Hollow nano silicon dioxide with multi-layer shell structure and preparation method of hollow nano silicon dioxide

Abstract

The invention provides hollow nano silicon dioxide with a multi-layer shell structure and a preparation method of the hollow nano silicon dioxide. The preparation method comprises the following steps: carrying out hydrolytic condensation on a raw material system comprising tetraalkoxysilane, a hydrophobic silane compound, a hydrophilic silane compound, an alcohol solvent and deionized water to obtain a precursor solution; dispersing the precursor solution in deionized water, stirring for self-assembly, adding alkali liquor to adjust pH, and performing curing reaction under alkali catalysis to obtain the hollow nano silicon dioxide with the multilayer shell structure. The hollow nano-silica with the multilayer shell structure prepared by the method provided by the invention has the advantages of good uniformity, controllable particle size and high porosity, and has wide application value and market potential in the fields of catalysis, energy storage, chemical separation, drug controlled release and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of silica nanomaterials, and particularly relates to hollow nanosilica with a multi-shell structure and a preparation method thereof. BACKGROUND

[0002] Compared with traditional hollow silica materials with a single-shell structure and solid silica materials, the hollow silica material with a multi-shell structure has greater specific surface area and reduced transmission path length of mass and charge, and thus has great application potential in the fields of catalysis, energy storage, chemical separation and drug controlled release.

[0003] At present, the hollow silica material with a multi-shell structure is mainly prepared by a particle self-assembly method and a sequential template method. For example, a Chinese patent application with the publication number CN 105000566 A discloses a method for synthesizing a hollow silica nanomaterial with a multi-shell structure and a multi-stage composite hole by a template method, which comprises the steps of preparing a hard template carbon sphere by a hydrothermal reaction and the steps of the hollow silica nanomaterial with a multi-shell structure and a multi-stage composite hole, and involves complex processes such as template synthesis, high-temperature calcination and the like. A Chinese patent application with the publication number CN 107673361 A discloses a preparation method of a hollow silica particle with a multi-shell structure, which needs to add an aqueous solution of a strong alkaline catalyst in alkyl silicate for multiple times, and each time needs to go through centrifugation, water washing and alcohol washing. After the preparation of the solid silica particle coated by “layer-by-layer”, the hollow silica particle with a multi-shell structure is obtained by steps such as heating incubation and centrifugal purification. The strong alkaline catalyst needs to be added for multiple times, and repeated centrifugation and washing are needed in the preparation process, which is complicated to operate. These methods are complicated in steps, harsh in preparation conditions, high in cost, low in efficiency and time-consuming, and are not conducive to scale production.

[0004] Therefore, it is an urgent problem to be solved to develop a preparation method of a hollow silica material with a multi-shell structure, which is efficient, low in cost and easy to scale. SUMMARY

[0005] The present application provides a preparation method of a hollow nanosilica with a multi-shell structure. The hollow nanosilica with a multi-shell structure prepared by the method has the advantages of good uniformity, controllable particle size and high porosity. The method does not need steps such as templates and high-temperature calcination, is simple in process, low in cost and conducive to scale production.

[0006] The present application also provides a hollow nanosilica with a multi-shell structure prepared by the above preparation method. The hollow nanosilica with a multi-shell structure has the advantages of good uniformity, controllable particle size and high porosity, and has wide application value and market potential in the fields of catalysis, energy storage, chemical separation and drug controlled release.

[0007] The first aspect of the present application provides a preparation method of hollow nanosilica with a multi-layer shell structure, characterized by comprising the following steps:

[0008] S1, hydrolysis and condensation of a raw material system comprising tetraalkoxysilane, hydrophobic silane compound, hydrophilic silane compound, alcohol solvent and deionized water to obtain a precursor solution;

[0009] S2, dispersing the precursor solution in deionized water and stirring for self-assembly, adding lye to adjust pH, and performing solidification reaction under alkali catalysis, collecting nanoparticles after centrifugation, and washing and drying to obtain the hollow nanosilica with a multi-layer shell structure.

