High-entropy nano oxide nanowire preparation device and method based on ultrasonic micro pressure

Abstract

The device comprises a precursor solution storage tank, an injection pump, a reaction pipeline and a product collection and storage tank which are sequentially communicated, a first valve is arranged between the precursor solution storage tank and the injection pump, a plurality of one-way valves are arranged on the reaction pipeline, and a second valve is arranged on the product collection and storage tank. The reaction pipeline is arranged in the ultrasonic pool; the precursor solution storage tank is used for storing a prepared precursor solution; the injection pump is used for injecting the precursor solution from the precursor solution storage tank into the reaction pipeline; the reaction pipeline is used as a container for synthetic reaction; the one-way valve is used for ensuring that the solution is gradually input into the product collection and storage tank from the precursor solution storage tank in a one-way manner; and the ultrasonic pool is used for generating ultrasonic waves and performing temperature control. The device provided by the invention realizes continuous preparation of the one-dimensional oxide nanowire, and realizes preparation of the one-dimensional high-entropy oxide nanowire with uniformly distributed elements by a simple process and a precursor.

Description

Technical Field

[0001] This invention relates to the field of chemical synthesis technology of high-entropy oxides, specifically to a device and method for preparing high-entropy nano-oxide nanowires based on ultrasonic micro-pressure. Background Technology

[0002] High-entropy oxide nanowires (HEO NWs), as an emerging one-dimensional nanomaterial, are one-dimensional nanostructures composed of five or more metal cations and oxygen anions in equimolar or near-equimolar ratios. This multi-component composition endows them with unique high-entropy effects, lattice distortion effects, sluggish diffusion effects, and cocktail effects, distinguishing them from traditional binary or ternary oxide materials in terms of physical and chemical properties. They exhibit great potential in fields such as energy storage, catalysis, and materials for extreme environments.

[0003] High-entropy oxide nanowires possess entropy stabilization and functional tunability, excellent structural stability and environmental tolerance, superior mechanical properties, and high catalytic activity. Among these, the entropy increase effect overcomes the positive enthalpy of mixing between various elements, stabilizing the single-phase structure and suppressing phase separation. This allows multiple metal elements that are normally immiscible under conventional thermodynamic conditions to form a homogeneous solid solution at the atomic scale, significantly increasing the stability of high-entropy oxide nanowires. Furthermore, by changing the type and proportion of metal elements, the electrical, optical, and catalytic properties of the material can be precisely controlled. Benefiting from this core effect, high-entropy oxide nanowires possess several excellent functional properties, including: extreme temperature stability, exhibiting outstanding stability in high-temperature environments, with broad application prospects in fields such as thermal barrier coatings for aerospace engines and high-temperature sensors; high-pressure tolerance, with HEO nanowires also exhibiting remarkable stability under high pressure environments, showing great application potential in deep-sea exploration equipment and high-pressure reaction devices; chemical environment stability, with HEO nanowires able to withstand harsh chemical environments, showing potential for long-term service in corrosive environments in the chemical industry and electrolyte environments in electrochemical systems; excellent mechanical properties, including high hardness and elastic recovery, with great application prospects in the field of high-performance structural materials; and enhanced electrochemical performance, including excellent cycle stability, rate performance, and catalytic activity, exhibiting outstanding performance in battery and catalytic applications.

[0004] Although high-entropy oxide nanowires possess numerous superior properties, their synthesis technology still faces many challenges. Existing methods suffer from varying degrees of complexity, high cost, and insufficient control precision, severely limiting the large-scale production and practical application of HEO nanowires. High-temperature synthesis is the most traditional method for preparing high-entropy oxides, typically requiring solid-state reactions or melt crystallization at temperatures above 1000℃. However, due to the rapid crystal growth rate and random orientation at high temperatures, it is difficult to form uniform one-dimensional nanostructures. The resulting products are usually micron-sized particles rather than nanowires. Furthermore, because different metal elements have different diffusion rates and volatility, elemental segregation easily occurs during long-term high-temperature processing, leading to localized compositional inhomogeneity and phase separation, preventing the achievement of a truly entropy-stable state. High-temperature synthesis also consumes a lot of energy and requires demanding equipment, with extremely high temperature resistance requirements for the reaction vessel, increasing production costs and technical difficulty. Wet chemical methods (such as sol-gel and hydrothermal / solvothermal methods) can synthesize HEO nanowires at relatively low temperatures. However, achieving a uniform distribution of multiple metal elements requires careful design of the metal precursor ratios and hydrolysis kinetics. Any slight deviation can lead to compositional discrepancies and impurities in the target phase. Furthermore, at low temperatures, ion mobility is low, and the miscibility barriers between various metal elements are difficult to overcome, often necessitating subsequent high-temperature annealing. This, in turn, can cause the nanowires to sinter and grow, losing their nanoscale properties.

