A method for preparing an interface assembled silicon oxide-based hollow sheet structure material

Abstract

The application belongs to the technical field of nanometer material synthesis, and provides a preparation method of an interface-assembled hollow sheet structure silica-based material, which comprises the following steps: dispersing a sulfate aqueous solution and alcohol in an organic solvent containing an amphiphilic polymer to form a stable oil-water interface; then adding an ammonia source to generate an ammonium sulfate salt template at the oil-water interface and catalyze the hydrolysis and condensation of the subsequently added silicon source to coat the surface of the ammonium sulfate crystal; and finally removing the water-soluble salt template and small-particle impurities through centrifugal water washing and alcohol washing to obtain the hollow sheet structure silica nanometer material. The preparation method is simple and economical, and has good repeatability. The silica prepared by the application has a well-defined hollow sheet structure, and is expected to be applied in the biomedical field.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of nanomaterial synthesis, and particularly relates to a preparation method of an interface-assembled silicon oxide-based hollow sheet structure material. BACKGROUND

[0002] Silicon-based nanostructure materials are one of the most representative nanostructure materials in biomedical treatment applications. The emergence of new silicon-based nanostructure materials greatly helps the experimental exploration of clinical diagnosis and treatment. The silicon oxide-based hollow nano-sheet structure is a new type of silicon-based nanostructure material developed in recent years, has a unique planar structure, a large specific surface area, rich surface physical and chemical properties, ideal biodegradability and biocompatibility, can realize multifunctionalization, effectively load and deliver molecular drugs, and has wide biomedical applications in tumor treatment and antibiosis.

[0003] At present, the method for preparing the silicon oxide-based hollow nano-sheet structure still has bottlenecks such as expensive synthesis equipment and complicated synthesis steps, and scientists are still exploring the synthesis mechanism and rules of the silicon oxide-based nano-sheet structure material to optimize the synthesis methodology. Based on this, it has important theoretical significance and wide application prospect to deeply understand the influence of various reaction conditions and factors on the synthesis results, deeply study the molecular self-assembly process at the mesoscopic level, and explore and develop a general and simple synthesis route to prepare the silicon oxide-based hollow sheet structure material. Therefore, the application provides a preparation method of an interface-assembled silicon oxide-based hollow sheet structure material. SUMMARY

[0004] The application aims to provide a preparation method of an interface-assembled silicon oxide-based hollow sheet structure material, and aims to solve the problems in the background art.

[0005] To achieve the above-mentioned purpose, the application provides the following technical scheme.

[0006] A preparation method of an interface-assembled silicon oxide-based hollow sheet structure material, comprising the following steps:

[0007] Step 1) mixing an amphiphilic polymer and an organic solvent to obtain a clear and transparent solution;

[0008] Step 2) adding a sulfate aqueous solution and an alcohol into the mixed solution in step 1) to obtain a stable oil-water system;

[0009] Step 3) adding an ammonia source into the mixed solution in step 2) to generate ammonium sulfate crystals;

[0010] Step 4) adding a silicon source into the mixed solution in step 3), uniformly mixing, and then constant-temperature standing and reaction, so that the silicon oxide shell formed after hydrolysis and condensation of the silicon source is coated on the surface of the ammonium sulfate crystals;

[0011] Step 5) collecting the end product of step 4) to obtain the target product, the hollow sheet structure material of silicon oxide, after centrifugation, water washing, alcohol washing and drying.

[0012] Further, in step 1), the amphiphilic polymer is polyvinylpyrrolidone with a molecular weight of 10 kg / mol, 29 kg / mol, 40 kg / mol or 55 kg / mol.

[0013] Further, in step 1), the organic solvent is n-pentanol.

[0014] Further, in step 2), the aqueous sulfate solution is an aqueous iron sulfate solution with a concentration of 10-150 mg / mL.

[0015] Further, in step 2), the alcohol is 100-1500 μL of ethanol.

[0016] Further, in step 3), the ammonia source is 20-150 μL of ammonia water.

[0017] Further, in step 4), the silicon source is one of tetraethyl orthosilicate, 1,2-bis(triethoxysilyl)ethane and 3-aminopropyltriethoxysilane, with a dosage of 10-180 μL.

