Integrated ultrasonic atomization-chemical vapor deposition preparation device

Abstract

This invention discloses an integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation device for preparing particles with a metal core and a CVD shell structure. The device includes a feeder, an ultrasonic atomization system, a CVD system, a cooling and collection system, and a pneumatic conveying system. The feeder is connected to the ultrasonic atomization system. The pneumatic conveying system delivers gaseous precursors to the CVD system. The ultrasonic atomization system is configured to atomize the metal raw material to form droplets. The CVD system is configured to allow the gaseous precursors to react on the surface of the atomized metal droplets to form coated metal droplets. The cooling and collection system is configured to condense the coated metal droplets to form a "metal-deposition layer" core-shell structure particle. This invention avoids introducing additional impurities and achieves uniform coating of the shell material. It is suitable for both high-melting-point and low-melting-point metals, with a wide range of applications.

Description

Technical Field

[0001] This utility model relates to the field of vapor deposition technology, and in particular to an integrated ultrasonic atomization-chemical vapor deposition preparation device. Background Technology

[0002] Fluidized bed chemical vapor deposition (CVD) is a highly efficient powder surface modification technology. Its basic principle is to fluidize and suspend powder particles within a reaction chamber, ensuring sufficient and uniform contact between the reactant gases and the particle surface to facilitate a chemical reaction. This ultimately forms a dense and uniform coating layer on the surface of each individual particle. Due to its excellent coating effect, this technology has wide applications in high-end materials fields such as surface modification of lithium-ion battery electrode materials and catalyst preparation.

[0003] However, traditional fluidized bed CVD technology faces a core challenge: to induce thermal decomposition or chemical reactions in gaseous precursors, the process typically needs to be carried out at high temperatures. The powder materials to be processed, especially micro / nano powders with high specific surface area and high surface energy, are highly susceptible to sintering or agglomeration at high temperatures. Typically, the initial sintering temperature of a material is approximately 30%-50% of its melting point. For low-melting-point materials, the sintering temperature threshold is even lower, and sintering is highly likely to occur at conventional CVD process temperatures. Once the processing temperature exceeds the material's melting point, the powder will melt into droplets, leading to particle aggregation and fusion, resulting in a decline in product quality.

[0004] Existing technologies for addressing powder sintering primarily employ a "spatial isolation" strategy. This involves pre-dispersing powder particles before the reaction and dynamically maintaining their dispersion during fluidization to prevent direct contact between particles. Common dispersion and feeding methods include mechanical vibratory feeders and rotary scraper feeders. However, these mechanical dispersion methods have significant drawbacks: First, their dispersion force is coarse, making it difficult to achieve precise and uniform dispersion of powders, especially those prone to agglomeration, at the single-particle level. Second, during intense mechanical shaking or scraping, a large amount of unfixed powder material easily impacts and adheres to the inner wall of the reaction chamber. This not only results in significant waste of reaction materials and a substantial reduction in product yield but also leads to contamination and blockage of the reaction chamber, increasing equipment maintenance costs and production discontinuity.

[0005] Therefore, in view of the problems of uneven dispersion and chamber adhesion in the existing fluidized bed CVD technology when processing low melting point and easily sintered powder materials, there is an urgent need in this field to develop an integrated ultrasonic atomization-chemical vapor deposition device that can achieve efficient, mild and uniform dispersion of powder and can be seamlessly integrated with the CVD process. Utility Model Content

[0006] This utility model aims to solve the above-mentioned technical problems, namely, to solve the following problems existing in the mechanical dispersion method in the prior art: First, the dispersion force is coarse, making it difficult to achieve precise and uniform dispersion of powder, especially powder that is prone to agglomeration, at the single particle level; Second, during the violent mechanical shaking or scraping process, a large amount of unfixed powder material is very easy to impact and adhere to the inner wall of the reaction chamber. This not only causes serious waste of reaction raw materials and greatly reduces product yield, but also leads to pollution and blockage of the reaction chamber, increasing equipment maintenance costs and production discontinuity.

[0007] To this end, the present invention provides an integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation apparatus, comprising a feeder, an ultrasonic atomization system, a CVD system, a cooling and collection system, and a pneumatic conveying system. The feeder is connected to the ultrasonic atomization system for feeding metal raw materials into the ultrasonic atomization system. The ultrasonic atomization system, the CVD system, and the cooling and collection system are connected sequentially. The pneumatic conveying system is used to feed gaseous precursors into the CVD system for forming a shell material. The ultrasonic atomization system is configured to disperse and transport the atomized metal raw materials into droplets. The CVD system is configured to enable the gaseous precursors to undergo a CVD reaction on the surface of the atomized metal droplets to form core-shell coated metal droplets. The cooling and collection system is configured to condense the coated metal droplets to form core-shell structured particles of a "metal-deposition layer" and collect them.

[0008] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, the ultrasonic atomization system includes an ultrasonic cavity, an ultrasonic atomizer, and a material transfer mechanism. The feeder is installed at the top of the ultrasonic cavity, and the bottom of the ultrasonic cavity is connected to the chemical vapor deposition system. The material transfer mechanism is installed on the ultrasonic cavity, and the ultrasonic atomizer is located below the material transfer mechanism. The material transfer mechanism is configured to heat the metal raw material to form a liquid state and transport it to the ultrasonic atomizer. The ultrasonic atomizer is configured to ultrasonically atomize the transported liquid metal raw material to form droplet-shaped metal atomized droplets.