[0005] To address the aforementioned problems, this invention describes a wet chemical synthesis method for high-entropy oxide nanowires based on aqueous solutions. This method can synthesize one-dimensional high-entropy oxide nanowires with uniform mixing of various elements and no phase separation using simple metal salt precursors. Furthermore, by employing a continuous preparation device, the continuous preparation of one-dimensional high-entropy oxide nanowires can be achieved, laying the foundation for their large-scale production. Summary of the Invention

[0006] The purpose of this invention is to overcome the problems existing in the prior art and provide a device and method for preparing high-entropy oxide nanowires based on ultrasonic micro-pressure. It designs a "continuous precursor injection - micro-pressure ultrasonic reaction - product collection system" to realize the continuous preparation of one-dimensional oxide nanowires, solves the problems of high precursor requirements and easy phase separation in the wet chemical method for preparing high-entropy oxide nanowires, and achieves the preparation of one-dimensional high-entropy oxide nanowires with uniform element distribution with simple process and precursor.

[0007] To achieve the above-mentioned technical objectives and effects, the present invention is implemented through the following technical solution: A device for preparing high-entropy nano-oxide nanowires based on ultrasonic micro-pressure is disclosed. The device includes a reaction module comprising a precursor solution storage tank, an injection pump, a reaction pipeline, and a product collection and storage tank connected sequentially. A first valve is provided between the precursor solution storage tank and the injection pump. Several one-way valves are provided on the reaction pipeline, which is situated within an ultrasonic bath. The precursor solution storage tank is used to store the prepared precursor solution; The first valve is used to control the opening and closing of the precursor solution storage tank; The injection pump is used to inject the precursor solution from the precursor solution storage tank into the reaction pipeline; The reaction pipeline serves as a container for the synthesis reaction to occur. The one-way valve is used to ensure that the solution is fed from the precursor solution storage tank into the product collection storage tank in a one-way and step-by-step manner, ensuring the gradual progress of the reaction and avoiding backflow. The ultrasonic pool contains water, which is used to generate ultrasonic waves and control the temperature. The product collection and storage tank is used to store the reaction products.

[0008] Furthermore, the preparation device also includes a sampling and detection module, which includes a sampling tank connected to a product collection and storage tank via a second valve, for taking a portion of the sample from the product collection and storage tank for testing during the reaction.

[0009] Furthermore, the preparation apparatus also includes a pressure compensation module, which comprises a gas cylinder, a pressure control and compensation control system, and a pressure gauge. The gas cylinder is connected to the precursor solution storage tank through the pressure control and compensation control system. Under the control of the pressure control and compensation control system, the gas cylinder compensates for the pressure in the precursor solution storage tank, keeping it consistent with the pressure in the reaction pipeline, so that the precursor can be stably input into the reaction pipeline. The pressure gauge is installed on the reaction pipeline to collect the pressure values ​​in the reaction pipeline and feed them back to the pressure control and compensation control system.

[0010] Furthermore, the reaction pipeline is S-shaped and arranged in an ultrasonic pool with heating capability. A one-way valve is arranged at intervals in the reaction pipeline to ensure that the precursor solution flows unidirectionally from the injection end through the passage to the product collection and storage tank, ensuring sufficient reaction time to generate the final one-dimensional high-entropy oxide nanowires.