[0018] Further, the reaction temperature is 0-80℃, and the reaction time is 2-24 h.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] The method for preparing the interface-assembled hollow sheet structure material of silicon oxide is simple, economical and reproducible, and the silicon oxide prepared by the present application has a well-defined hollow sheet structure, and is expected to be applied in the field of biomedicine. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 Figure 1 is a schematic diagram of the synthesis method of the interface-assembled hollow sheet structure material of silicon oxide.

[0022] Figure 2 In the figure, (a) is a scanning electron microscope image of ammonium sulfate crystals; (b) is a scanning electron microscope image of silicon layer-coated ammonium sulfate crystals; (c) is a transmission electron microscope image of the hollow silicon sheet structure after the ammonium sulfate crystals are removed by water washing; and (d) is a transmission electron microscope image of the local magnification of the hollow silicon sheet structure.

[0023] Figure 3 In the figure, (a), (b) and (c) are scanning electron microscope images of samples prepared by different mixing methods; and (d) is a scanning electron microscope image of a sample prepared after the reaction system is enlarged by 50 times.

[0024] Figure 4 Scanning electron microscope images of samples prepared with different amounts of ethanol. Wherein, (a) is the amount of 100 μL ethanol; (b) is the amount of 1000 μL ethanol; (c) is the amount of 1500 μL ethanol; (d) is the amount of 2500 μL ethanol.

[0025] Figure 5 Scanning electron microscope images of samples prepared with different amounts of ammonia. Wherein, (a) is the amount of 20 μL ammonia; (b) is the amount of 30 μL ammonia; (c) is the amount of 150 μL ammonia; (d) is the amount of 200 μL ammonia.

[0026] Figure 6 Transmission electron microscope images of samples prepared by different silicon sources. Wherein, (a) is 1,2-bis(triethoxysilyl)ethane; (b) is 3-aminopropyl triethoxysilane.

[0027] Figure 7 Scanning electron microscope images of samples prepared at different reaction temperatures. Wherein, (a) is 4℃; (b) is 60℃; (c) is 80℃. Embodiment

[0028] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application, and are not used to limit the present application.

[0029] The specific implementation of the present application is described in detail below in combination with specific examples.

[0030] An embodiment of the present application provides a preparation method of an interface assembled silicon oxide-based hollow sheet structure material, comprising the following steps:

[0031] Step 1) mixing an amphiphilic polymer with an organic solvent to obtain a clear and transparent solution;

[0032] Step 2) adding a sulfate aqueous solution and an alcohol into the mixed solution of step 1) to obtain a stable oil-water system;

[0033] Step 3) adding an ammonia source into the mixed solution of step 2) to generate ammonium sulfate crystals;

[0034] Step 4) adding a silicon source into the mixed solution of step 3), uniformly mixing and then constant-temperature standing and reacting, and a silicon oxide shell layer formed after hydrolysis and condensation of the silicon source is coated on the surface of the ammonium sulfate crystals;

[0035] Step 5) collecting the final product of step 4), and after centrifugation, water washing, alcohol washing and drying, a target product, a silicon oxide hollow sheet structure material, is obtained.

[0036] In the embodiments of the present application, the preparation method comprises the following steps:

[0037] Step 1) ultrasonic stirring the amphiphilic polymer in the organic solvent until completely dissolved to obtain a clear and transparent solution;

[0038] Step 2) adding the aqueous sulfate solution and alcohol into the mixed solution of step 1) and gently stirring for 2 h to form a stable oil-water system;

[0039] Step 3) adding the ammonia source dropwise into the mixed solution of step 2), and the ammonium ions and sulfate ions are attracted to the polymer through electrostatic interaction to grow preferentially into cubic ammonium sulfate crystals under the crystal face selection of the amphiphilic polymer.

[0040] Step 4) adding the silicon source into the mixed solution of step 3) and gently stirring for 5 min, and then constant-temperature standing reaction, the silicon source is hydrolyzed into silicate oligomers when diffusing to the water-oil interface, and the negatively charged silicate oligomers are confined to the surface of the ammonium sulfate crystals through the coulomb interaction with the ammonium ions and polymerized into silicon oxide under the catalysis of residual ammonia molecules to form the silicon oxide coated on the surface of the ammonium sulfate crystals.