[0010] The preparation method of hollow nanosilica with a multi-layer shell structure as described above, wherein the tetraalkoxysilane is at least one of tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane;

[0011] The hydrophobic silane compound is at least one of alkylsilane, vinylsilane, phenylsilane, acryloyloxysilane;

[0012] The hydrophilic silane compound is at least one of aminosilane, sulfonic silane, epoxy silane, diethylene glycol monomethyl ether silane, triethylene glycol monomethyl ether silane, polyethylene glycol monomethyl ether silane.

[0013] The preparation method of hollow nanosilica with a multi-layer shell structure as described above, wherein the tetraalkoxysilane is tetraethyl orthosilicate;

[0014] The hydrophobic silane compound is at least one of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane, and methacryloyloxypropyltriethoxysilane;

[0015] The hydrophilic silane compound is at least one of γ-glycidoxypropyltriethoxysilane, 3-aminopropyltriethoxysilane, and polyethylene glycol trimethoxysilane.

[0016] The preparation method of hollow nanosilica with a multi-layer shell structure as described above, wherein in step S1, the mass ratio of the tetraalkoxysilane to the hydrophobic silane compound is 1: (0.1-0.5);

[0017] The mass ratio of the tetraalkoxysilane to the hydrophilic silane compound is 1: (0.2-0.6).

[0018] The preparation method of hollow nanosilica with a multi-layer shell structure as described above, wherein in step S1, the hydrolysis and condensation is performed at 60-160°C for 4-12h.

[0019] The preparation method of the hollow nanosilica with a multi-layer shell structure as described above, in step S1, the alcohol solvent is at least one of methanol, ethanol, isopropanol, and butanol.

[0020] And / or, in step S1, the raw material system further comprises an inorganic acid; the inorganic acid is one of hydrochloric acid, nitric acid, and sulfuric acid.

[0021] The preparation method of the hollow nanosilica with a multi-layer shell structure as described above, in step S2, the mass ratio of the precursor solution to the water is 1: (2-10).

[0022] The preparation method of the hollow nanosilica with a multi-layer shell structure as described above, in step S2, the stirring condition is that stirring is performed at a speed of 300-1000 rpm at room temperature for 3-20 min.

[0023] And / or, in step S2, the solidification reaction is performed under the condition of 80-90℃ for 12-36h.

[0024] The preparation method of the hollow nanosilica with a multi-layer shell structure as described above, in step S2, the alkali solution is one of ammonia, sodium hydroxide solution, and potassium hydroxide solution; the pH range is 10-11.

[0025] The second aspect of the present application provides a hollow nanosilica with a multi-layer shell structure, which is prepared by the preparation method of the hollow nanosilica with a multi-layer shell structure.

[0026] The scheme of the present application has at least the following effects:

[0027] The preparation method of the hollow nanosilica with a multi-layer shell structure provided by the present application has the advantages of good uniformity, controllable particle size, and high porosity. The method does not require steps such as templates and high-temperature calcination, and has simple process and low cost, which is conducive to realizing large-scale production. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0029] Figure 1 The transmission electron microscope (TEM) image of the nanosilica in Example 1 of the present application;

[0030] Figure 2 Transmission electron microscope (TEM) image of the nanosilica in Example 2 of the present application;

[0031] Figure 3 Transmission electron microscope (TEM) image of the nanosilica in Example 3 of the present application;

[0032] Figure 4 Transmission electron microscope (TEM) image of the nanosilica in Example 4 of the present application;

[0033] Figure 5 Optical microscope image of the silica in Comparative Example 1 of the present application;

[0034] Figure 6 Transmission electron microscope (TEM) image of the silica in Comparative Example 2 of the present application;

[0035] Figure 7 SEM-EDS image of the nanosilica in Example 1 of the present application, wherein Figure 7 a is the EDS layered image of the nanosilica, Figure 7 b is the electron image of the nanosilica, Figure 7 c is the silicon (Si) element distribution map; Figure 7 d is the oxygen (O) element distribution map;

[0036] Figure 8 Total number spectrum of the distribution map of the nanosilica in Example 1 of the present application. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present application clearer, the following will combine the embodiments of the present application to make a clear and complete description of the technical solutions in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application. If the specific technology or condition is not mentioned in the embodiments, it is carried out according to the technology or condition described in the literature in the art or according to the product instruction. If the reagent or instrument is not mentioned by the manufacturer, it is a conventional product that can be obtained by market purchase.