[0011] A method for preparing high-entropy nano-oxide nanowires based on ultrasonic micro-pressure, the method comprising the following steps: Step S1: Based on the elemental composition and ratio of the high-entropy oxide nanowires to be prepared, inject the precursor solution of the required elements into the precursor solution storage tank and stir evenly to form the required precursor solution. Step S2: Open the first valve and injection pump, and inject the mixed precursor solution into the reaction pipeline with micro-pressure at a certain rate. Deionized water is injected into the ultrasonic pool and heated to the set temperature, so that the S-shaped reaction pipelines densely packed therein can carry out ultrasonic reaction at the set temperature. At the same time, the micro-pressure formed in the closed reaction passage by heating also ensures the formation of one-dimensional oxide nanowires. Step S3: Open the second valve, extract the product from the product collection and storage tank through the sampling tank, and obtain high-entropy oxide nanowire powder through filtration, washing and drying.

[0012] The beneficial effects of this invention are: 1. This invention utilizes a micro-pressure reaction environment and ultrasonic reaction to achieve the controllable preparation of high-entropy oxide nanowires with uniform elemental distribution through the formulation of a simple salt solution.

[0013] 2. By controlling the reaction temperature (the heating temperature of the ultrasonic pool), the pressure in the reaction channel can be controlled, the reaction kinetics can be controlled, and thus the length of the prepared one-dimensional nanowires can be controlled.

[0014] 3. Through a closed micro-pressure reaction system, continuous preparation of high-entropy oxide nanowires can be achieved, making it easy to achieve large-scale preparation of high-entropy oxide nanowires. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the preparation apparatus of the present invention; Figure 2 The La(Fe) prepared at 90℃ in Example 1 of this invention 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 O3 nanowires; Figure 3 The La(Fe) prepared at 99℃ in Comparative Example 1 of this invention 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 O3 nanowires; Figure 4 The La(Fe) aggregate synthesized under no-pressure conditions in Comparative Example 2 of this invention is an example of this invention. 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2O3 nanoparticles.

[0016] The following are the labels in the diagram: 1. Precursor solution storage tank; 2. First valve; 3. Injection pump; 4. Reaction pipeline; 5. Check valve; 6. Ultrasonic pool; 7. Product collection and storage tank; 8. Sampling tank; 9. Second valve; 10. Gas cylinder; 11. Pressure control and compensation control system; 12. Pressure gauge. Detailed Implementation

[0017] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] A device for preparing high-entropy nano-oxide nanowires based on ultrasonic micropressure, the device including a reaction module, such as... Figure 1 As shown, the reaction module includes a precursor solution storage tank 1, an injection pump 3, a reaction pipeline 4, and a product collection and storage tank 7 connected in sequence. A first valve 2 is provided between the precursor solution storage tank 1 and the injection pump 3. Several one-way valves 5 are provided on the reaction pipeline 4, which is located in an ultrasonic bath 6. The precursor solution storage tank 1 is used to store the prepared precursor solution; The first valve 2 is used to control the opening and closing of the precursor solution storage tank 1; The injection pump 3 is used to inject the precursor solution from the precursor solution storage tank 1 into the reaction pipeline 4; The reaction pipeline 4 serves as the container for the synthesis reaction; The one-way valve 5 is used to ensure that the solution is fed from the precursor solution storage tank 1 into the product collection storage tank 7 in a one-way and step-by-step manner, so as to ensure the gradual progress of the reaction and avoid backflow. The ultrasonic pool 6 contains water, which is used to generate ultrasonic waves and control the temperature. The product collection and storage tank 7 is used to store the reaction products.

[0019] The preparation apparatus also includes a sampling and testing module, which includes a sampling tank 8. The sampling tank 8 is connected to a product collection and storage tank 7 via a second valve 9. It is used to take a portion of the sample from the product collection and storage tank 7 for testing during the reaction. The second valve 9 is used to isolate or connect the product collection and storage tank 7 and the sampling tank 8 to ensure the pressure in the former.

[0020] The preparation apparatus also includes a pressure compensation module, which includes a gas cylinder 10, a pressure control and compensation control system 11, and a pressure gauge 12. The gas cylinder 10 is connected to the precursor solution storage tank 1 through the pressure control and compensation control system 11. The pressure control and compensation control system 11 is used to control and adjust the output pressure of the gas cylinder 10. Under the control of the pressure control and compensation control system 11, the gas cylinder 10 compensates for the pressure of the precursor solution storage tank 1, making it consistent with the pressure in the reaction pipeline 4, so that the precursor can be stably input into the reaction pipeline 4. The pressure gauge 12 is installed on the reaction pipeline 4 to collect the pressure value in the reaction pipeline 4 and feed it back to the pressure control and compensation control system 11.

