Modified vanadium dioxide powder and preparation method thereof

Abstract

The application discloses modified vanadium dioxide powder and a preparation method thereof, and belongs to the field of vanadium dioxide powder. The method for preparing the modified vanadium dioxide powder comprises the following steps: firstly, preparing VO2 with good crystallinity through a two-step method; then, improving the stability of the VO2 and increasing the number of hydroxyl groups on the surface of the VO2 through water bath modification; and finally, grafting or adsorbing a surface modifier on the VO2 under the mechanical chemical action of ball milling, so as to improve the dispersibility and stability. The VO2 nano-powder prepared by the method has good crystallinity, can isolate external air and moisture, and can enhance the acid resistance, oxidation resistance and environmental durability of the VO2 nano-powder.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of vanadium dioxide powder, in particular to a modified vanadium dioxide powder and a preparation method thereof. BACKGROUND

[0002] Vanadium dioxide (VO2) is a metal oxide with thermochromic properties, which can exhibit a first-order reversible phase transition when the ambient temperature is higher than its phase transition temperature (68℃). It can transform from a low-temperature semiconductor phase to a high-temperature metal phase, resulting in changes in electrical and optical properties. It can change from high transmission to high reflection of near-infrared light, so it can be applied to smart windows to regulate near-infrared light.

[0003] Currently, there are still some limitations in the application of VO2 on smart windows: high phase transition temperature, poor infrared shielding performance, unattractive color, and poor environmental durability, etc. Researchers have improved the optical properties and phase transition characteristics of VO2 to some extent by doping elements (W, Nb, etc.), coating, and compounding with other organic / inorganic materials. Chinese patent CN109294277A discloses a surface modified vanadium dioxide and a preparation method thereof. The patent disperses vanadium dioxide in ethanol, adds a silicon source dropwise, and obtains a silica-coated vanadium dioxide powder after reaction in a water bath. Then the coated powder is dispersed in a solvent, and a silane coupling agent is added. Finally, the surface modified vanadium dioxide is obtained. This method improves the oxidation resistance of VO2, enhances the affinity of VO2 with organic materials, and makes it easy to be compounded with polymers, laying a foundation for the compounding of organic and inorganic materials. Although the stability is improved by coating, it is difficult to achieve uniform coating, and the process is complicated and time-consuming. Therefore, it is necessary to explore new methods to improve the dispersibility and stability of VO2. SUMMARY

[0004] In view of the defects or improvement needs of the prior art, the purpose of the present application is to provide a preparation method of modified vanadium dioxide powder, which overcomes the defects of complicated preparation process, long reaction time, low efficiency, and poor dispersibility in the prior art.

[0005] In order to achieve the above-mentioned purpose or other purposes, the present application provides a preparation method of modified vanadium dioxide powder, which mainly realizes the following technical scheme.

[0006] A preparation method of modified vanadium dioxide powder, comprising the following steps:

[0007] (1) uniformly mixing a vanadium source and a reducing agent to obtain a mixed ingredient; adding the mixed ingredient into a ball milling device and adding grinding balls for ball milling treatment to obtain a precursor;

[0008] (2) calcining the precursor obtained in step (1) under vacuum environment to obtain VO2 powder;

[0009] (3) dispersing the VO2 powder obtained in step (2) in a solvent, uniformly dispersing the same by ultrasonic, adding surface modifier I, and carrying out reaction in a water bath, and then obtaining modified nano powder after centrifugation and vacuum drying;

[0010] (4) uniformly mixing the modified nano powder obtained in step (3) with grinding aids, adding to a ball milling device, adding surface modifier II, and carrying out grinding treatment, and then obtaining modified vanadium dioxide powder after centrifugation and drying.

[0011] Further, the vanadium source is selected from one or more of V2O3, V2O5, VOSO4 and NH4VO3.

[0012] Further, the reducing agent is selected from one or more of glucose, fructose, sucrose, maltose, starch and cellulose.

[0013] Further, the mass ratio of the vanadium source to the reducing agent is (3-60):1. The ball milling device used in the present application can be a conventional ball milling device in the art. Further, the grinding ball is a zirconium oxide grinding ball.

[0014] The particle size of the grinding ball used in the present application is 0.2mm-5mm.

[0015] Further, the ball-to-material ratio in step (1) is (10-20):1.

[0016] Further, the rotation speed during the ball milling treatment in step (1) is 200-400r / min, and the ball milling time is 1h-5h.

