A magnesium fluoride nanomaterial and a preparation method thereof
By controlling the reaction conditions between hydrofluoric acid and magnesium salt, magnesium fluoride nanomaterials with excellent sphericity and good dispersibility were prepared, solving the problems of uneven morphology and complex preparation of magnesium fluoride in the existing technology, and realizing low-cost industrial production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QINGHAI INST OF SALT LAKES OF CHINESE ACAD OF SCI
- Filing Date
- 2026-05-11
- Publication Date
- 2026-06-19
AI Technical Summary
Existing methods for preparing magnesium fluoride result in products with poor sphericity and uneven morphology, and the preparation process is complex, increasing costs and making industrial production more difficult.
Using hydrofluoric acid as the fluorine source, the hydrofluoric acid solution was added to the magnesium salt solution in batches under mild conditions of 10~70℃. By controlling the reaction temperature, time, concentration and dropping rate, magnesium fluoride nanomaterials with excellent sphericity and good dispersibility were prepared.
The sphericity and dispersibility of magnesium fluoride nanomaterials were significantly improved, reducing preparation costs and operational complexity, making them suitable for industrial production.
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Figure CN122233406A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of magnesium fluoride preparation technology, specifically relating to a magnesium fluoride nanomaterial and its preparation method. Background Technology
[0002] Magnesium fluoride glass exhibits excellent transmittance in the visible and infrared regions and has a low refractive index. Furthermore, due to the higher strength and denser packing of fluorine ions compared to other metals, magnesium fluoride possesses high mechanical strength and relatively stable chemical properties. Based on its superior optical properties, chemical stability, and low refractive index, magnesium fluoride is widely used in optical coatings, catalyst supports, and laser materials, making it a high-performance optical material. It also has extensive applications in catalysis, metallurgy, and semiconductors.
[0003] Spherical magnesium fluoride can better fill molds, reduce forming defects, and achieve a denser packing during the stacking process, thereby increasing the filling density. This further enhances the material's strength, hardness, and heat resistance. Simultaneously, spherical fluoride powder exhibits less friction during transportation and processing, allowing for smoother flow. However, existing methods produce magnesium fluoride products with poor sphericity and uneven morphology, typically appearing as large granules, which affects its optical and mechanical properties. Furthermore, current preparation methods often require special additives, pH adjustments, and external field control to regulate morphology, making the process complex. This not only increases preparation costs and time but also complicates industrial production. Summary of the Invention
[0004] To solve all or some of the above problems, the present invention provides the following technical solutions:
[0005] The first aspect of the present invention provides a method for preparing magnesium fluoride nanomaterials, comprising: adding hydrofluoric acid solution in batches to a magnesium salt solution, and reacting at a temperature of 10~70°C to obtain magnesium fluoride nanomaterials.
[0006] Using hydrofluoric acid as a fluorine source, magnesium fluoride nanomaterials with excellent sphericity and good dispersibility can be prepared. Moreover, the preparation method has mild reaction conditions (10~70℃) and simple operation (no special means such as pH adjustment or external field control are required), making it suitable for industrial production.
[0007] If the reaction temperature is less than 10℃, it is easy to cause incomplete reaction, poor sphericity, and low reaction efficiency; if the reaction temperature is higher, it is easy to cause explosive nucleation and aggregation, while consuming a lot of energy and costing a lot.
[0008] In some embodiments, the concentration of hydrofluoric acid in the hydrofluoric acid solution is 0.2 mol / L to 4.8 mol / L.
[0009] In some embodiments, the concentration of magnesium salt in the magnesium salt solution is 0.04 mol / L to 0.4 mol / L.
[0010] If the reactant concentration is too high or too low, the growth driving force of the prepared product will be insufficient or too strong, resulting in the inability to complete isotropic assembly in all directions, thus leading to poor sphericity. This invention controls the concentrations of hydrofluoric acid and magnesium salt within the aforementioned range, which can further improve the sphericity of the prepared magnesium fluoride nanomaterials.
[0011] In some embodiments, the amount of hydrofluoric acid solution added satisfies the following condition: the molar ratio of hydrogen fluoride to magnesium salt is 1.8:1 to 2.2:1.
[0012] In some embodiments, the magnesium salt contained in the magnesium salt solution is magnesium chloride. When magnesium chloride is used as the magnesium source, the reaction product is hydrogen chloride, which is less likely to introduce other impurity ions, further ensuring the purity of the product.
