CN113753904B - A kind of porous silicon dioxide nano ring and preparation method thereof - Google Patents

Abstract

The invention discloses a porous silicon dioxide nanoring and a preparation method thereof. The preparation method has the advantages of simple process, low cost and mild reaction conditions, can realize the controllable preparation of the porous silicon dioxide nanoring, and can be popularized for industrial production.

Description

A kind of porous silicon dioxide nano ring and preparation method thereof

technical field

The invention belongs to the technical field of nano-silicon compounds, and in particular relates to a method for preparing a porous silicon dioxide nano-ring, and further relates to a porous silicon dioxide nano-ring prepared by the preparation method.

Background technique

Nano-silica materials have been widely used in the fields of optics, electronics, biomedicine, bioseparation technology, biosensing technology, and catalytic reactions, and their shapes are various, such as nanospheres, nanosheets, etc., and different shapes Nano-silica often has different properties, especially some nanostructures with special shapes.

Due to its large specific surface area and strong adsorption capacity, nano-ring silica can be widely used in catalyst carriers, drug carriers and other fields. However, due to the special morphology of nanorings and the absence of suitable ring precursors, porous silica nanorings cannot be simply synthesized by chemical methods.

Existing silica nanorings are mainly prepared by the template method: one is to disperse the synthesized silica hollow spheres on a plane to form an array, and then perform ion etching to prepare nanoannular silica, but this method Need ion etching auxiliary means, and the yield is low (ACS Appl. The mechanical properties of the nanorings prepared by this method are not strong, and the requirements for experimental parameters are high, so it is not suitable for regulation, and it is not easy for industrial production (Langmuir 2018, 34, 26, 7751–7758).

Contents of the invention

In view of this, it is necessary for the present invention to provide a method for preparing porous silica nanorings, using a cationic surfactant as a template, and using a first shape control agent and a second shape control agent to regulate the growth direction of silicon dioxide , so as to prepare porous silicon dioxide nano rings. The preparation method has simple process, low cost and mild reaction conditions, and can be popularized for industrial production.

In order to achieve the above object, the present invention adopts the following technical solutions:

The invention provides a kind of preparation method of porous silicon dioxide nanoring, comprises the following steps:

Prepare a template solution, the template solution is an aqueous solution of cationic surfactant;

providing a first morphology control agent, fully mixing it with the template solution, and adjusting the pH value of the system to 2-13 to obtain a first micelle solution with lamellar micelles;

providing a second shape control agent, fully mixing it with the first micellar solution to obtain a second micellar solution with ring-shaped micelles;

Provide a silicon dioxide precursor, mix it with the second micellar solution, and heat up to react to obtain a porous silicon dioxide nanoring dispersion;

The porous silica nanoring dispersion is purified to obtain porous silica nanorings.

In a further scheme, in the template solution, the cationic surfactant is added in an amount of 0.25-2.5wt%;

The cationic surfactant is selected from cationic emulsifiers.

In a further scheme, the cationic emulsifier is selected from one of alkyl quaternary ammonium salts, heteroatom-containing quaternary ammonium salts, benzene ring-containing quaternary ammonium salts, heterocyclic quaternary ammonium salts, and amine salt cationic emulsifiers .

In a further solution, the first shape control agent is selected from one of water-soluble salts, water-soluble organic acids, anionic emulsifiers, and anionic polymers, wherein the water-soluble salt contains ClO ₄ ^- , Cl ^- , NO ₃ ^- , SO ₄ ^2- or SO ₃ ^2- , the water-soluble organic acid contains carboxylic acid, sulfonic acid, sulfinic acid or thiocarboxylic acid functional group.

In a further scheme, the anionic emulsifier is selected from one of carboxylate, sulfonate, and sulfate;

The anionic polymer is selected from one of sodium polyacrylate, sodium polymethacrylate, sodium polystyrene sulfonate, anionic water-based polyurethane, and anionic polyacrylamide.

In a further scheme, the pH range of the system is 8-11.

In a further scheme, the second shape control agent is an alcohol substance, and its dosage is 3-30wt%;

The alcohols are selected from at least one of ethanol, ethylene glycol, glycerol, diethylene glycol, hydroxyl-containing hydrophilic macromolecules, and hydroxyl-containing hydrophilic small molecules.

In a further solution, the silicon dioxide precursor is selected from one or a mixture of two or more of sodium silicate, methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, and a silane coupling agent.

In a further scheme, the specific steps of the temperature rise reaction are: stirring the reaction at 20-85° C. for 1-36 hours.

The present invention further provides a porous silica nanoring, which is prepared by the preparation method described in any one of the foregoing, wherein the porous silica nanoring is a porous ring with an inner diameter of 20-5000nm and an outer diameter of 500nm-10μm .