[0009] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, the material transfer mechanism includes a heating container, a discharge driver, and a transfer funnel. The top of the heating container is open. The heating container is disposed in the ultrasonic cavity and located directly below the feeder for holding and heating metal raw materials. The discharge driver is installed on the outer wall of the ultrasonic cavity and extends into the ultrasonic cavity to connect with the heating container. The transfer funnel is installed on the inner wall of the ultrasonic cavity and located between the heating container and the ultrasonic atomizer. A first heater is installed on the outer wall of the transfer funnel. The discharge driver is configured to drive the heating container to rotate at an angle to pour the liquid metal raw material into the transfer funnel. The metal raw material in the transfer funnel can fall onto the ultrasonic atomizer along the outlet of the transfer funnel.

[0010] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, the ultrasonic atomizer is a contact ultrasonic atomizer, which includes an ultrasonic generator, an ultrasonic transducer, and an atomizing head. The ultrasonic generator is installed on the outside of the ultrasonic cavity, and the ultrasonic generator is connected to the atomizing head through the ultrasonic transducer. The atomizing head extends into the ultrasonic cavity and is equipped with a third heater. The part of the atomizing head without the third heater is located directly below the transfer funnel in the ultrasonic cavity.

[0011] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, the chemical vapor deposition system includes a reaction pipeline and a second heater. The reaction pipeline is located between and connected to the ultrasonic atomization system and the cooling and collection system, and the second heater is sleeved on the reaction pipeline.

[0012] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, the ultrasonic atomization system, the chemical vapor deposition system, and the cooling and collection system are arranged sequentially from top to bottom in the height direction. The gas delivery system includes an inner delivery pipe, which is connected between the reaction pipe and the cooling and collection system. An outer shell is fixedly fitted on the outside of the inner delivery pipe, and two independent and vertically distributed annular channels are formed between the outer shell and the inner delivery pipe. Multiple circumferentially evenly distributed air outlets are provided on the inner wall of the inner delivery pipe at the location corresponding to each annular channel. An air inlet is provided on the outer wall of each annular channel for introducing gaseous precursors.

[0013] In a specific embodiment of the above-mentioned ultrasonic atomization-chemical vapor deposition integrated preparation device, the gas delivery system further includes a gas preheating device, which is located on one side of the internal delivery pipeline. One of the gas inlets is connected to the gas preheating outlet of the gas preheating device, and the other gas inlet and the gas preheating inlet on the gas preheating device are respectively used to introduce gaseous precursors of different compositions.

[0014] In a specific embodiment of the above-mentioned ultrasonic atomization-chemical vapor deposition integrated preparation device, the cooling collection system includes a receiving tank, a connecting flange, and a butterfly valve. The receiving tank is located directly below the internal conveying pipeline. The top of the receiving tank has an open structure, and the connecting flange is detachably connected to the top of the receiving tank. The top of the connecting flange is fixedly connected to the internal conveying pipeline through the butterfly valve. The outer wall of the receiving tank has a double-layer hollow structure for connecting to the first cooling system to introduce the cooling medium.

[0015] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, an anti-melting channel is installed between the feeder and the ultrasonic atomization system, and a second cooling system is connected to the outer wall of the anti-melting channel.

[0016] In a specific embodiment of the above-mentioned integrated ultrasonic atomization-chemical vapor deposition preparation device, an exhaust port is provided at the top of the ultrasonic cavity, a vacuum pump is installed on the exhaust port, and a third cooling system is connected to the outside of the ultrasonic cavity for cooling the ultrasonic cavity; and / or A connecting channel is installed between the outlet of the ultrasonic atomization system and the inlet of the chemical vapor deposition system, and a vacuum valve is installed on the outer peripheral wall of the connecting channel.

[0017] Compared with the prior art, the beneficial effects of this utility model are: 1. This invention melts non-liquid metal raw materials into a liquid state, then uses an ultrasonic atomizer to ultrasonically atomize the liquid metal raw materials to break them into small droplets. The gaseous precursor undergoes a chemical vapor deposition reaction on the surface of the suspended, flowing metal atomized droplets to form core-shell coated metal droplets. Finally, after cooling, the coated metal droplets solidify to form "metal-deposition layer" core-shell structure particles for collection. This process eliminates the need for introducing additional impurities (isolation particles), ensuring the fluidity of the gas flow. Furthermore, the breaking into small droplets provides a more uniform and sufficient mass transfer effect for the reacting gas, enabling uniform coating of the shell material. Because the preparation device designed in this invention operates while the metal raw materials are melted into a liquid state, it is applicable to both high-melting-point and low-melting-point metal raw materials, offering a wide range of applications and solving the problems of sintering or agglomeration that occur during chemical vapor deposition reactions.