[0013] In some embodiments, the reaction time is 0.5 h to 8 h. If the reaction time is too short, the nucleation stage will not be completed, the growth will be incomplete, and the sphericity of the product will be poor; if the reaction time is too long, the Oswal ripening process will easily lead to uneven particle size of magnesium fluoride particles.
[0014] The reaction temperature of the preparation method of the present invention can be any value or a range between 10℃, 20℃, 30℃, 40℃, 50℃, 60℃, and 70℃; the reaction time of the present invention can be any value or a range between 0.5h, 1h, 2h, 3h, 4h, 5h, 6h, 7h, and 8h. Preferably, the reaction temperature of the preparation method is 20~40℃, and the reaction time is 1.5h~3h. Within this preferred reaction temperature and reaction time range, the sphericity and dispersibility of the obtained magnesium chloride are further improved.
[0015] In some embodiments, the hydrofluoric acid solution is added to the magnesium salt solution at a dropping rate of 2-15 ml / min. Adding the hydrofluoric acid solution in batches allows for orderly nucleation and growth of the crystals, resulting in good microscopic dispersion, larger particle size, and good sphericity. If the solution is added all at once, it leads to explosive nucleation, resulting in small particles and severe agglomeration.
[0016] In some embodiments, the preparation method further includes: performing solid-liquid separation on the magnesium fluoride suspension obtained from the reaction, and washing and drying the separated magnesium fluoride nanomaterials. The preparation method provided by this invention allows for direct centrifugation and drying after the reaction, eliminating the need for steps such as settling and ultrasonic dispersion.
[0017] Uniform and well-dispersed fluorides exhibit significant advantages in optical and mechanical properties compared to non-uniform and agglomerated products. Furthermore, larger-diameter magnesium fluoride particles exhibit lower scattering loss, more stable optical properties, and multiple advantages such as anti-agglomeration, resistance to deterioration, and superior sintering and densification. The magnesium fluoride nanomaterials prepared by the method provided in this invention not only possess good sphericity but also exhibit good dispersibility without the need for surfactants, and have a relatively large average particle size (e.g., in some embodiments, the average particle size can reach over 200 nm).
[0018] A second aspect of the present invention provides a magnesium fluoride nanomaterial, which is prepared by any of the preparation methods described in the present invention.
[0019] In some embodiments, the average particle size of the magnesium fluoride nanomaterial is above 200 nm.
[0020] Compared with the prior art, the beneficial effects of the present invention are at least as follows: the preparation method provided by the present invention uses hydrofluoric acid as a fluorine source, which can produce magnesium fluoride nanomaterials with excellent sphericity and good dispersibility. Moreover, the preparation method has mild reaction conditions, is simple to operate, and is suitable for industrial production. In some preferred embodiments, by controlling the reaction conditions, magnesium fluoride nanomaterials with good sphericity, dispersibility, uniformity, and large particle size can be obtained. Attached Figure Description
[0021] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0022] Figure 1a These are macroscopic photographs of the magnesium fluoride nanomaterials prepared in Example 1;
[0023] Figure 1b This is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 1;
[0024] Figure 1c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 1;
[0025] Figure 1d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 1;
[0026] Figure 2a These are macroscopic photographs of the magnesium fluoride nanomaterials prepared in Example 2;
[0027] Figure 2bThis is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 2;
[0028] Figure 2c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 2;
[0029] Figure 2d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 2;
[0030] Figure 3a These are macroscopic photographs of the magnesium fluoride nanomaterials prepared in Example 3;
[0031] Figure 3b This is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 3;
[0032] Figure 3c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 3;
[0033] Figure 3d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 3;
[0034] Figure 4a These are macroscopic photographs of the magnesium fluoride nanomaterials prepared in Example 4;
[0035] Figure 4b This is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 4;
[0036] Figure 4c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 4;
[0037] Figure 4d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 4;
[0038] Figure 5a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 5;
[0039] Figure 5b This is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 5;
[0040] Figure 5c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 5;
[0041] Figure 5d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 5;
[0042] Figure 6a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 6;
[0043] Figure 6b This is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 6;
[0044] Figure 6c Here is a SEM image of the magnesium fluoride nanomaterials prepared in Example 6;
[0045] Figure 7 These are SEM comparison images of magnesium fluoride prepared in Example 1 and Comparative Examples 1-3;
[0046] Figure 8 These are XRD comparison images of magnesium fluoride prepared in Example 1 and Comparative Examples 1-3;
[0047] Figure 9 This is the XRD pattern of magnesium fluoride prepared by the hydrothermal reaction in Comparative Example 4.