[0021] The reaction channel 4 is S-shaped and arranged in an ultrasonic pool 6 with heating capability. A one-way valve 5 is arranged at intervals in the reaction channel 4 to ensure that the precursor solution flows unidirectionally from the injection end through the passage to the product collection and storage tank 7, ensuring sufficient reaction time to generate the final one-dimensional high-entropy oxide nanowires.

[0022] A method for preparing high-entropy nano-oxide nanowires based on ultrasonic micro-pressure, the method comprising the following steps: Step S1: Based on the elemental composition and ratio of the high-entropy oxide nanowires to be prepared, inject the precursor solution of the required elements into the precursor solution storage tank 1 and stir evenly to form the required precursor solution. Step S2: Open the first valve 2 and the injection pump 3, and inject the mixed precursor solution into the reaction pipe 4 with micro-pressure at a certain rate. Deionized water is injected into the ultrasonic pool 6 and heated to the set temperature, so that the S-shaped reaction pipe 4, which is densely packed with it, can carry out ultrasonic reaction at the set temperature. At the same time, the micro-pressure formed in the closed reaction passage by heating also ensures the formation of one-dimensional oxide nanowires. Step S3: Open the second valve 9, extract the product from the product collection and storage tank 7 through the sampling tank 8, and obtain high-entropy oxide nanowire powder through filtration, washing and drying. Example 1

[0023] (1) The prepared 1 mol / L La(NO3)3, Fe(NO3)3, Co(NO3)2, Ni(NO3)3, Mn(NO3)2, Cu(NO3)2, urea solution and 10% ammonia solution were respectively placed into storage containers; (2) The prepared solution is injected from the storage container into the precursor solution storage tank 1 in a ratio of 5:1:1:1:1:1:0.5:0.5 using a transfer pump. The mixture is stirred and mixed evenly to form a precursor solution. (3) Turn on the ultrasonic pool 6, set the ultrasonic power to 600W, and set the heating temperature to 90°C. o C, maintain a constant temperature and keep the pressure in the reaction pathway at 1.5 atmospheres; (4) The mixed precursor solution is continuously injected into the ultrasonic reaction pipeline 4 with micro-pressure by the injection pump 3. Multiple one-way valves 5 are installed in the reaction pipeline 4 to ensure that the solution gradually passes through different areas of the reaction pipeline 4, increasing its residence time in the reaction pipeline 4, and controlling the flow time of the solution in the ultrasonic pool 6 to 1 hour, that is, controlling the reaction time to 1 hour. (5) After the reaction solution flows through the entire reaction pipeline 4, it is injected into the product collection and storage tank 7. The amount of solution in the product collection and storage tank 7 is monitored by the detection device. When it reaches 2 / 3, 1 / 3 is extracted by the extraction device and 1 / 3 of the solution is retained in the product collection and storage tank 7 to ensure the sealing. (6) The extracted solution is filtered, washed and dried to obtain La(Fe) 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 O3 nanowires, which are like Figure 2 As shown.

[0024] Comparative Example 1: La(Fe) 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 Preparation of O3 nanowires (prepared at 99℃) (1) Other reaction parameters and procedures are the same as in the example, except that the reaction temperature is increased to 99°C; (2) The prepared product is still La(Fe) 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 O3 nanowires, but with a significantly increased length, such as Figure 3 As shown.

[0025] Comparative Example 2: La(Fe) under no pressure 0.2 Co 0.2 Ni 0.2 Mn 0.2 Cu 0.2 Synthesis of O3 nanoparticles (1) The prepared 1 mol / L La(NO3)3, Fe(NO3)3, Co(NO3)2, Ni(NO3)3, Mn(NO3)2, Cu(NO3)2, urea solution and 10% ammonia solution were respectively placed into storage containers; (2) The prepared solution is injected from the storage container into the precursor solution storage tank 1 in a ratio of 5:1:1:1:1:1:0.5:0.5 using a transfer pump. The mixture is stirred and mixed evenly to form a precursor solution. (3) Turn on the ultrasonic pool 6, set the ultrasonic power to 600W, and set the heating temperature to 90°C. o C, maintain a constant temperature; (4) Use an injection pump to continuously inject the mixed precursor solution into an open reaction vessel, with the gas pressure equal to atmospheric pressure, and react for 1 hour; (5) The reaction solution was filtered, clarified, and dried. The product was collected and determined by electron microscopy to be nanoparticles under pressureless reaction conditions. Figure 4 As shown.

