer resistance wire heating structure with adjustable spacing, and combining the method of free fall of powder through the heating zone, high-speed heating and cooling of the powder can be achieved. The temperature distribution during the heating process is controllable and uniform, and the heating method is flexible. The spacing of the multi-layer resistance wire can be adjusted as needed, and the constant temperature heating and pulse heating modes can be switched, giving the heating process flexibility, which helps to accurately control the thermal behavior of the particles, effectively promotes the full diffusion and uniform mixing of multi-component elements, and increases the possibility of forming a stable new high-entropy phase structure, thereby helping to optimize the microstructure and properties of the material. Compared with the traditional high-temperature carbon thermal shock method that relies on base materials such as carbon cloth and carbon felt for heating, it is easy to cause sample reduction at high temperatures and affect the preparation of materials such as high-entropy oxides. This embodiment utilizes independent resistance wire heating, and the material of the resistance wire can be flexibly changed to suit different synthesis scenarios (e.g., high-entropy alloys or high-entropy oxides), effectively preventing the reduction of the carbon substrate from interfering with sample purity and structure. A non-contact, free-fall rapid heating structure allows the powder to fall through a multi-layered resistance wire radiant heating zone, achieving direct and rapid heating at the particle level, avoiding the lag caused by heat transfer across solid walls.

[0035] The heating device utilizes a free-fall, baseless structure to prevent contamination of the vessel walls and crucible. It also features a sealed atmosphere control system to enhance the purity and stability of material synthesis. During the heating process, the vibrating heating element not only propels the powder through the heating zone but also enhances material dispersion and heating uniformity, preventing accumulation and sintering.

[0036] In order to achieve precise temperature control of the powder during free fall, a thermocouple feedback closed-loop control system can also be introduced into the heating device. The system monitors the local temperature in real time through high-temperature thermocouples arranged in the heating zone, and cooperates with the high-response PID control module to realize automatic adjustment of the input current and voltage of the heating resistor, thereby accurately controlling the target temperature. Compared with the traditional heating method that requires manual adjustment of voltage and current, this system greatly improves the stability and response speed of temperature control, and is especially suitable for rapid heating and instantaneous constant temperature scenarios. At the same time, in order to enhance the flexibility of the heating strategy, the system retains programmable voltage and current control channels, allowing operating strategies such as pulse heating, linear or nonlinear heating curves to be set as needed. This closed-loop control structure not only achieves precise and stable temperature control, but also provides a highly free control platform for thermal field optimization during the synthesis of multi-component powder materials.

[0037] The high entropy oxide is prepared and falls into the material receiver by inertia. In some embodiments, the material receiver is connected to the corundum collection tube outside the box, and can be sent to the sample bottle for sealed storage by means of positive pressure purge of inert gas. The final product is a high entropy layered oxide powder with uniform color and particle size, and no obvious agglomeration. X-ray diffraction analysis shows that the material is not oxidized. Figure 4 It can be seen that the target material is a single-phase R-3m layered structure, which is consistent with the characteristics of high-entropy sodium-ion battery positive electrode materials.

[0038] The use of this device can significantly improve the heating efficiency and temperature uniformity of powders in a short period of time, enhance the diffusion and solid solution reaction between multiple components, and facilitate the formation of a stable high-entropy phase structure. The materials of all components in the device are high-temperature resistant and corrosion-resistant materials, and can work stably at 1000~1500℃ for a long time, adapting to the heat treatment needs of various powders. Compared with traditional intermittent furnace heating or contact Joule heating methods, the present invention has the advantages of fast heating, continuous process, low pollution, wide adaptability, high energy efficiency, and simple operation. It is particularly suitable for the rapid synthesis of high-performance high-entropy materials and related process research and engineering scale-up.