[0017] Further, the calcination temperature in step (2) is 300℃-700℃, the temperature rising speed during the calcination is 5-10℃ / min, and the holding time is 60min-360min.

[0018] 10℃ / min, and the holding time is 60min-360min.

[0019] Further, in step (3), the solvent is deionized water.

[0020] Further, in step (3), the mass ratio of the solvent to the VO2 powder is (30-100):1.

[0021] Further, in step (3), the surface modifier I is selected from one or more of ascorbic acid, dodecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium bromide, sodium dodecyl sulfonate, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate and polyvinyl pyrrolidone.

[0022] Further, the mass ratio of the surface modifier I to the VO2 powder in step (3) is (0.1-1) : 1.

[0023] Further, the ultrasonic time in step (3) is 0.5h-2h. Preferably, the water bath reaction temperature is 40℃-90℃, and the reaction time is 0.5h-4h. Preferably, centrifugal treatment is performed after the water bath reaction in step (3). More preferably, the centrifugal rate is 2000-12000r / min, and the time is 2min-15min. Further, the vacuum drying temperature in step (3) is 40℃-80℃, and the drying time is 1h-10h.

[0024] Further, the surface modifier II is selected from one or more of 3-aminopropyl triethoxysilane, γ-aminopropyl trimethoxysilane, γ-aminopropyl methyl diethoxysilane, 3-mercaptopropyl triethoxysilane, dodecyl trimethyl ammonium bromide, hexadecyl trimethyl ammonium bromide, sodium dodecyl sulfonate, sodium dodecyl sulfate, sodium dodecyl benzene sulfonate, and polyvinyl pyrrolidone. Preferably, the surface modifier II is 3-aminopropyl triethoxysilane.

[0025] Further, the mass ratio of the surface modifier II to the modified nano-powder in step (4) is (0.1-1) : 1.

[0026] Preferably, the grinding aid in step (4) is selected from one or more of deionized water, methanol, ethanol, and isoamyl alcohol.

[0027] Further, the mass ratio of the grinding aid to the modified nano-powder in step (4) is (10-20) : 1.

[0028] Further, the ball-to-material ratio in the ball milling treatment in step (4) is (30-80) : 1, the grinding ball particle size is 0.2mm-5mm, the rotation speed during the ball milling treatment is 100-500r / min, and the ball milling time is 0.5h-12h.

[0029] Preferably, centrifugal treatment is performed after the reaction in step (4). More preferably, the centrifugal rate is 2000-12000r / min, and the centrifugal time is 2min-15min. Drying is performed after the centrifugation.

[0030] Further, the drying temperature in step (4) is 40-70℃, and the time is 1h-12h.

[0031] Another aspect of the present application also protects a modified vanadium dioxide powder prepared by the above method. The modified vanadium dioxide powder of the present application has a particle size of 30nm-60nm.

[0032] The method for preparing modified vanadium dioxide powder provided by the application first prepares VO2 powder with good crystallinity through a two-step method, then improves the stability and increases the number of hydroxyl groups on the surface through water bath modification, and finally uses ball milling to graft or adsorb surface modifiers on the VO2 under the action of mechanochemistry, thereby improving the dispersibility and stability through secondary modification. The VO2 nanopowder prepared by the method of the application has good crystallinity, can isolate external air and moisture, and enhances its acid resistance, oxidation resistance and environmental durability. Moreover, the phase transition temperature of the VO2 is reduced without doping elements, and the powder surface is positively charged after modification by the surface modifier II, which is conducive to the later compounding with other materials, expands the research field of VO2, and improves the performance. In addition, the dispersibility of the VO2 in water and ethanol is enhanced through modification, and the optical performance of the thin film prepared therefrom is excellent. The preparation process of the application is simple, low in cost, safe and pollution-free, and is conducive to large-scale production and application. BRIEF DESCRIPTION OF DRAWINGS

[0033] Figure 1 The powder X-ray diffraction (XRD) pattern of the modified vanadium dioxide powder prepared for Examples 1-4 of the application.

[0034] Figure 2 The powder X-ray diffraction (XRD) pattern of the nanopowder prepared for Example 1 and Comparative Example 2 of the application.

[0035] Figure 3 The powder differential scanning calorimetry (DSC) pattern of the modified nanopowder prepared for Examples 1-4 and Comparative Example 1 of the application.

[0036] Figure 4 The ultraviolet-visible-near infrared transmittance graph of the vanadium dioxide nanopowder prepared for Examples 1-4 and Comparative Example 2 of the application coated on a glass sheet.