Compared with the prior art, the present invention has the following beneficial effects:

The preparation method of porous silica nanorings in the present invention uses cationic surfactants as templates, adopts the first shape control agent and the second shape control agent, regulates the growth of silicon dioxide in the template solution, and can directly induce Generation of porous silica nanorings.

The raw materials used are all commercial chemical reagents, which can be directly obtained from the market, and the cost is low; the preparation is carried out through a simple chemical reaction, and the process is simple; the reaction can be carried out at room temperature, the reaction condition is mild, and the industrial production is easy to realize.

In addition, the morphology of porous silica nanorings can be regulated by adjusting the amount of silica precursor, cationic surfactant and morphology control agent, and the regulation method is simple.

The obtained porous silica nanorings can be widely used in the fields of catalyst carrier, drug carrier, microwave absorption or sensor energy, and have broad prospects.

Description of drawings

Fig. 1 is a block diagram of the preparation method of porous silica nanorings in a preferred embodiment of the present invention;

Fig. 2 is the TEM figure of the porous silica nanoring of gained of embodiment 1 of the present invention;

Fig. 3 is the SEM picture of the porous silica nanoring of the embodiment of the present invention 1 gained;

Fig. 4 is the infrared spectrogram of the porous silica nano-rings obtained in Example 1 of the present invention;

Fig. 5 is the particle size distribution diagram of the porous silica nanorings obtained in Example 2 of the present invention;

Fig. 6 is the SEM picture of the porous silica nanoring of the embodiment of the present invention 2 gained;

Fig. 7 is the SEM figure of the porous silica nanoring that the embodiment of the present invention 3 gains;

Fig. 8 is the SEM figure of the porous silica nanoring of the embodiment 4 of the present invention gained;

Fig. 9 is an SEM image of the porous silica nanorings obtained in Example 5 of the present invention.

Detailed ways

In order to facilitate understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be embodied in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field of the invention. The terminology used herein in the description of the present invention is only for the purpose of describing specific embodiments, and is not intended to limit the present invention.

The first aspect of the present invention discloses a preparation method of porous silica nanorings, specifically as shown in Figure 1, comprising the following steps:

Prepare a template solution, the template solution is an aqueous solution of cationic surfactant;

providing a first morphology control agent, fully mixing it with the template solution, and adjusting the pH of the system to 2-13 to obtain a first micelle solution with lamellar micelles;

providing a second shape control agent, fully mixing it with the first micellar solution to obtain a second micellar solution with ring-shaped micelles;

Provide a silicon dioxide precursor, mix it with the second micellar solution, and heat up to react to obtain a porous silicon dioxide nanoring dispersion;

The porous silica nanoring dispersion is purified to obtain porous silica nanorings.

In the present invention, the cationic surfactant is used as a template, and the growth method of silicon dioxide is regulated in the template solution by the first shape control agent and the second shape control agent, and the silicon dioxide precursor is directly induced to make porous silicon dioxide. nano ring. Wherein, the preparation of the template solution is not particularly limited, and can be obtained by dissolving a cationic surfactant in deionized water.

The raw materials used in the preparation method are all commercial chemical reagents, which are easy to obtain and low in cost, and the whole preparation process has simple steps and mild reaction conditions.

In addition, in this preparation method, the morphology and size of the nanorings can be adjusted by adjusting the amount or ratio of the cationic surfactant, the first shape control agent, the second shape control agent, and the silica precursor. There is no particular limitation. Specifically, the size of the silica nanoring can be increased by increasing the amount of cationic surfactant and morphology control agent; the thickness of the ring wall can be increased by increasing the amount of the precursor of silicon dioxide. In one or more embodiments of the present invention, the amount of the cationic surfactant is 0.25-2.5wt%, the amount of the first shape control agent is 0.1-1.0wt%, and the amount of the second shape control agent is 3-30wt%. %, the amount of silicon dioxide precursor is 1-10wt%, and the aforementioned amounts are all measured based on the amount of deionized water in the template solution.

cationic surfactant

The cationic surfactants described herein refer to nitrogen-containing organic amine derivatives, specifically cationic emulsifiers, which are generally conventional raw materials for preparing nano-silica by the cationic active agent template method, without special limitations, and can be selected From alkyl quaternary ammonium salts, quaternary ammonium salts containing heteroatoms (such as oxygen atoms, sulfur atoms, nitrogen atoms), quaternary ammonium salts containing benzene rings, quaternary ammonium salts containing heterocyclic rings, and amine salt cationic emulsifiers One, of which, examples of alkyl quaternary ammonium salts that may be mentioned are dodecyltrimethylammonium bromide, cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride, containing Examples that may be mentioned of quaternary ammonium salts containing heteroatoms are cetyl hydroxypropyl dimethyl ammonium chloride, and examples of quaternary ammonium salts containing benzene rings are octadecyl dimethyl benzyl chloride Ammonium, dodecyldimethylbenzyl ammonium chloride, quaternary ammonium salts containing heterocyclic rings may be mentioned as cetylpyridinium bromide, cationic emulsifiers of the amine salt type may be mentioned as abietamine , it can be understood that the cationic surfactants in the present invention include but not limited to the above-mentioned several.