[0041] Step 5) collecting the final product of step 4), and removing the water-soluble ammonium sulfate salt crystal template by centrifugal water washing, and removing the reaction system mother liquor and small particle impurities by alcohol washing, and the obtained product is white powder after drying, which is the silicon oxide hollow sheet structure material.

[0042] As a preferred embodiment of the present application, in step 1), the amphiphilic polymer is polyvinylpyrrolidone with a molecular weight of 10 kg / mol, 29 kg / mol, 40 kg / mol or 55 kg / mol.

[0043] In the embodiments of the present application, preferably, the amphiphilic polymer functions to minimize the interfacial tension, stabilize the oil-water interface, and induce the generation of ammonium sulfate cubic salt crystals through crystal face selection, and the amphiphilic polymer is preferably polyvinylpyrrolidone with a molecular weight of 40 kg / mol.

[0044] As a preferred embodiment of the present application, in step 1), the organic solvent is n-pentanol.

[0045] In the embodiments of the present application, preferably, the organic solvent is used to construct the oil phase, which can be n-pentanol with a volume of 5 mL.

[0046] As a preferred embodiment of the present application, in step 2), the aqueous sulfate solution is an aqueous iron sulfate solution with a concentration of 10-150 mg / mL.

[0047] In the embodiment of the present application, preferably, the aqueous solution of sulfate is used to generate the salt template and the aqueous phase in the oil-water interface, which can be an aqueous solution of ferric sulfate with a concentration of 10-150 mg / mL. Preferably, 40 mg / mL.

[0048] As a preferred embodiment of the present application, in step 2), the alcohol is 100-1500 μL of ethanol.

[0049] In the embodiment of the present application, preferably, the alcohol is used to adjust the oil-water interfacial tension, which can be ethanol, and the amount is preferably 500 μL.

[0050] As a preferred embodiment of the present application, in step 3), the ammonia source is 20-150 μL of ammonia water.

[0051] In the embodiment of the present application, preferably, the ammonia source is used to generate the salt template and catalyze the polymerization of silicate oligomers, which can be ammonia water, and the amount is preferably 60 μL.

[0052] As a preferred embodiment of the present application, in step 4), the silicon source is one of tetraethyl orthosilicate, 1,2-bis(triethoxysilyl)ethane and 3-aminopropyl triethoxysilane with an amount of 10-180 μL.

[0053] In the embodiment of the present application, preferably, the silicon source can be one of tetraethyl orthosilicate, 1,2-bis(triethoxysilyl)ethane, 3-aminopropyl triethoxysilane and other inorganic and organic silicon sources, and the amount is preferably 50 μL.

[0054] As a preferred embodiment of the present application, the reaction temperature is 0-80℃, and the reaction time is 2-24 h.

[0055] In the embodiment of the present application, preferably, the reaction temperature is preferably 30℃, and the reaction time is preferably 4 h. Example 1

[0056] 500 mg of polyvinylpyrrolidone (Mw = 40000) was dispersed in 5 mL of n-pentanol and ultrasonically stirred until completely dissolved. Then 140 μL of an aqueous solution of ferric sulfate (40 mg mL −1 ), 500 μL of anhydrous ethanol was stirred for 2 h (500 rpm). Then 60 μL of ammonia water (27 wt%) and 50 μL of tetraethyl orthosilicate (98 wt%) were added and stirred for 5 min (500 rpm). The reaction was carried out at 30℃ for 4 h, and the ammonium sulfate salt crystal template and small particle impurities were removed by centrifugal water washing and alcohol washing, and the sample was dried in a 65℃ oven overnight to obtain a white powder, which was a hollow sheet structure of silicon oxide. Please refer to Figure 1 . Example 2

[0057] The ammonium sulfate cubic crystals and the sample of the hollow silica sheet structure material obtained in Example 1 were characterized by scanning electron microscopy and transmission electron microscopy, please see Figure 2 . As shown in (a) of Figure 2 , the ammonium sulfate crystals grow preferentially along the {110}, {010} planes, and the morphology is cubic. As shown in (b) of Figure 2 , the introduction of the silicon source can modulate the growth of the ammonium sulfate crystals, which is conducive to obtaining more uniform cubic samples. As shown in (c) of Figure 2 , the hollow silica sheet structure is obtained after the ammonium sulfate crystals are removed by water washing. Figure 2 The local magnified transmission electron microscopy image in (d) can observe the hollow structure. Example 3