[0048] Figure 10 This is a SEM image of magnesium chloride prepared in Comparative Example 4. Detailed Implementation
[0049] The invention will be more fully understood through the following detailed description, which should be read in conjunction with the accompanying drawings. Detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the specific functional details disclosed herein should not be construed as limiting, but rather as the basis for the claims and as intended to teach those skilled in the art to employ the representative basis of the invention in different ways in any suitable detailed embodiment.
[0050] In addition, unless otherwise specified, all raw materials used in the following embodiments can be purchased from the market or other sources, and all production and testing equipment used are known in the art, as are the testing methods used.
[0051] Example 1
[0052] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0053] The purified magnesium chloride aqueous solution was diluted to 0.16 mol / L, and a 2.4 mol / L hydrofluoric acid aqueous solution was prepared. The magnesium chloride aqueous solution was heated to 30°C, and the hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 4 ml / min, ensuring a molar ratio of hydrogen fluoride to magnesium chloride of 2:1. The reaction was started at 30°C and timed for 2 hours to obtain a suspension containing magnesium fluoride. After the reaction was completed, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed with deionized water. The product was dried in a vacuum oven at 55°C to obtain magnesium fluoride nanomaterials.
[0054] Figure 1aThis is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 1. It can be seen that the product is macroscopically a well-dispersed powder. Figure 1b The image shows the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 1. The XRD pattern of the product is in perfect agreement with the standard card 01-071-4795, with no impurity peaks. Figure 1c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 1. It can be seen that the microstructure exhibits well-dispersed spherical shapes with excellent sphericity, uniform particle size, and no agglomeration. Figure 1d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 1. It can be seen that the particle size distribution is uniform, with an average particle size of about 244.54 nm.
[0055] Example 2
[0056] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0057] The purified magnesium chloride aqueous solution was diluted to 0.16 mol / L, and a 2.4 mol / L hydrofluoric acid aqueous solution was prepared. The temperature of the magnesium chloride aqueous solution was kept constant at 10℃. The hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 2 ml / min, ensuring a hydrogen fluoride to magnesium chloride molar ratio of 2:1. The reaction was started at 10℃ and continued for 2 hours to obtain a suspension containing magnesium fluoride. After the reaction was complete, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed in deionized water. The product was dried in a vacuum oven at 55℃ to obtain magnesium fluoride nanomaterials.
[0058] Figure 2a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 2. Figure 2b The image shows the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 2. The XRD pattern of the product is in perfect agreement with the standard card 01-071-4795, with no impurity peaks. Figure 2c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 2. Figure 2d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 2, with an average particle size of approximately 79.23 nm.
[0059] Example 3
[0060] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0061] The purified magnesium chloride aqueous solution was diluted to 0.04 mol / L, and a 0.2 mol / L hydrofluoric acid aqueous solution was prepared. The magnesium chloride aqueous solution was heated to 70°C, and the hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 6 ml / min, ensuring a molar ratio of hydrogen fluoride to magnesium chloride of 2:1. The reaction was started at 70°C for 8 hours, yielding a suspension containing magnesium fluoride. After the reaction was completed, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed with deionized water. The product was dried in a vacuum oven at 55°C to obtain magnesium fluoride nanomaterials.
[0062] Figure 3a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 3. It can be seen that the product is macroscopically a well-dispersed powder. Figure 3b The image shows the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 3. It can be seen that the XRD pattern of the product is completely consistent with the standard card 01-071-4795, with no impurity peaks. Figure 3c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 3. It can be seen that the product has a certain spherical morphology, but compared with Example 1, the magnesium fluoride prepared in Example 3 tends to be a slightly flattened spherical shape. Figure 3d This is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 3, with an average particle size of 136.1 nm.