[0018] 2. Compared with the direct powder dispersion method, the ultrasonic atomization into small droplets achieves more complete dispersion and a lower probability of collision sintering. This avoids the problem that a large amount of unfixed powder material is easily impacted and adhered to the inner wall of the reaction chamber during violent mechanical shaking or scraping. At the same time, the metal raw material in the preparation device designed by this invention is atomized in a liquid state. It is not limited to using raw materials in powder form, nor is it restricted by the original particle size distribution of the powder raw material. Under certain process parameters, powder with uniform particle size can be obtained, which solves the problem that the product size and reaction effect are uncontrollable due to sintering and agglomeration caused by the contact between particles.

[0019] 3. This utility model has heaters installed on both the transfer funnel and the ultrasonic atomizer for preheating, which prevents molten metal raw materials from entering the transfer funnel and atomizing head from cooling and adhering to them due to low temperature, thus helping to improve the fluidity of the metal raw materials and the atomization effect. Attached Figure Description

[0020] The preferred embodiments of this utility model are described below with reference to the accompanying drawings, in which: Figure 1 This is a front view of the integrated ultrasonic atomization-chemical vapor deposition preparation device provided by this utility model; Figure 2 yes Figure 1 Enlarged view of the ultrasonic atomization system, connecting channel, and the connection between the two; Figure 3 yes Figure 1 Internal structure diagram of the ultrasonic atomization system Figure 4 yes Figure 2 Enlarged view of the connection between the central connecting channel and the first cooling jacket; Figure 5 yes Figure 1 Enlarged structural diagram of the connection between the chemical gas phase reaction system, gas delivery system, and cooling and collection system; Figure 6 yes Figure 5 Enlarged structural diagram of the central airflow delivery system and cooling collection system; Figure 7 yes Figure 6 A schematic diagram of the structure forming an annular channel between the internal pipeline and the outer shell; Figure 8 This is a photograph of indium powder coated with graphene prepared using the preparation device designed in this invention. Figure 9 This is a physical image of indium powder coated with graphene, obtained by directly dispersing powder in existing technologies.

[0021] List of reference numerals in the attached diagram: 1. Ultrasonic atomization system; 101. Ultrasonic cavity; 102. Ultrasonic atomizer; 1021. Atomizing head; 103. Discharge driver; 1031. Pull rod; 1032. Fixing base; 1033. Drive shaft; 104. Heating container; 105. Transfer funnel; 2. Chemical vapor deposition system; 201. Second heater; 202. Reaction pipeline; 3. Pneumatic conveying system; 301. Outer shell; 302. Internal pipeline; 3021. Outlet... 303. Vent; 4. Annular channel; 5. Cooling collection system; 6. Collection tank; 7. Connecting flange; 8. Butterfly valve; 9. Feeder; 10. Anti-melting channel; 11. Connecting channel; 12. Exhaust port; 13. Air inlet; 14. First cooling jacket; 15. Vacuum valve; 16. Second cooling jacket; 17. Third heater; 18. Control cabinet; 19. Human-machine interface device; 10. Gas preheating device; 11. Support frame; 12. Support leg. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the scope of protection of this utility model.

[0023] In the description of this utility model, it should be noted that the terms "upper," "lower," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the system or component referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the use of terms such as "first" and "second" to define components is merely for the convenience of distinguishing the aforementioned components. Unless otherwise stated, these terms have no special meaning and should not be construed as indicating or implying relative importance.

[0024] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "setting," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0025] This utility model relates to the field of vapor deposition technology, and in particular to an integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation apparatus for preparing particles with a metal core and a CVD shell structure. The aim is to solve the following technical problems: First, the dispersion is coarse, making it difficult to achieve precise and uniform dispersion of powders, especially those prone to agglomeration, at the single-particle level; second, during intense mechanical shaking or scraping, a large amount of unfixed powder material easily impacts and adheres to the inner wall of the reaction chamber, which not only causes serious waste of reaction materials and significantly reduces product yield, but also leads to contamination and blockage of the reaction chamber, increasing equipment maintenance costs and production discontinuity. Therefore, the integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation apparatus provided by this utility model solves the above problems.

[0026] The ultrasonic atomization-chemical vapor deposition integrated preparation apparatus provided in the embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0027] See Figure 1-6 This invention provides an integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation device, comprising a feeder 5, an ultrasonic atomization system 1, a CVD system 2, a cooling and collection system 4, and a pneumatic conveying system 3. The feeder 5 is connected to the ultrasonic atomization system 1 to feed metal raw materials into the ultrasonic atomization system 1. The ultrasonic atomization system 1, the CVD system 2, and the cooling and collection system 4 are connected in sequence. The pneumatic conveying system 3 is used to feed gaseous precursors into the CVD system 2 to form a shell material. The ultrasonic atomization system 1 is configured to atomize the metal raw materials to form droplets for dispersion and transport, i.e., to form metal atomized droplets. The CVD system 2 is configured to enable the gaseous precursors to undergo a chemical vapor deposition reaction on the surface of the metal atomized droplets to form a shell material, thereby forming a core-shell structured coated metal droplet. The cooling and collection system 4 is configured to condense the coated metal droplets to form a "metal-deposition layer" core-shell structured particle and collect it.