[0038] In the following description, the term “and / or” is used to describe the association relationship of the associated objects, which means that there can be three kinds of relationships, for example, A and / or B, which can represent the following three cases: A exists alone, B exists alone and A and B exist simultaneously. Wherein A and B can be singular or plural.

[0039] Those skilled in the art shall understand that in the following description of the embodiments of the present application, the order of the serial numbers does not mean the order of execution, and part or all of the steps can be executed in parallel or in sequence, and the execution order of each process shall be determined according to its function and inherent logic, and shall not constitute any limitation on the implementation process of the embodiments of the present application.

[0040] Those skilled in the art shall understand that the numerical range in the embodiments of the present application shall be understood as also specifically disclosing each intermediate value between the upper limit and the lower limit of the range. Each smaller range between any stated value or intermediate value in a stated range and any other stated value or intermediate value in the stated range is also included in the present application. The upper limit and the lower limit of these smaller ranges can be independently included or excluded from the range.

[0041] Unless otherwise defined, technical / scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In the case of conflict between the content of this specification and any document incorporated herein by reference, the content of this specification prevails.

[0042] In a first aspect, the present application provides a preparation method of hollow nanosilica with a multi-layer shell structure, characterized in that the method comprises the following steps:

[0043] S1, hydrolysis and condensation of a raw material system comprising tetraalkoxysilane, hydrophobic silane compound, hydrophilic silane compound, alcohol solvent and deionized water to obtain a precursor solution;

[0044] S2, stirring and self-assembly of the precursor solution in deionized water, addition of lye to adjust pH, solidification reaction under alkali catalysis, collection of nanoparticles after centrifugation, washing and drying to obtain the hollow nanosilica with a multi-layer shell structure.

[0045] The hollow nanosilica with a multi-layer shell structure can be prepared by the above method. Specifically, a raw material system comprising tetraalkoxysilane, hydrophobic silane compound, hydrophilic silane compound and deionized water is uniformly mixed and then subjected to hydrolysis and condensation to obtain a precursor solution; the precursor solution is dispersed in deionized water and stirred for self-assembly to obtain a white emulsion; lye is added to the white emulsion to adjust pH, and after uniform mixing, a solidification reaction is carried out under alkali catalysis to obtain a reaction product; the reaction product is centrifuged to collect nanoparticles; the nanoparticles are washed and dried to obtain a white powder, i.e. the hollow nanosilica with a multi-layer shell structure.

[0046] In step S1, the possible principle of hydrolysis and condensation of the present application is described: firstly, under the action of an acid catalyst (in this application, an inorganic acid), the hydroxyl group in the water molecule replaces the alkoxy group in the silane to form a silanol, which is a reversible reaction; then a dehydration or dealcoholization condensation reaction occurs, i.e. a dehydration or dealcoholization between silanols or between silanols and alkoxy silanes to form a precursor containing a silicon-oxygen bond, and the precursor has a hydrophobic side chain and a hydrophilic segment.

[0047] In step S2, the possible principle of self-assembly of the present application is described: due to the amphiphilic nature of the precursor (containing a hydrophobic side chain and a hydrophilic segment), it can self-assemble in an aqueous phase; the hydrophilic group is usually responsible for stabilizing the surface of the self-assembled structure, preventing it from aggregating, while the hydrophobic group tends to aggregate to form hydrophobic micro-regions, and the synergistic effect of hydrophilic-hydrophobic allows the precursor to form a stable self-assembled structure in water.

[0048] In step S2, the addition of lye to adjust the pH is to accelerate the condensation reaction between silanols or between silanols and alkoxy silanes; the curing reaction is to cure the shell structure, which is conducive to the final formation of stable hollow nanosilica with a multi-layer shell structure.

[0049] The preparation method of hollow nanosilica with a multi-layer shell structure provided by the present application has the advantages of good uniformity, controllable particle size and high porosity; the method does not require steps such as templates and high-temperature calcination, and has a simple process and low cost, which is conducive to large-scale production.

[0050] In one specific embodiment, the tetraalkoxysilane is at least one of tetramethoxysilane, tetraethoxysilane, tetraisopropoxysilane, and the tetraalkoxysilane can be preferably tetraethyl orthosilicate.