[0037] Figure 5 The transmission electron microscope (TEM) graph of the vanadium dioxide nanopowder prepared for Example 1 and Comparative Example 2 of the application. DETAILED DESCRIPTION

[0038] The embodiments of the application are described below by specific specific embodiments, and those skilled in the art can easily understand other advantages and effects of the application from the disclosure of the specification. The application can also be implemented or applied by different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the application.

[0039] It should be noted that the following embodiments and features in the embodiments can be combined with each other in the case of no conflict. It should also be understood that the terms used in the embodiments of the present application are for the purpose of describing specific embodiments, and are not intended to limit the protection scope of the present application. The test methods in the following embodiments not noted with specific conditions are generally according to the conventional conditions, or according to the conditions suggested by the manufacturers.

[0040] When the embodiments give numerical ranges, it should be understood that, unless otherwise stated by the present application, both ends of each numerical range and any numerical value between the two ends can be selected. Unless otherwise defined, all technical and scientific terms used in the present application are consistent with the mastery of the prior art by those skilled in the art and the description of the present application, and any method, equipment and material of the prior art similar or equivalent to the method, equipment and material described in the embodiments of the present application can be used to realize the present application.

[0041] Embodiment 1

[0042] A preparation method of ball-milling modified VO2 to enhance dispersion stability, comprising the following steps:

[0043] (1) mixing vanadium pentoxide 2.89 g and glucose 0.29 g uniformly to obtain a mixed ingredient; adding the mixed ingredient into a ball milling device, adding zirconium oxide grinding balls 63.6 g, rotating at 400 r / min, and obtaining a precursor after ball milling for 5 h;

[0044] (2) scraping the precursor in the tank with a medicine spoon, and then placing it in an annealing furnace, calcining in a vacuum environment at 500℃ for 2 h, and obtaining a well-crystallized VO2 nano-powder with a heating rate of 8℃ / min;

[0045] (3) taking 1.0 g of the above nano-powder into a beaker, adding 80 mL of deionized water, and ultrasonicating for 1 h; then adding 0.3 g of ascorbic acid into the above solution, transferring the beaker into a water bath kettle at 85℃, and reacting for 1 h; taking out the beaker and standing, and after cooling, placing the solution in a centrifuge at a rotating speed of 10000 r / min, and centrifuging for 10 min; finally, transferring the bottom precipitate into a vacuum drying oven at 40℃, and drying for 8 h; and grinding with a mortar to obtain ascorbic acid modified VO2 nano-powder.

[0046] (4) Take the above-mentioned 0.5 g of nano-powder and place it in a ball mill tank, add 8 mL of ethanol, 2 mL of deionized water, 33 g of grinding balls, introduce 0.1 g of 3-aminopropyl triethoxysilane, rotate at a speed of 450 r / min, and mill for 4 h; secondly, transfer the solution in the tank to a centrifuge, rotate at a speed of 8000 r / min, centrifuge for 5 min, and add a mixed solution of ethanol and water to repeatedly clean twice, after the cleaning is completed, place the obtained solid in a vacuum drying oven at 40°C, dry for 10 h, and remove the residual ethanol. Finally, obtain the twice-modified nano-powder by means of a mortar.

[0047] The prepared powder is subjected to X-ray diffraction (XRD) test (instrument model: Smart-Lab SE), and the result is shown in FIG. 1. As shown in FIG. 1, the X-ray diffraction pattern is completely matched with the standard card pattern of vanadium dioxide (VO2), which indicates that the modified powder is still M-phase vanadium dioxide, and there is no other impurity phase. Figure 1

[0048] Example 2

[0049] A preparation method for improving the dispersion stability of VO2 by ball milling modification, comprising the following steps:

[0050] (1) Mix vanadium pentoxide 2.89 g and glucose 0.29 g uniformly to obtain a mixed ingredient; add it into a ball milling device, add zirconium oxide grinding balls 63.6 g, rotate at a speed of 400 r / min, and mill for 5 h to obtain a precursor;

[0051] (2) Use a medicine spoon to scrape the precursor in the tank, and then place it in an annealing furnace, anneal and calcine at 500°C in a vacuum environment for 2 h, and the temperature rising rate is 8°C / min, to obtain VO2 nano-powder with good crystallinity;

[0052] (3) Take the above-mentioned 1.0 g of nano-powder and place it in a beaker, add 80 mL of deionized water, and ultrasonic for 1 h, then add 0.3 g of ascorbic acid to the above-mentioned solution, transfer the beaker to a water bath kettle at 85°C, react for 1 h, take out the beaker and stand, after cooling, place the solution in a centrifuge, rotate at a speed of 10000 r / min, centrifuge for 10 min, finally transfer the bottom precipitate to a vacuum drying oven at 40°C, dry for 8 h, and obtain the ascorbic acid-modified VO2 nano-powder by means of a mortar.