[0028] In the above embodiments, preferably, see [reference needed]. Figure 2-3 The ultrasonic atomization system 1 includes an ultrasonic cavity 101, an ultrasonic atomizer 102, and a material transfer mechanism. A feeder 5 is installed at the top of the ultrasonic cavity 101, and the bottom of the ultrasonic cavity 101 is connected to the chemical vapor deposition system 2. The material transfer mechanism is installed on the ultrasonic cavity 101, and the ultrasonic atomizer 102 is located below it. The material transfer mechanism is configured to heat the metal raw material to form a liquid state and transport it to the ultrasonic atomizer 102. The ultrasonic atomizer 102 is configured to ultrasonically atomize the transported liquid metal raw material to form droplet-shaped metal atomized droplets. An observation window is provided on the ultrasonic cavity.

[0029] In the above embodiment, an exhaust port 8 is provided at the top of the ultrasonic cavity 101, and a vacuum pump is installed on the exhaust port 8. A third cooling system is connected to the outside of the ultrasonic cavity 101 for cooling the ultrasonic cavity 101. For example, a water-cooling system is used for the third cooling system, and water is the circulating cooling medium. Specifically, the outer wall of the ultrasonic cavity 101 is designed as a double-layer wall, with a cavity formed between the two layers for the cooling medium to pass through. Circulating cold water is introduced into the cavity through the water-cooling system to prevent the ultrasonic cavity 101 from being damaged prematurely due to high temperature. A pressure sensor is also installed on the ultrasonic cavity 101 to detect the internal pressure.

[0030] In one embodiment, see Figure 3 The ultrasonic nebulizer 102 is a contact-type ultrasonic nebulizer 102, which includes an ultrasonic generator, an ultrasonic transducer, and an atomizing head 1021. The ultrasonic generator is installed on the outside of the ultrasonic cavity 101, but not directly fixed to it. The ultrasonic generator is connected to the atomizing head 1021 through the ultrasonic transducer. The atomizing head 1021 extends into the ultrasonic cavity and is equipped with a third heater 13. The part of the atomizing head 1021 without the third heater 13 is located directly below the transfer funnel 105 inside the ultrasonic cavity 101. The droplet size is controlled by the ultrasonic processing rate, ultrasonic amplitude, ultrasonic frequency, and heating parameters.

[0031] In the above embodiments, preferably, see [reference needed]. Figure 3 The material transfer mechanism includes a heating container 104, a discharge driver 103, and a transfer funnel 105. The top of the heating container 104 is open. The heating container 104 is located inside the ultrasonic cavity 101 and directly below the feeder 5. It is used to hold and heat the metal raw material. The discharge driver 103 is installed on the outer wall of the ultrasonic cavity 101 and extends into the ultrasonic cavity 101 to connect with the heating container 104. The transfer funnel 105 is installed on the inner wall of the ultrasonic cavity 101 and is located between the heating container 104 and the ultrasonic atomizer 102. A first heater is installed on the outer wall of the transfer funnel 105. The discharge driver 103 is configured to drive the heating container 104 to rotate at an angle to pour the liquid metal raw material into the transfer funnel 105. The liquid metal raw material in the transfer funnel 105 can fall onto the ultrasonic atomizer 102 along the outlet of the transfer funnel 105.

[0032] Specifically, the opening of the heating container 104 corresponds precisely to the feeder 5. This allows the metal raw material, after being fed into the ultrasonic cavity 101 via the feeder 5, to fall directly into the heating container 104 for heating. When the metal raw material is not liquid, it needs to be heated to a molten state for ultrasonic atomization in a liquid state, forming atomized metal droplets. All circuits inside the ultrasonic cavity 101 are introduced into the cavity using ceramic terminal flanges to ensure airtightness. This method is existing technology and will not be described in detail. The heating method of the heating container 104 includes, but is not limited to, resistance heating and induction heating. The heating container 104 can be selected depending on the material, such as a graphite crucible.

[0033] In the above embodiment, the liquid falling from the outlet of the transfer funnel 105 is directly dripped onto the atomizing head and ultrasonically vibrated to break it up into metal atomized droplets. The outlet aperture of the transfer funnel 105 is set according to the amount of liquid that the ultrasonic atomizer 102 can continuously and stably atomize, and is not specifically limited in this application.

[0034] In the above embodiments, a first heater is provided on the outside of the transfer funnel 105, and a third heater 13 is installed on the atomizing head to preheat the transfer funnel 105 and the atomizing head, preventing the molten metal raw material from solidifying on the transfer funnel 105 and the atomizing head. The heating methods of the first heater and the third heater 13 can be electric heating or induction heating, which can be flexibly selected according to specific circumstances.