[0063] Example 4
[0064] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0065] The purified magnesium chloride aqueous solution was diluted to 0.4 mol / L, and a 0.2 mol / L hydrofluoric acid aqueous solution was prepared. The magnesium chloride aqueous solution was heated to 30°C, and the hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 8 ml / min, ensuring a molar ratio of hydrogen fluoride to magnesium chloride of 2:1. The reaction was started at 30°C and timed for 0.6 h, yielding a suspension containing magnesium fluoride. After the reaction was completed, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed with deionized water. The product was dried in a vacuum oven at 55°C to obtain magnesium fluoride nanomaterials.
[0066] Figure 4a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 4. It can be seen that the product is macroscopically a powder with good dispersibility. Figure 4b The image shows the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 4. It can be seen that the XRD pattern of the product is completely consistent with the standard card 01-071-4795, with no impurity peaks. Figure 4c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 4, showing that the product has a spherical microstructure. Figure 4dThis is a particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 4, with an average particle size of 76.45 nm.
[0067] Example 5
[0068] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0069] The purified magnesium chloride aqueous solution was diluted to 0.04 mol / L, and a 4.8 mol / L hydrofluoric acid aqueous solution was prepared. The magnesium chloride aqueous solution was heated to 40°C, and the hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 3 ml / min, ensuring a molar ratio of hydrogen fluoride to magnesium chloride of 2:1. The reaction was started at 40°C and timed for 9 h, yielding a suspension containing magnesium fluoride. After the reaction was completed, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed in deionized water, and the product was dried in a vacuum oven at 55°C to obtain magnesium fluoride.
[0070] Figure 5a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 5. It can be seen that the product is macroscopically a powder with good dispersibility. Figure 5b The image shows the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 5. It can be seen that the XRD pattern of the product is completely consistent with the standard card 01-071-4795, with no impurity peaks. Figure 5c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 5, showing that the product has a spherical microstructure. Figure 5d This is the particle size distribution diagram of the magnesium fluoride nanomaterials prepared in Example 5. The particles have good uniformity and an average particle size of 274.37 nm.
[0071] Example 6
[0072] This embodiment provides a magnesium fluoride nanomaterial and its preparation method, specifically including the following steps:
[0073] The purified magnesium chloride aqueous solution was diluted to 0.4 mol / L, and a 4.8 mol / L hydrofluoric acid aqueous solution was prepared. The magnesium chloride aqueous solution was heated to 50°C, and the hydrofluoric acid aqueous solution was added dropwise to the magnesium chloride aqueous solution at a rate of 15 ml / min, ensuring a molar ratio of hydrogen fluoride to magnesium chloride of 2:1. The reaction was started at 50°C for 4 hours, yielding a suspension containing magnesium fluoride. After the reaction was completed, the system was cooled, centrifuged, and washed 1-2 times with deionized water. The washed magnesium fluoride was dispersed with deionized water. The product was dried in a vacuum oven at 55°C to obtain magnesium fluoride nanomaterials.
[0074] Figure 6a This is a macroscopic photograph of the magnesium fluoride nanomaterials prepared in Example 6. Figure 6bThis is the XRD pattern of the magnesium fluoride nanomaterials prepared in Example 6. It can be seen that the XRD pattern of the product is completely consistent with the standard card 01-071-4795, with no impurity peaks. Figure 6c This is a SEM image of the magnesium fluoride nanomaterials prepared in Example 6, showing that the product has a spherical morphology.
[0075] Comparative Examples 1-3
[0076] The only difference between Comparative Examples 1-3 and Example 1 is that hydrofluoric acid was replaced with sodium fluoride, ammonium fluoride, and potassium fluoride of the same concentration as shown in Table 1. The rest of the procedures were the same as in Example 1 and will not be repeated here.
[0077] Table 1
[0078] Group Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Fluorine source hydrofluoric acid Sodium fluoride ammonium fluoride Potassium fluoride
[0079] Figure 7 Figure 1 shows a comparison of SEM images of magnesium fluoride prepared in Example 1 and Comparative Examples 1-3. In Figure 1, (a) is the magnesium fluoride prepared using hydrofluoric acid in Example 1, (b) is the magnesium fluoride prepared using sodium fluoride in Comparative Example 1, (c) is the magnesium fluoride prepared using ammonium fluoride in Comparative Example 2, and (d) is the magnesium fluoride prepared using potassium fluoride. The comparison shows that the magnesium fluoride prepared using hydrofluoric acid as the fluorine source has the best morphology and superior sphericity, while the magnesium fluoride prepared using other fluorine sources has a poorer morphology. Figure 8 These are XRD comparison diagrams of magnesium fluoride prepared in Example 1 and Comparative Examples 1-3. The comparison shows that although all of the above fluorine sources can produce rutile magnesium fluoride, the magnesium fluoride prepared by hydrofluoric acid in Example 1 has better crystallinity.