[0058] Most of them are the same as in Example 1, except that the mixing method in this embodiment is adjusted to vortex and ultrasonic. Or the reaction system is enlarged by 50 times in proportion, please see Figure 3 . Using different mixing methods or enlarging the reaction system can obtain the target product. Example 4

[0059] Most of them are the same as in Example 1, except that the amount of ethanol in this embodiment is adjusted to 100-1500 μL. Please see Figure 4 . When the amount of ethanol is adjusted between 100-1500 μL, the target product can basically be obtained, please see Figure 4 (a), (b) and (c), when the amount of ethanol reaches 2500 μL, the product is mainly spherical, please see Figure 4 (d). Example 5

[0060] Most of them are the same as in Example 1, except that the amount of ammonia in this embodiment is adjusted to 20-150 μL. Please see Figure 5 . When the amount of ammonia is adjusted between 20-150 μL, the target product can basically be obtained, please see Figure 5 (a), (b) and (c), when the amount of ammonia reaches 200 μL, the product is mainly irregular particles, please see Figure 5 (d). Example 6

[0061] Most of them are the same as in Example 1, except that the silicon source in this embodiment is changed to 1,2-bis(triethoxysilane)ethane and 3-aminopropyl triethoxysilane. Please see Figure 6When 1,2-bis(triethoxysilyl)ethane and 3-aminopropyltriethoxysilane are used as the silicon source, the hollow lamellar structure material can still be obtained. Example 7

[0062] Compared with Example 1, most of them are the same, except that the reaction temperature in this example is adjusted to 0-80℃. See Figure 7 The target sample can be obtained under different reaction temperatures.

[0063] The above is only the preferred embodiment of the present application, it should be noted that for those skilled in the art, without departing from the concept of the present application, can also make several deformation and improvement, these should be considered as the protection scope of the present application, these will not affect the effect and the practicality of the patent of the present application.

Claims

1. A method for preparing an interfacial assembly of a silicon oxide-based hollow sheet-like structure material, characterized by, The method comprises the following steps: Step 1) mixing the amphiphilic polymer with an organic solvent to obtain a clear and transparent solution; Step 2) adding an aqueous sulfate solution and alcohol into the mixed solution of step 1) to obtain a stable oil-water system; Step 3) adding an ammonia source into the mixed solution of step 2) to generate ammonium sulfate crystals; Step 4) adding a silicon source into the mixed solution of step 3), uniformly mixing, and then constant-temperature standing and reaction, so that a silicon oxide shell layer formed after hydrolysis and condensation of the silicon source is coated on the surface of the ammonium sulfate crystals; Step 5) collecting the final product of step 4), and then obtaining the target product, a silicon oxide hollow sheet structure material, through centrifugation, water washing, alcohol washing and drying.

2. The method of claim 1, wherein the interface assembly of the silicon oxide-based hollow sheet structure material is prepared by the steps of: In step 1), the organic solvent is n-pentanol.

3. The method of claim 1, wherein the interface assembly of the silicon oxide-based hollow sheet structure material is prepared by the steps of: In step 2), the aqueous sulfate solution is an aqueous iron sulfate solution with a concentration of 10-150 mg / mL.

4. The method of claim 1, wherein the interface assembly of the silicon oxide-based hollow sheet structure material is prepared by the steps of: In step 2), the alcohol is 100-1500 μL of ethanol.

5. The method of claim 1, wherein the interface assembly of the silicon oxide-based hollow sheet structure material is prepared by the steps of: In step 3), the ammonia source is 20-150 μL of ammonia water.

6. The method of claim 1, wherein the interface assembly of the silicon oxide-based hollow sheet structure material is prepared by the steps of: In step 4), the silicon source is one of n-tetraethyl orthosilicate, 1,2-bis(triethoxysilane)ethane and 3-aminopropyl triethoxysilane, and the amount is 10-180 μL.

7. The method of claim 1-6, wherein the method is characterized by: The reaction temperature is 0-80 ℃, and the reaction time is 2-24 h.

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