[0035] In this application, the unloading driver 103 can be electrically driven, such as by a motor and a reducer. It can also be manually driven. For example, see [reference needed]. Figure 3The unloading driver 103 includes a pull rod 1031, a drive shaft 1033, and a fixed seat 1032. The fixed seat 1032 is fixed to the outside of the ultrasonic cavity 101. The drive shaft 1033 is installed in the fixed seat 1032 and rotatably connected to it. One end of the drive shaft 1033 passes through the fixed seat 1032 and extends into the ultrasonic cavity 101 to be fixedly connected to the heating container 104. The top of the fixed seat 1032 has an arc-shaped notch. The bottom end of the pull rod 1031 passes through the notch to be fixedly connected to the drive shaft 1033 so that the drive shaft 1033 is driven by the pull rod 1031 to drive the heating container 104 to rotate at an angle. When the pull rod 1031 is engaged with one end of the arc-shaped notch to reach the limit of its movement trajectory, the heating container 104 is in an upright position, i.e., the opening of the heating container 104 is facing upwards. When the pull rod 1031 is engaged with the other end of the arc-shaped notch to reach the limit of its movement trajectory, the heating container 104 is flipped to an inclined position to pour the molten metal material into the transfer funnel 105. One end of the fixed seat 1032 extends into the ultrasonic cavity 101. The drive shaft 1033 and the fixed seat 1032 are rotatably connected by a bearing. To ensure the sealing of the ultrasonic cavity 101, an oil seal is used for sealing. Because the oil seal provides resistance to the rotation of the drive shaft 1033, the heating container 104 will not swing arbitrarily when it is in an upright position. Of course, to be on the safe side, a first pin hole can be made on the fixed seat, and a second pin hole can be made on the shaft in the aligned position at the position corresponding to the first pin hole. The pin can be inserted into the first pin hole and the second pin hole to limit the rotation of the shaft.

[0036] In the above embodiments, preferably, see [reference needed]. Figure 5 The chemical vapor deposition system 2 includes a reaction pipe 202 and a second heater 201. The reaction pipe 202 is located between and connected to the ultrasonic atomization system 1 and the cooling collection system 4. The second heater 201 is mounted on the reaction pipe 202.

[0037] In the above embodiments, preferably, the ultrasonic atomization system 1, the chemical vapor deposition system 2, and the cooling and collection system 4 are arranged sequentially from top to bottom along the height direction, i.e., installed vertically. In this manner, the atomized metal droplets enter the chemical vapor deposition system 2 and the cooling and collection system 4 sequentially under their own gravity. Exemplarily, the second heater 201 is a heating furnace structure, and the reaction pipe 202 passes through the furnace space of the heating furnace for heating.

[0038] The temperature and type of reaction gas flow within reaction pipe 202 are determined according to the requirements of the chemical vapor deposition reaction. The composition of the reaction gas flow may include, but is not limited to, hydrogen, oxygen, methane, acetylene, ethylene, ammonia, hexacycloborane vapor, methanol vapor, sulfur vapor, etc. The carrier gas can be an inert gas such as helium, argon, or nitrogen. The content of these gases can be controlled by a flow meter, and preheating and premixing can be performed as needed for the reaction.

[0039] In the above embodiments, preferably, see [reference needed]. Figure 6-7 The pneumatic conveying system 3 includes an internal conveying pipe 302, which is connected between the reaction pipe 202 and the cooling collection system 4. An outer shell 301 is fixedly fitted on the outside of the internal conveying pipe 302. Two independent and vertically distributed annular channels 303 are formed between the outer shell 301 and the internal conveying pipe 302. Multiple circumferentially evenly distributed air outlets 3021 are provided on the inner wall of the internal conveying pipe 302 at the corresponding part of each annular channel 303. An air inlet 9 is provided on the outer wall of each annular channel 303 for introducing gaseous precursor.

[0040] In the above embodiments, preferably, the pneumatic conveying system 3 further includes a gas preheating device 16, which is located on one side of the internal conveying pipeline 302. One of the air inlets 9 is connected to the gas preheating outlet of the gas preheating device 16, and the other air inlet 9 and the gas preheating inlet on the gas preheating device 16 are respectively used to introduce gaseous precursors of different compositions.

[0041] Exemplarily, the gas preheating device 16 includes a preheating chamber, a serpentine stainless steel pipe, and a fourth heater. Both the fourth heater and the serpentine stainless steel pipe are disposed within the preheating chamber, with the serpentine stainless steel pipe coiled around the fourth heater. The preheating chamber has a gas preheating outlet and a gas preheating inlet communicating with the serpentine stainless steel pipe. Another air inlet 9 and the gas preheating inlet on the gas preheating device 16 are respectively connected to a delivery pipeline. The delivery pipeline is used to connect to a gas source, and a flow meter and a pressure detector are installed on the delivery pipeline. The flow meter is used to measure the flow rate of the gaseous precursor.

[0042] In the above embodiments, for gaseous precursors of different compositions, some can be preheated, such as argon; while others are not easily preheated, such as flammable and explosive gases like hydrogen and acetylene. Two independent annular channels 303 are formed between the outer shell 301 and the inner delivery pipe 302. One annular channel 303 can be used to introduce preheated gaseous precursors, while the other annular channel 303 allows gaseous precursors that do not require preheating (i.e., at room temperature) to pass through. This facilitates the separation of gaseous precursors requiring and not requiring preheating from different compositions, which not only helps improve reaction efficiency but also ensures safety. Simultaneously, multiple vent holes 3021 are provided on the inner wall of the inner delivery pipe 302, allowing the gas in each annular channel 303 to diffuse into the inner delivery pipe 302, which helps to make the gas flow more uniformly mixed.