[0053] ​(4) Take the above 0.5g nanometer powder in the ball mill tank, add 8mL ethanol, 2mL deionized water, 33g grinding ball, introduce polyvinylpyrrolidone 0.19g, rotate speed 450r / min, ball mill 4h; secondly, transfer the solution in the tank to the centrifuge, rotate speed 8000r / min, centrifuge 5min, and add the mixed solution of ethanol and water repeatedly wash twice, after the end of cleaning, the obtained solid is placed in 40℃ vacuum drying oven, dry 10h, remove residual ethanol. Finally, with the help of mortar grinding, get the secondary modified nanometer powder.

[0054] X-ray diffraction (XRD) test results show that the vanadium dioxide powder is M phase.

[0055] Example 3

[0056] A ball milling modified VO2 enhances the dispersion stability of the preparation method, comprising the following steps:

[0057] (1) mix vanadium pentoxide 2.89g, glucose 0.29g uniformly, get mixed ingredients; add it to the ball milling device, add zirconium oxide grinding ball 63.6g, rotate speed 400r / min, ball mill 5h to get the precursor;

[0058] (2) scrape the precursor in the tank with a medicine spoon, then put it in the annealing furnace, calcine 2h in the vacuum environment of 500℃, the heating rate is 8℃ / min, get the well crystallized VO2 nanometer powder;

[0059] (3) take the above 1.0g nanometer powder in the beaker, add 80mL deionized water, ultrasonic 1h, then add 0.3g cetyltrimethylammonium bromide to the above solution, transfer the beaker to the water bath pot of 85℃, react 1h, take out the beaker and stand, after cooling, put the solution in the centrifuge, rotate speed 10000r / min, centrifuge 10min, finally transfer the bottom precipitate to 40℃ vacuum drying oven, dry 8h, get the cetyltrimethylammonium bromide modified VO2 nanometer powder after using mortar grinding.

[0060] (4) take the above 0.5g nanometer powder in the ball mill tank, add 8mL ethanol, 2mL deionized water, 33g grinding ball, introduce sodium dodecyl sulfate 0.19g, rotate speed 450r / min, ball mill 4h; secondly, transfer the solution in the tank to the centrifuge, rotate speed 8000r / min, centrifuge 5min, and add the mixed solution of ethanol and water repeatedly wash twice, after the end of cleaning, the obtained solid is placed in 40℃ vacuum drying oven, dry 10h, remove residual ethanol. Finally, with the help of mortar grinding, get the secondary modified nanometer powder.

[0061] X-ray diffraction (XRD) test results show that the vanadium dioxide powder is M phase.

[0062] Example 4

[0063] A preparation method of a ball-milling modified VO2 enhanced dispersion stability, comprising the following steps:

[0064] (1) mixing vanadium pentoxide 2.89 g and glucose 0.29 g uniformly to obtain a mixed ingredient; adding the mixed ingredient into a ball-milling device, adding zirconium oxide grinding balls 63.6 g, rotating at a speed of 400 r / min, and obtaining a precursor after ball-milling for 5 h;

[0065] (2) scraping the precursor in the tank with a medicine spoon, and then placing the precursor in an annealing furnace to calcine under a vacuum environment at 500℃ for 2 h at a temperature rising rate of 8℃ / min, to obtain a VO2 nano powder with good crystallinity;

[0066] (3) taking 1.0 g of the nano powder above into a beaker, adding 80 mL of deionized water, and ultrasonicating for 1 h, then adding 0.3 g of polyvinylpyrrolidone into the solution above, transferring the beaker into a water bath kettle at 85℃, and reacting for 1 h; taking out the beaker and standing, and then placing the solution into a centrifuge at a rotating speed of 10,000 r / min and centrifuging for 10 min; finally, transferring the bottom precipitate into a vacuum drying oven at 40℃, and drying for 8 h, and then grinding with a mortar to obtain a polyvinylpyrrolidone modified VO2 nano powder.