[0051] In one specific embodiment, the hydrophobic silane compound is at least one of alkylsilane, vinylsilane, phenylsilane, acryloyloxy silane, and the hydrophobic silane compound can be preferably at least one of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane, and methacryloyloxypropyltriethoxysilane.

[0052] In one specific embodiment, the hydrophilic silane compound is at least one of aminosilane, sulfonic silane, epoxy silane, diethylene glycol monomethyl ether silane, triethylene glycol monomethyl ether silane, and polyethylene glycol monomethyl ether silane, and the hydrophilic silane compound can be preferably at least one of γ-glycidoxypropyltriethoxysilane, 3-aminopropyltriethoxysilane, and polyethylene glycol trimethoxysilylpropyl ether.

[0053] In an embodiment, in step S1, the mass ratio of the tetraalkoxysilane and the hydrophobic silane compound is 1: (0.1-0.5).

[0054] In an embodiment, in step S1, the mass ratio of the tetraalkoxysilane and the hydrophilic silane compound is 1: (0.2-0.6).

[0055] In step S1, if the mass of the hydrophilic silane compound is too high (for example, the mass ratio of the tetraalkoxysilane and the hydrophilic silane compound is 1:1), the precursor is prone to crosslinking after self-assembly; if the mass of the hydrophilic silane compound is too low (for example, the mass ratio of the tetraalkoxysilane and the hydrophilic silane compound is 1:0.05), the precursor is prone to form a silica with a single-layer shell structure after self-assembly.

[0056] In an embodiment, in step S1, the hydrolysis and condensation conditions are: reacting at 60-160°C for 4-12h.

[0057] In an embodiment, in step S1, the alcohol solvent is at least one of methanol, ethanol, isopropanol, and butanol.

[0058] In step S1, the raw material system further comprises an inorganic acid; the inorganic acid is one of hydrochloric acid, nitric acid, and sulfuric acid.

[0059] In an embodiment, in step S2, the mass ratio of the precursor solution and the water is 1: (2-10).

[0060] In an embodiment, in step S2, the stirring conditions are: stirring at a speed of 300-1000rpm at room temperature for 3-20min.

[0061] In an embodiment, in step S2, the solidification reaction conditions are: reacting at 80-90°C for 12-36h.

[0062] In an embodiment, in step S2, the alkali solution is one of aqueous ammonia, aqueous sodium hydroxide, and aqueous potassium hydroxide; the pH range is 10-11.

[0063] In an embodiment, in step S2, the centrifugation is: centrifuging at a speed of 10000-14000rpm for 15-40min.

[0064] In an embodiment, in step S2, the drying is: drying at 70-95°C until a constant weight is obtained.

[0065] In a second aspect, the present application provides a hollow nanosilica with a multi-layer shell structure, which is prepared by the method for preparing the hollow nanosilica with a multi-layer shell structure. The research of the present application shows that the hollow nanosilica with a multi-layer shell structure has the advantages of good uniformity, controllable particle size and high porosity, and has wide application value and market potential in the fields of catalysis, energy storage, chemical separation and drug controlled release.

[0066] The present application will be further described below through specific examples.

[0067] Example 1

[0068] The present example provides a method for preparing nanosilica, which comprises the following steps:

[0069] (1) 208 g of tetraethyl orthosilicate, 20 g of phenyltriethoxysilane, 80 g of γ-glycidoxypropyltriethoxysilane and 50 g of ethanol are uniformly mixed, 10 g of 37% mass fraction hydrochloric acid and 5 g of deionized water are uniformly mixed after stirring for 5 min, and the mixture is reacted at 80°C for 12 h. After the reaction is completed, vacuum distillation is carried out at a vacuum degree of 0.03 MPa for 1 h to remove the solvent, and a precursor solution is obtained;

[0070] (2) 40 g of the precursor solution is dispersed in 200 g of deionized water, and self-assembly is carried out at room temperature with stirring at a speed of 600 rpm for 5 min to obtain a white emulsion;

[0071] (3) 10 mL of 28% mass fraction ammonia water is added to the white emulsion to adjust the pH to 10.5, and the mixture is uniformly stirred at room temperature and reacted at 80°C for 24 h to obtain a reaction product;

[0072] (4) The reaction product is centrifuged at a speed of 12000 rpm for 30 min, and the nanoparticles are collected;

[0073] (5) The nanoparticles are washed twice with deionized water and once with ethanol, and then dried in an oven at 60°C to a constant weight to obtain a white powder, which is nanosilica.