[0043] In the above embodiments, preferably, see [reference needed]. Figure 6 The cooling collection system 4 includes a receiving tank 401, a connecting flange 402, and a butterfly valve 403. The receiving tank 401 is located directly below the internal conveying pipe 302. The top of the receiving tank 401 is an open structure. The top of the receiving tank 401 is detachably connected to the connecting flange 402. The top of the connecting flange 402 is fixedly connected to the internal conveying pipe 302 through the butterfly valve 403. The outer wall of the receiving tank 401 is a double-layer hollow structure used to connect to the first cooling system to introduce the cooling medium.

[0044] This application does not specifically limit the first cooling system. Exemplarily, the first cooling system is a liquid nitrogen cooling system, with liquid nitrogen as the cooling medium. An inlet and an outlet are respectively provided on the outer wall of the receiving tank 401. Liquid nitrogen enters the hollow structure through the inlet and exits through the outlet. The liquid nitrogen cools the coated metal droplets inside the receiving tank 401, forming core-shell structure particles of a "metal-deposited layer" that accumulate within the receiving tank 401, thus achieving the collection function. At least two evenly distributed handles are fixed to the outer wall of the receiving tank 401 to facilitate handling of the receiving tank 401.

[0045] More specifically, the top edge of the receiving tank 401 extends outward to form a flange, which is detachably fixed to the connecting flange 402 by bolts. When it is necessary to remove the material from the receiving tank 401, the butterfly valve 403 is closed to isolate the internal conveying pipe 302 in the pneumatic conveying system 3 from the receiving tank 401. Then, the bolts are removed, and the receiving tank 401 is detached from the connecting flange 402, allowing the collected material to be removed.

[0046] In the above embodiments, preferably, see [reference needed]. Figure 2A melt-proof channel 6 is installed between the feeder 5 and the ultrasonic atomization system 1, and a second cooling system is connected to the outer wall of the melt-proof channel 6. The second cooling system is exemplarily a water-cooling system, which includes a second cooling jacket 12 installed outside the melt-proof channel 6. Circulating cold water can be introduced into the second cooling jacket 12 through the water-cooling system, thus preventing the hot gas blown up from the chemical vapor deposition system 2 from melting the material. This invention melts non-liquid metal raw materials into a liquid state, then uses an ultrasonic atomizer 102 to ultrasonically atomize the liquid metal raw materials, breaking them into metal droplets. The gaseous precursor undergoes a chemical vapor deposition reaction on the surface of the suspended, flowing metal droplets to form coated metal droplets. Finally, the coated metal droplets are cooled and collected by a cooling and collection system 4 to form core-shell structured particles of "metal-deposition layer." This process avoids the introduction of additional impurities, and the breakup into droplets provides a more uniform and sufficient mass transfer effect for the reacting gas, achieving uniform coating. It is applicable to both high-melting-point and low-melting-point raw materials, broadening its application range. Compared to direct powder dispersion, ultrasonic atomization into small droplets achieves more complete dispersion and a lower probability of collision sintering. Furthermore, this invention is not limited to powder-like raw materials and is not constrained by the original particle size distribution of the powder raw material; under defined process parameters, powders with uniform particle size can be obtained.

[0047] In this application, the feeder 5 is exemplarily described as follows: the feeder 5 includes a feed hopper, a sealing cover, and a rotary scraper. The top of the feed hopper is detachably connected to the sealing cover, and the bottom of the feed hopper is fixedly connected to the top of the anti-melting channel 6. A drive shaft is installed at the top of the sealing cover, and the drive shaft passes through the sealing cover. A hand crank is installed at the top of the drive shaft, and an internal spline groove is provided at the bottom of the drive shaft. A material support plate is fixed inside the feed hopper, and a feed inlet is provided on the material support plate to communicate with the feed hopper below. The rotary scraper includes a rotating shaft and scrapers. The bottom of the rotating shaft is rotatably connected to the material support plate, and at least two circumferentially distributed scrapers are fixed on the rotating shaft. The scrapers, the material support plate, and the inner sidewall of the feed hopper combine to form a receiving cavity for receiving metal raw materials. A spline shaft that matches the internal spline groove is fixed at the top of the rotating shaft. The matching of the spline shaft and the internal spline groove enables the drive shaft to drive the rotating shaft to rotate, while not hindering the disassembly and installation of the sealing cover. The scraper is driven to rotate by the rotating shaft to transport the metal raw material to the feed inlet and into the feed hopper below the material support plate. The raw material is then discharged through the bottom of the feed hopper into the inner hole of the anti-melting channel 6 and then into the ultrasonic atomization system 1.

[0048] In the above embodiments, preferably, see [reference needed]. Figure 2 and Figure 4The integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation apparatus also includes a connecting channel 7, which connects the outlet of the ultrasonic atomization system 1 and the inlet of the CVD system 2. A fourth cooling system is connected to each connection point for cooling. A vacuum valve 11 is installed on the outer peripheral wall of the connecting channel 7. In the case of vertical installation, the top end of the reaction pipe 202 is connected to the bottom end of the connecting channel 7, and the bottom end of the reaction pipe 202 is connected to the top end of the internal conveying pipe 302 described below.