[0067] (4) taking 0.5 g of the nano powder above into a ball-milling tank, adding 8 mL of ethanol, 2 mL of deionized water, and 33 g of grinding balls, introducing 0.19 g of cetyltrimethylammonium bromide, rotating at a speed of 450 r / min, and ball-milling for 4 h; then transferring the solution in the tank into a centrifuge at a rotating speed of 8,000 r / min and centrifuging for 5 min, and repeatedly washing twice with a mixed solution of ethanol and water; after the washing is completed, placing the obtained solid into a vacuum drying oven at 40℃, and drying for 10 h to remove residual ethanol; finally, grinding with a mortar to obtain a twice modified nano powder.

[0068] The X-ray diffraction (XRD) test result shows that the vanadium dioxide powder is in M phase.

[0069] Comparative Example 1

[0070] (1) mixing vanadium pentoxide 2.89 g and glucose 0.29 g uniformly to obtain a mixed ingredient; adding the mixed ingredient into a ball-milling device, adding zirconium oxide grinding balls 63.6 g, rotating at a speed of 400 r / min, and obtaining a precursor after ball-milling for 5 h;

[0071] (2) scraping the precursor in the tank with a medicine spoon, and then placing the precursor in an annealing furnace to calcine under a vacuum environment at 500℃ for 2 h at a temperature rising rate of 8℃ / min, to obtain a VO2 nano powder with good crystallinity;

[0072] (3) Take 1.0 g of the above-mentioned nano-powder and place it in a beaker, add 80 mL of deionized water, and ultrasonic for 1 h. Then add 0.3 g of ascorbic acid to the above-mentioned solution, and transfer the beaker to a water bath at 85°C, and react for 1 h. Take out the beaker and let it stand, and after cooling, place the solution in a centrifuge at a speed of 10,000 r / min, and centrifuge for 10 min. Finally, transfer the bottom precipitate to a vacuum drying oven at 40°C, and dry for 8 h. After grinding with a mortar, the ascorbic acid-modified VO2 nano-powder is obtained.

[0073] (4) Take 0.5 g of the above-mentioned nano-powder and place it in a ball mill tank, add 8 mL of ethanol and 2 mL of deionized water, and 33 g of grinding balls. Do not add any surface modifier, and mill at a speed of 450 r / min for 4 h. Then transfer the solution in the tank to a centrifuge at a speed of 8,000 r / min, and centrifuge for 5 min. Add a mixed solution of ethanol and water repeatedly for two times for cleaning. After cleaning, place the obtained solid in a vacuum drying oven at 40°C, and dry for 10 h to remove residual ethanol. Finally, grind with a mortar to obtain the nano-powder.

[0074] The X-ray diffraction (XRD) test results show that the vanadium dioxide powder is in the M phase.

[0075] Comparative Example 2

[0076] Steps (1) and (2) in the present comparative example are the same as steps (1) and (2) in Example 1, except that no surface modifier is added in steps (3) and (4), and finally the VO2 nano-powder without modification is obtained.

[0077] Performance characterization

[0078] 1. The powders obtained in Examples 1-4 and Comparative Example 2 are characterized by X-ray diffraction (XRD) instrument (instrument model: Smart-Lab SE), and the results are shown in Figure 1 and Figure 2 It can be seen from the figures that the characteristic peaks of Examples 1-4 are well matched with the VO2 standard card (JCPDS NO: 43-1051), and no impurity peak appears, indicating that the modified powder is still M-phase vanadium dioxide, and there is no other impurity phase. The XRD diffraction peak of the powder prepared in Comparative Example 2 appears V6O 13 impurity peak, indicating that it has been oxidized.

[0079] 2. The powders prepared in Examples 1-4 and Comparative Example 1 are respectively measured for phase transition temperature and enthalpy by differential scanning calorimeter (DSC 25, TA, USA) at a heating / cooling rate of 10°C / min and a temperature range of -10-110°C, and the results are shown in Figure 3As shown, the powder prepared by the present application has good crystallinity, and the phase transition temperature of the powder of Example 1 is about 66℃.

[0080] 3, the powders obtained from Examples 1-4 and Comparative Example 2 were coated on glass sheets, and the transmittance was tested by using a UV-visible-near infrared spectrophotometer (instrument model: UV-3600Plus), and the test results are shown in Table 1. Figure 4 As shown in the figure, it can be seen from the figure that the solar light modulation ability of the powders prepared in Examples 1-4 is obviously better than that of the powder of Comparative Example 2 (Table 1), which indicates that the presence of the surface modifier reduces the oxidation of vanadium dioxide, and reduces the contact between vanadium dioxide particles due to their long chains and steric hindrance effect. It can be seen that the vanadium dioxide nanopowder obtained by the method of the present application has better dispersibility and stability, thereby having excellent optical performance.