[0074] Example 2

[0075] The method for preparing nanosilica provided in the present example is basically the same as that in Example 1, except that in step (1), 208 g of tetraethyl orthosilicate, 20 g of phenyltriethoxysilane, 80 g of γ-glycidoxypropyltriethoxysilane and 50 g of ethanol are uniformly mixed instead of 208 g of tetraethyl orthosilicate, 20 g of phenyltriethoxysilane, 50 g of polyethylene glycol trimethoxysilane propyl ether and 50 g of ethanol.

[0076] Example 3

[0077] The preparation method of the nanometer silicon dioxide provided in this example is basically the same as that in Example 1, except that in step (2), 200 g of deionized water is replaced by 100 g of deionized water, and in step (3), 10 mL of 28% ammonia water is replaced by 5 mL of 28% ammonia water.

[0078] Example 4

[0079] The preparation method of the nanometer silicon dioxide provided in this example is basically the same as that in Example 1, except that in step (1), 0.03 MPa vacuum degree is replaced by 0.02 MPa vacuum degree, in step (2), 200 g of deionized water is replaced by 100 g of deionized water, and in step (3), 10 mL of 28% ammonia water is replaced by 5 mL of 28% ammonia water.

[0080] Comparative Example 1

[0081] The preparation method of the nanometer silicon dioxide provided in this example is basically the same as that in Example 1, except that in step (1), 0.03 MPa vacuum degree is replaced by 0.02 MPa vacuum degree, in step (2), 200 g of deionized water is replaced by 100 g of deionized water, and in step (3), 10 mL of 28% ammonia water is replaced by 5 mL of 28% ammonia water.

[0082] (1) 208 g of tetraethyl orthosilicate, 20 g of phenyltriethoxysilane and 50 g of ethanol were mixed uniformly, 10 g of 37% hydrochloric acid and 5 g of deionized water were added after stirring for 5 min, and the mixture was reacted at 80°C for 12 h. After the reaction was completed, vacuum distillation was carried out at 0.03 MPa vacuum degree for 1 h to remove the solvent, and a precursor solution was obtained;

[0083] (2) 40 g of the precursor solution was dispersed in 200 g of deionized water, and self-assembly was carried out at room temperature with stirring at a speed of 600 rpm for 5 min to obtain an emulsion;

[0084] (3) 10 mL of 28% ammonia water was added to the white emulsion to adjust the pH to 10.5, and the mixture was stirred uniformly at room temperature and reacted at 80°C for 24 h to obtain a reaction product;

[0085] (4) The reaction product was centrifuged at a speed of 12000 rpm for 30 min, and the collected product was collected;

[0086] (5) The product was washed twice with deionized water and once with ethanol, and then dried in an oven at 60°C to constant weight to obtain silicon dioxide.

[0087] Comparative Example 2

[0088] The preparation method of the silica provided by the present comparative example is basically the same as that of Example 1, except that in step (2), 40 g of the precursor solution is replaced by 10 g of the precursor solution.

[0089] Performance test

[0090] 1. The nanosilica in Examples 1-4 and the silica in Comparative Examples 1-2 of the present application were subjected to microscope test, and the results are shown in Figures 1-6 Figure 1 It is a transmission electron microscope (TEM) image of the nanosilica in Example 1 of the present application; Figure 2 It is a transmission electron microscope (TEM) image of the nanosilica in Example 2 of the present application; Figure 3 It is a transmission electron microscope (TEM) image of the nanosilica in Example 3 of the present application; Figure 4 It is a transmission electron microscope (TEM) image of the nanosilica in Example 4 of the present application; Figure 5 It is an optical microscope image of the silica in Comparative Example 1 of the present application; Figure 6 It is a transmission electron microscope (TEM) image of the silica in Comparative Example 2 of the present application.

[0091] As can be seen from Figures 1-4 , the morphology of the nanosilica prepared by the method provided by the present application is a hollow microspherical structure with a multi-layer shell structure.

[0092] As can be seen from Figure 5 , the morphology of the silica in Comparative Example 1 is a fragment shape.

[0093] As can be seen from Figure 6 , the morphology of the silica in Comparative Example 2 is a hollow microspherical structure with a single-layer shell structure.