[0049] Specifically, the top and bottom of the connecting channel 7 both extend outwards with a first flange, the bottom of the ultrasonic cavity 101 is fixed with a second flange, and the top of the reaction pipe 202 in the chemical vapor deposition system 2 is fixed with a third flange. The first flange at the top of the connecting channel 7 is detachably and fixedly connected to the second flange, and the first flange at the bottom of the connecting channel 7 is detachably and fixedly connected to the third flange. The connecting channel 7 also has a spare interface for installing pressure detectors, etc.

[0050] A fourth cooling system is used to cool the connection parts. This application does not specifically limit the fourth cooling system. Exemplarily, a water-cooling system is used. The fourth cooling system includes a first cooling jacket 10. When using a water-cooling system, the circulating cooling medium is circulating cold water. To ensure sealing, sealing rings are installed at the connection points of adjacent flanges. A first cooling jacket 10 is installed on the outer peripheral wall of the connection channel 7 near the first flange at the top, the bottom of the connection channel 7 near the first flange at the bottom, and the outer peripheral wall of the reaction pipe 202 near the third flange at the top. Circulating cold water is circulated through the first cooling jacket 10 by the water-cooling system to cool the sealing rings and prevent premature damage to the sealing rings due to high temperatures, thus affecting the sealing performance.

[0051] See Figure 1The integrated ultrasonic atomization-chemical vapor deposition (CVD) preparation apparatus designed in this application also includes a support frame 17, a control system, a pressure detection system, and a gas supply delivery system. The ultrasonic cavity 101, the connecting channel 7, and the second heater 201 are all mounted on the support frame 17, and the receiving tank 401 is placed below the reaction channel. Exemplarily, at least three evenly distributed support legs 18 are fixed to the outer wall of the ultrasonic cavity 101. The support legs 18 are mounted on the top of the support frame 17 to support the ultrasonic cavity 101. The ultrasonic atomizer is mounted on the support frame or the support legs. The connecting channel 7 and the second heater 201 are both mounted on the support frame 17. A control cabinet 14 and a human-machine interface device 15 are mounted on the support frame 17 on one side of the ultrasonic cavity 101. The control system is installed inside the control cabinet 14. The human-machine interface device 15, the heating container 104, the first heater, the third heater 13, the fourth heater, the vacuum pump, the flow meter, and the pressure detection system are connected to the control system for controlling parameters such as temperature, pressure, flow rate, and vacuum. The pressure detection system includes multiple pressure detectors, which can be pressure sensors, used to detect the pressure in required locations, such as the pressure inside the ultrasonic cavity 101 and the pressure in the gas delivery pipeline. It should be noted that controlling parameters such as the gas flow rate, cavity pressure, and various heating temperatures through a control system is known to those skilled in the art, and therefore will not be described in detail. To ensure heating accuracy, the second heater 201 has its own control system. Furthermore, this application does not specifically limit the specific structure of the support frame 17; it can be flexibly set according to actual conditions.

[0052] The following example illustrates the working process using a vertical installation of the ultrasonic atomization system 1, chemical vapor deposition system 2, and cooling collection system 4.

[0053] When the metal raw material is a powder, it is added to the heating container 104 through the feeder 5. The heating container 104 heats the metal raw material to a molten state. The molten metal raw material is then discharged into the transfer hopper by the discharge driver 103, which flips the heating container 104. The molten metal raw material then drips onto the atomizing head 1021 of the ultrasonic atomizer 102 through the outlet of the transfer hopper to form metal atomized droplets. The metal atomized droplets fall downwards under their own gravity. During this process, the gaseous precursor is transported to the internal conveying pipe 302 through the airflow conveying system 3. Then, it enters the reaction pipe 202 and undergoes chemical vapor deposition on the surface of the metal atomized droplets to form coated metal droplets. The droplets then continue to fall and enter the receiving tank 401 through the internal conveying pipe 302. After being cooled by the first cooling system, the core-shell structure particles of the "metal-deposition layer" are collected in the receiving tank 401. The airflow in the upward-moving ultrasonic cavity is discharged through the exhaust port 8.

[0054] See Figure 8-9 , Figure 8 This is a physical image of indium powder coated with graphene prepared using the preparation device designed in this utility model. The reaction temperature during chemical vapor deposition is 1380℃, and 4800 sccm of argon, 1000 sccm of hydrogen, 200 sccm of 5% acetylene diluted with argon, and 100 sccm of 2‰ oxygen diluted with argon are continuously introduced into the chemical vapor deposition reaction zone, while the pressure is controlled at a constant pressure of 95 kPa. Figure 9 This is a photograph of indium powder coated with graphene, obtained by directly dispersing powder in existing technologies. From... Figure 8 It can be seen from this that the powder particles are small in size and do not agglomerate, while from Figure 9 Agglomeration and clumping can occur, resulting in large powder sizes. Therefore, this invention solves the problem that in the high-temperature chemical vapor deposition (CVD) process of some metal raw materials, sintering and agglomeration occur due to interparticle contact, leading to uncontrollable product size and reaction efficiency.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the protection scope of the technical solutions of the embodiments of this utility model.