[0039] The above-described heating device and method for preparing high-entropy materials enables a controlled process of continuous release, continuous heating, and continuous collection, making it suitable for large-scale preparation and particularly adaptable to micro- and nanoparticle powders. It boasts outstanding advantages such as fast heating, high temperature uniformity, flexible heating methods, zero contact contamination, strong material adaptability, controllable production processes, feasibility of continuous scalability, and stable and reliable equipment. It provides a new technological platform for the efficient preparation of high-entropy materials and other high-performance functional powders, with broad application prospects and industrial promotion value.

[0040] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and description of the present invention.

Claims

1. A method for preparing a high entropy material, characterized in that: include: The high entropy oxide precursor powder is passed through a heating zone by free fall to obtain the high entropy oxide.

2. The method for preparing high entropy materials according to claim 1, wherein: The heating zone is configured as a constant temperature heating mode, a pulse heating mode, or a constant temperature heating combined with a pulse heating mode.

3. The method for preparing high entropy materials according to claim 1, wherein: When the high entropy oxide precursor powder passes through the heating zone by free fall, the heating zone is in a vibrating state, driving the powder to vibrate.

4. The method for preparing high entropy materials according to claim 1, wherein: The high entropy oxide precursor powder is prepared as follows: Using the bubble template of the polymer foam stabilizer, the metal salt complex liquid is evenly mixed and co-precipitated to form a polymer colloid; The high entropy precursor is obtained by freeze-drying the polymer colloid; A precipitant is added to the high entropy precursor, and the mixture is ground and mixed to obtain a high entropy oxide precursor powder.

5. The method for preparing high entropy materials according to claim 4, characterized in that: Using the bubble template of the polymer foam stabilizer, the metal salt complex liquid is evenly mixed and co-precipitated to form a polymer colloid, including: Adding at least five metal salts to a solvent, and then adding a complexing agent and a foam stabilizer to obtain a metal salt complex solution, and adjusting the pH value of the metal salt complex solution; The metal salt complex liquid is aerated with an inert gas to cause instantaneous mixing and co-deposition of the microbubble interface to form a polymer colloid.

6. A high entropy material preparation heating device, characterized in that: A method for preparing a high-entropy material according to any one of claims 1 to 5, comprising: a box, wherein a particle distribution homogenizer, a heating component, and a material receiver are sequentially arranged inside the box from top to bottom; the heating device further comprising a vibration component and a control unit; A particle distribution homogenizer comprises a screen at an upper layer and a partition at a lower layer, wherein an electric control valve is provided on the partition; The heating assembly consists of multiple layers of resistance wires with adjustable height spacing; A material receiver is used to collect the powder material after heating treatment; A vibration component for generating vibration of a preset frequency and amplitude; The control unit is electrically connected to the particle distribution homogenizer, the heating component and the vibration component respectively, and is used to control the opening and closing of the electric control valve of the particle distribution homogenizer; to adjust the voltage, current and time of the resistance wire heating of the heating component; and to control the vibration of the vibration component.

7. The high entropy material preparation heating device according to claim 6, characterized in that: When the interlayer spacing of the resistance wires is consistent, an approximately constant temperature field is formed; when the interlayer spacing is inconsistent, a pulse temperature difference field is formed.

8. The high entropy material preparation heating device according to claim 6, characterized in that: The resistance wire is supported and electrically isolated by a high-temperature resistant ceramic column; conductive leads or electrode structures are set at both ends of the resistance wire; the conductive leads or electrode structures are fixed by high-temperature insulating clamps and connected to an external power supply; the conductive leads or electrode structures are made of high-temperature resistant and corrosion-resistant materials.

9. The high entropy material preparation heating device according to claim 6, characterized in that: The vibration component is supported on the internal frame of the box through a flexible connection, and the vibration component is connected to the material receiver, the heating component and the particle distribution homogenizer into a whole through an integrated bracket.

10. The high entropy material preparation heating device according to claim 6, characterized in that: The box is also equipped with an inert gas atmosphere control system, which includes an air inlet valve, an air extraction valve, a multifunctional three-way valve and a pressure gauge.

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