[0026] Furthermore, it should be noted that, unless otherwise specified or indicated, the terms "first," "second," etc., in the specification are used only to distinguish the various components, elements, steps, etc. in the specification, and are not used to indicate the logical or sequential relationships between the various components, elements, steps, etc.

[0027] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-entropy nanooxide nanowire preparation device based on ultrasonic micro-pressure, characterized in that, The preparation apparatus includes a reaction module, which comprises a precursor solution storage tank (1), an injection pump (3), a reaction pipeline (4), and a product collection and storage tank (7) connected in sequence. A first valve (2) is provided between the precursor solution storage tank (1) and the injection pump (3). Several one-way valves (5) are provided on the reaction pipeline (4), which is located in an ultrasonic bath (6). The precursor solution storage tank (1) is used to store the prepared precursor solution; The first valve (2) is used to control the opening and closing of the precursor solution storage tank (1); The injection pump (3) is used to inject the precursor solution from the precursor solution storage tank (1) into the reaction pipeline (4); The reaction pipe (4) serves as the container for the synthesis reaction; The one-way valve (5) is used to ensure that the solution is fed from the precursor solution storage tank (1) into the product collection storage tank (7) in a one-way and step-by-step manner, so as to ensure the gradual progress of the reaction and avoid backflow. The ultrasonic pool (6) contains water, which is used to generate ultrasonic waves and control the temperature. The product collection and storage tank (7) is used to store the reaction products. 2.The high-entropy nano-oxide nanowire preparation device based on ultrasonic micro-pressure according to claim 1, wherein, The preparation device also includes a sampling and detection module, which includes a sampling tank (8) connected to a product collection and storage tank (7) via a second valve (9) for taking out a portion of the sample from the product collection and storage tank (7) during the reaction for testing. 3.The high-entropy nano-oxide nanowire preparation device based on ultrasonic micro-pressure according to claim 1, wherein, The preparation device also includes a pressure compensation module, which includes a gas cylinder (10), a pressure control and compensation control system (11), and a pressure gauge (12). The gas cylinder (10) is connected to the precursor solution storage tank (1) through the pressure control and compensation control system (11). Under the control of the pressure control and compensation control system (11), the gas cylinder (10) compensates the pressure of the precursor solution storage tank (1) to keep it consistent with the pressure in the reaction pipeline (4), so that the precursor can be stably input into the reaction pipeline (4). The pressure gauge (12) is set on the reaction pipeline (4) to collect the pressure value in the reaction pipeline (4) and feed it back to the pressure control and compensation control system (11). 4.The high-entropy nanooxide nanowire preparation device based on ultrasonic micro-pressure according to claim 1, wherein, The reaction pipeline (4) is S-shaped and arranged in an ultrasonic pool (6) with heating capability. A one-way valve (5) is arranged at intervals in the reaction pipeline (4) to ensure that the precursor solution flows unidirectionally from the injection end through the passage to the product collection and storage tank (7), ensuring sufficient reaction time to generate the final one-dimensional high-entropy oxide nanowires.

5. A method of preparing high-entropy nanooxide nanowires from the apparatus of any one of claims 1-4, comprising: The method includes the following steps: Step S1: Based on the elemental composition and ratio of the high-entropy oxide nanowires to be prepared, inject the precursor solution of the required elements into the precursor solution storage tank (1) and stir evenly to form the required precursor solution; Step S2: Open the first valve (2) and the injection pump (3) to inject the mixed precursor solution into the reaction pipe (4) with micro-pressure at a certain rate. Deionized water is injected into the ultrasonic pool (6) and heated to the set temperature so that the S-shaped reaction pipe (4) densely packed in it can carry out ultrasonic reaction at the set temperature. At the same time, the micro-pressure formed in the closed reaction passage also ensures the formation of one-dimensional oxide nanowires. Step S3: Open the second valve (9), extract the product from the product collection and storage tank (7) through the sampling tank (8), and obtain high-entropy oxide nanowire powder by filtration, washing and drying.

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