Claims

1. An integrated ultrasonic atomization-chemical vapor deposition preparation device, characterized in that, The system includes a feeder, an ultrasonic atomization system, a chemical vapor deposition system, a cooling and collection system, and a pneumatic conveying system. The feeder is connected to the ultrasonic atomization system to deliver metal raw materials to the ultrasonic atomization system. The ultrasonic atomization system, the chemical vapor deposition system, and the cooling and collection system are connected in sequence. The pneumatic conveying system delivers gaseous precursors to the chemical vapor deposition system to form a shell material. The ultrasonic atomization system is configured to atomize the metal raw materials to form droplets for dispersion and transport. The chemical vapor deposition system is configured to enable the gaseous precursors to undergo a chemical vapor deposition reaction on the surface of the atomized metal droplets to form coated metal droplets with a core-shell structure. The cooling and collection system is configured to condense the coated metal droplets to form "metal-deposition layer" core-shell structured particles and collect them.

2. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 1, characterized in that, The ultrasonic atomization system includes an ultrasonic cavity, an ultrasonic atomizer, and a material transfer mechanism. The feeder is installed at the top of the ultrasonic cavity, and the bottom of the ultrasonic cavity is connected to the chemical vapor deposition system. The material transfer mechanism is installed on the ultrasonic cavity, and the ultrasonic atomizer is located below the material transfer mechanism. The material transfer mechanism is configured to heat the metal raw material to form a liquid state and transport it to the ultrasonic atomizer. The ultrasonic atomizer is configured to ultrasonically atomize the transported liquid metal raw material to form droplet-shaped metal atomized droplets.

3. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 2, characterized in that, The material transfer mechanism includes a heating container, a discharge driver, and a transfer funnel. The heating container has an open top and is located inside the ultrasonic cavity, directly below the feeder, for holding and heating the metal raw material. The discharge driver is mounted on the outer wall of the ultrasonic cavity and extends into the ultrasonic cavity to connect with the heating container. The transfer funnel is mounted on the inner wall of the ultrasonic cavity and located between the heating container and the ultrasonic atomizer. A first heater is installed on the outer wall of the transfer funnel. The discharge driver is configured to cause the heating container to rotate at an angle to pour the liquid metal raw material into the transfer funnel. The metal raw material in the transfer funnel can fall onto the ultrasonic atomizer along the outlet of the transfer funnel.

4. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 3, characterized in that, The ultrasonic nebulizer is a contact ultrasonic nebulizer, which includes an ultrasonic generator, an ultrasonic transducer, and a nebulizing head. The ultrasonic generator is installed on the outside of the ultrasonic cavity and is connected to the nebulizing head through the ultrasonic transducer. The nebulizing head extends into the ultrasonic cavity and is equipped with a third heater. The part of the nebulizing head without the third heater is located directly below the transmission funnel inside the ultrasonic cavity.

5. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 1, characterized in that, The chemical vapor deposition system includes a reaction conduit and a second heater. The reaction conduit is located between and connected to the ultrasonic atomization system and the cooling collection system. The second heater is mounted on the reaction conduit.

6. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 5, characterized in that, The ultrasonic atomization system, chemical vapor deposition system, and cooling collection system are arranged sequentially from top to bottom along the height direction. The pneumatic delivery system includes an inner delivery pipe, which is connected between the reaction pipe and the cooling collection system. An outer shell is fixedly fitted around the outer side of the inner delivery pipe, forming two independent and vertically distributed annular channels between the outer shell and the inner delivery pipe. Multiple circumferentially evenly distributed air outlets are provided on the inner wall of the inner delivery pipe at locations corresponding to each annular channel. An air inlet is provided on the outer wall of each annular channel for introducing gaseous precursors.

7. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 6, characterized in that, The pneumatic conveying system also includes a gas preheating device, which is located on one side of the internal conveying pipeline. One of the gas inlets is connected to the gas preheating outlet of the gas preheating device, and the other gas inlet and the gas preheating inlet on the gas preheating device are used to introduce gaseous precursors of different compositions.

8. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 6, characterized in that, The cooling collection system includes a receiving tank, a connecting flange, and a butterfly valve. The receiving tank is located directly below the internal conveying pipeline. The top of the receiving tank has an open structure, and the connecting flange is detachably connected to the top of the receiving tank. The top of the connecting flange is fixedly connected to the internal conveying pipeline through the butterfly valve. The outer wall of the receiving tank has a double-layer hollow structure for connecting to the first cooling system to allow the cooling medium to pass through.

9. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 1, characterized in that, An anti-melting channel is installed between the feeder and the ultrasonic atomization system, and a second cooling system is connected to the outer wall of the anti-melting channel.

10. The integrated ultrasonic atomization-chemical vapor deposition preparation apparatus according to claim 2, characterized in that, The ultrasonic cavity is provided with an exhaust port at its top, and a vacuum pump is installed on the exhaust port. A third cooling system is connected to the outside of the ultrasonic cavity for cooling the ultrasonic cavity; and / or A connecting channel is installed between the outlet of the ultrasonic atomization system and the inlet of the chemical vapor deposition system, and a vacuum valve is installed on the outer peripheral wall of the connecting channel.

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