[0080] Comparative Example 4
[0081] The only difference between Comparative Example 4 and Example 1 is that in Comparative Example 4, hydrofluoric acid solution and magnesium chloride aqueous solution were mixed and then placed in a high-pressure reactor for hydrothermal reaction at 100°C for 2 hours. The rest of the process was the same as in Example 1 and will not be repeated here.
[0082] Figure 9 This is the XRD pattern of magnesium fluoride prepared by the hydrothermal reaction in Comparative Example 4. Figure 10 This is a SEM image of magnesium chloride prepared in Comparative Example 4. Comparing Example 1 and Comparative Example 4, it was found that, compared with the open reaction conditions used in this embodiment (the temperature was maintained by a water bath in the example), the magnesium chloride prepared by the hydrothermal reaction in Comparative Example 4 had poorer sphericity than that in Example 1, and the product showed adhesion and agglomeration.
[0083] In addition, the inventors of this case also conducted experiments with other raw materials, process operations, and process conditions described in this specification, referring to the aforementioned embodiments, and obtained relatively ideal results in all cases.
[0084] This invention provides a one-step method for synthesizing high-purity magnesium fluoride nanomaterials with good sphericity. Unlike existing methods that employ complex techniques such as special additives and external fields, this invention uses only hydrofluoric acid as the fluorine source and controls relevant reaction parameters to prepare spherical, well-dispersed, and uniformly sized magnesium fluoride nanomaterials through a direct precipitation synthesis process. In some embodiments, the particle diameter can reach over 200 nm. Furthermore, the byproduct of this reaction is hydrogen chloride, which, compared to byproducts such as ammonium chloride and sodium chloride produced in other fluorine source reactions, is less likely to introduce other metal cation impurities, thus ensuring product purity.
[0085] All aspects, embodiments, features, and examples of this invention should be considered illustrative and used to explain and illustrate the invention, but not to limit the invention. The scope of the invention is defined only by the claims.
[0086] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the described embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this invention is not intended to be limited to the specific embodiments disclosed for carrying out the invention, but rather is intended to encompass all embodiments falling within the scope of the appended claims.
Claims
1. A method for preparing a magnesium fluoride nanomaterial, characterized in that, include: Hydrofluoric acid solution was added to magnesium salt solution in batches, and the reaction was carried out at a temperature of 10~70℃ to obtain magnesium fluoride nanomaterials.
2. The method of claim 1, wherein: The concentration of hydrofluoric acid in the hydrofluoric acid solution is 0.2 mol / L to 4.8 mol / L.
3. The method for preparing magnesium fluoride nanomaterials according to claim 1, characterized in that: The concentration of magnesium salt in the magnesium salt solution is 0.04 mol / L to 0.4 mol / L.
4. The method for preparing magnesium fluoride nanomaterials according to claim 1, characterized in that: The amount of hydrofluoric acid solution added satisfies the following condition: the molar ratio of hydrogen fluoride to magnesium salt is 1.8:1 to 2.2:
1.
5. The method for preparing magnesium fluoride nanomaterials according to claim 1, characterized in that: The magnesium salt contained in the magnesium salt solution is magnesium chloride.
6. The method for preparing magnesium fluoride nanomaterials according to claim 1, characterized in that: The reaction time is 0.5h to 8h; And / or, add the hydrofluoric acid solution to the magnesium salt solution at a dropping rate of 2~15 ml / min.
7. The preparation method according to any one of claims 1-6, characterized in that: The reaction temperature is 20~40℃ and the reaction time is 1.5h~3h.
8. The method for preparing magnesium fluoride nanomaterials according to claim 1, characterized in that, Also includes: The magnesium fluoride suspension obtained from the reaction was subjected to solid-liquid separation, and the separated magnesium fluoride nanomaterials were washed and dried.
9. A magnesium fluoride nanomaterial, characterized in that: It is prepared by the method for preparing magnesium fluoride nanomaterials according to any one of claims 1-8.
10. The magnesium fluoride nanomaterial according to claim 9, characterized in that: The average particle size of the magnesium fluoride nanomaterial is above 200 nm.