[0081] Table 1 Solar light modulation ability of different thin films

[0082]

[0083] Table 2 Zeta potential values of different powders

[0084]

[0085] 4, Table 2 lists the Zeta potential values of different powders, and it is found that the surface of the powder of Example 1 has positive electric property, because the amino group in the silane coupling agent shows positive electric property, thereby causing the surface of vanadium dioxide to have positive charge; while the surfaces of vanadium dioxide modified by other several surface active agents have negative electric property, which indicates that they do not have the function of changing the electric property of VO2.

[0086] 5, the powders obtained from Examples 1 and Comparative Example 2 were characterized by using a transmission electron microscope (instrument model: JEM-2100F), and the results are shown in Table 3. Figure 5 As shown in the figure, it can be seen from the figure that the solar light modulation ability of the powders prepared in Examples 1-4 is obviously better than that of the powder of Comparative Example 2 (Table 1), which indicates that the presence of the surface modifier reduces the oxidation of vanadium dioxide, and reduces the contact between vanadium dioxide particles due to their long chains and steric hindrance effect. It can be seen that the vanadium dioxide nanopowder obtained by the method of the present application has better dispersibility and stability, thereby having excellent optical performance.

[0087] In summary, the VO2 nanopowder prepared by the application has good crystallinity, can isolate external air and moisture, and enhances its acid resistance, oxidation resistance and environmental durability. Moreover, the phase transition temperature of VO2 is reduced without doping elements; after modification by the surface modifier II, especially after modification by 3-aminopropyl triethoxysilane, the powder surface has positive charges, which is conducive to the later compounding with other materials, expands the research field of VO2, and improves the performance. The preparation process of the application is simple, low in cost, safe and pollution-free, and is conducive to large-scale production and application.

[0088] The above examples only illustrate the principles and effects of the application, and are not intended to limit the application. Any person skilled in the art can modify or change the above examples without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical idea disclosed by the application should be covered by the claims of the application.

Claims

1. A method for producing a modified vanadium dioxide powder, characterized by comprising the steps of: The method comprises the following steps: ​ (1) uniformly mixing a vanadium source and a reducing agent to obtain a mixed ingredient; adding the mixed ingredient into a ball milling device, adding grinding balls to perform ball milling treatment, and obtaining a precursor; (2) performing calcination treatment on the precursor obtained in step (1) under a vacuum environment to obtain a VO2 powder; (3) dispersing the VO2 powder obtained in step (2) in a solvent, uniformly dispersing the VO2 powder through ultrasonic treatment, adding a surface modifier I, performing reaction in a water bath, and obtaining a modified nano powder through centrifugation and vacuum drying after the reaction is completed; (4) uniformly mixing the modified nano powder obtained in step (3) with a grinding aid, adding the surface modifier II into the ball milling device, adding grinding balls to perform grinding treatment, and obtaining a modified vanadium dioxide powder through centrifugation and drying after the reaction is completed; The surface modifier I in step (3) is selected from one or more of ascorbic acid, cetyltrimethylammonium bromide and polyvinylpyrrolidone; The mass ratio of the surface modifier I to the VO2 powder in step (3) is (0.1-1):1; The surface modifier II is selected from one or more of 3-aminopropyltriethoxysilane, cetyltrimethylammonium bromide, sodium dodecyl sulfate and polyvinylpyrrolidone; The mass ratio of the surface modifier II to the modified nano powder in step (4) is (0.1-1):

1.

2. The production method according to claim 1, wherein The mass ratio of the vanadium source to the reducing agent is (3-60):

1.

3. The production method according to claim 1, wherein The ball-to-material ratio in step (1) is (10-20):

1.

4. The production method according to claim 1, wherein One or more of the following technical features is / are included: The rotating speed during the ball milling treatment in step (1) is 200-400 r / min, and the ball milling time is 1 h-5 h; The calcination treatment temperature in step (2) is 300-700 ℃, the heating speed during the calcination treatment is 5-10 ℃ / min, and the holding time is 60 min-360 min.

5. The production method according to claim 1, wherein The mass ratio of the grinding aid to the modified nano powder in step (4) is (10-20):

1.

6. The modified vanadium dioxide powder prepared by the production method according to any one of claims 1 to 5, wherein the modified vanadium dioxide powder has a particle size of 0.1 to 10 μm. The particle size of the modified vanadium dioxide powder is 30-60 nm.

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