[0094] 2. The nanosilica in Example 1 of the present application was subjected to SEM-EDS analysis and distribution map total spectrum analysis, and the results are shown in Figure 7 and Figure 8 .

[0095] As can be seen from Figure 7 and Figure 8 , the silica is successfully prepared by the method provided by the present application.

[0096] 3. The nanosilica in Examples 1-4 and the silica in Comparative Examples 1-2 of the present application were subjected to the following tests as samples, and the test results are shown in Table 1.

[0097] The wall thickness of the outermost shell: obtained according to the above microscope test;

[0098] Particle size: the particle size of the sample was tested by dynamic light scattering method;​

[0099] PDI: PDI of the sample was tested by dynamic light scattering method;

[0100] Porosity: Porosity was calculated according to the wall thickness data combined with the particle size data, and the porosity calculation formula was as follows:

[0101] Porosity (%) = (1-2h / D) 3 ×100%

[0102] In the formula, h was the wall thickness, and D was the particle size.

[0103] Table 1 Test results of each example and comparative example

[0104]

[0105] As shown in Table 1, the hollow microspherical nanosilica with a multilayer shell structure can be prepared by the method provided in the embodiments of the present application, and the nanosilica has the advantages of good uniformity, controllable particle size, and high porosity, and has wide application value and market potential in the fields of catalysis, energy storage, chemical separation, and drug controlled release.

[0106] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for preparing hollow nano-silica with a multi-layered shell structure, characterized in that, Includes the following steps: S1. A raw material system comprising tetraalkoxysilane, hydrophobic silane compound, hydrophilic silane compound, alcohol solvent and deionized water is subjected to hydrolysis and condensation to obtain a precursor solution; S2. The precursor solution is dispersed in deionized water and stirred to perform self-assembly. Alkali solution is added to adjust the pH, and a solidification reaction is carried out under alkaline catalysis. After centrifugation, the nanoparticles are collected, washed, and dried to obtain the hollow nano-silica with a multi-layer shell structure.

2. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, The tetraalkoxysilane is at least one of tetramethoxysilane, tetraethoxysilane, and tetraisopropoxysilane; The hydrophobic silane compound is at least one of alkylsilane, vinylsilane, phenylsilane, and acryloyloxysilane; The hydrophilic silane compound is at least one of aminosilane, sulfonic acid silane, epoxy silane, diethylene glycol monomethyl ether silane, triethylene glycol monomethyl ether silane, and polyethylene glycol monomethyl ether silane.

3. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 2, characterized in that, The tetraalkoxysilane is tetraethyl orthosilicate; The hydrophobic silane compound is at least one of phenyltriethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane, and methacryloxypropyltriethoxysilane; The hydrophilic silane compound is at least one of γ-glycidoxypropyltriethoxysilane, 3-aminopropyltriethoxysilane, and polyethylene glycol trimethoxysilylpropyl ether.

4. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S1, the mass ratio of the tetraalkoxysilane to the hydrophobic silane compound is 1:(0.1-0.5). The mass ratio of the tetraalkoxysilane to the hydrophilic silane compound is 1:(0.2-0.6).

5. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S1, the conditions for hydrolysis and condensation are: reaction at 60-160℃ for 4-12 hours.

6. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S1, the alcohol solvent is at least one selected from methanol, ethanol, isopropanol, and butanol. And / or, in step S1, the raw material system further includes an inorganic acid; the inorganic acid is one of hydrochloric acid, nitric acid, and sulfuric acid.

7. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S2, the mass ratio of the precursor solution to the water is 1:(2-10).

8. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S2, the stirring conditions are: stirring at 300-1000 rpm for 3-20 minutes at room temperature; And / or, in step S2, the conditions for the curing reaction are: reacting at 80-90°C for 12-36 hours.

9. The method for preparing hollow nano-silica with a multi-layered shell structure according to claim 1, characterized in that, In step S2, the alkaline solution is one of ammonia water, sodium hydroxide aqueous solution, and potassium hydroxide aqueous solution; the pH range is 10-11.

10. A hollow nano-silica with a multi-layered shell structure, characterized in that, It is prepared by the method for preparing hollow nano-silica with a multi-layer shell structure as described in any one of claims 1-9.

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