first shape control agent

The first shape-controlling agent described herein acts to interact with cationic surfactants to form lamellar micelles to regulate the growth direction of silicon dioxide. Therefore, the chemical composition of the first shape-controlling agent The structure should contain at least one functional group capable of interacting with the cationic surfactant to form a lamellar micelle compound, which can be adjusted according to the type of the cationic surfactant. In one or more embodiments of the present invention, the first shape control agent is selected from one of water-soluble salts, water-soluble organic acids, anionic emulsifiers, and anionic polymers. Wherein, the water-soluble salt contains ClO ₄ ^- , Cl ^- , NO ₃ ^- , SO ₄ ^2- or SO ₃ ^2- , and specific examples thereof include sodium sulfate, potassium sulfite or ammonium chloride; Water-soluble organic acid is the organic acid that contains carboxylic acid, sulfonic acid, sulfinic acid or thiocarboxylic acid functional group and has certain solubility in water, and the specific examples that can be mentioned have vanillic acid, citric acid; The anionic emulsifier One selected from carboxylate type, sulfonate type, and sulfate type, wherein the carboxylate type can be sodium oleate, the sulfonate type can be sodium hexadecylsulfonate, and the sulfate type can be It is sodium lauryl sulfate; the anionic polymer is selected from one of sodium polyacrylate, sodium polymethacrylate, sodium polystyrene sulfonate, anionic water-based polyurethane, and anionic polyacrylamide.

second shape control agent

The role of the second morphology-controlling agent described herein is to dissociate the less-curvature parts of the micelles, thereby converting lamellar micelles to annular micelles. Therefore, the second morphology control agent is a compound containing -OH functional group. Since the -OH functional group is hydrophilic, it can interact with the cationic surfactant to dissociate the small curvature part of the micelle. Specific examples that can be mentioned include but are not limited to ethanol, ethylene glycol, glycerol, diethylene glycol, hydroxyl-containing hydrophilic polymers, and a mixture of two or more of hydrophilic small molecules; preferably Yes, considering the availability and cost of raw materials, the second shape control agent is selected from at least one of ethanol and ethylene glycol. This is mainly because ethanol and ethylene glycol have simple structures and are easy to remove later.

Silica Precursor

The silicon dioxide precursor described herein can obtain silicon dioxide through processes such as hydrolysis and condensation, which are not particularly limited and can be conventional choices in this field. Specific examples that can be mentioned include but are not limited to sodium silicate , methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, one or a mixture of two or more of silane coupling agents.

In a further scheme, the reaction in the present invention can be carried out under acidic or alkaline conditions, but generally speaking, since the pH value can affect the hydrolysis and polycondensation reaction rate of the silica precursor, it is preferred that in the preparation method , adjust the system to be alkaline, more preferably, its pH range is 8-11, so as to obtain a better rate of hydrolysis polycondensation reaction. The step of adjusting the pH can be done by adding lye conventionally in the art. In one or more embodiments of the present invention, the specific steps are to add an organic base or an inorganic base to the system until the pH is 8-11, and then stir 3-24h, wherein, the specific examples of the organic base include but not limited to ethylenediamine, triethylamine, triethanolamine, tetraethylenepentamine, diethylenetriamine, triethylenetetramine, ammonia water, trihydroxy One of methylaminomethane, tetrahydroxyethylethylenediamine, tetrahydroxypropylethylenediamine, tetraethylethylenediamine, 1,8-bisdimethylaminonaphthalene, and imidazole, and the inorganic base can specifically be Examples mentioned include, but are not limited to, one of ammonia water, sodium hydroxide, and potassium hydroxide.

In a further scheme, after adding the silicon dioxide precursor, a temperature rise reaction is carried out so that the silicon dioxide precursor is hydrolyzed and condensed, and the reaction rate can be adjusted by adjusting the reaction temperature, and the specific reaction time can be determined according to the added silicon dioxide precursor. In one or more embodiments of the present invention, the specific steps of the temperature rise reaction are: stir the reaction at 20-85°C for 1-36h, preferably, the reaction temperature is 20 -65°C, more preferably 30-50°C.

The second aspect of the present invention provides a porous silica nanoring, which is prepared by the preparation method as described in the first aspect of the present invention. By adjusting the amount and proportion of raw materials, the porous silica nanoring can be realized. Morphology and size control, in one or more embodiments of the present invention, the porous silica nanoring is a porous ring with an inner diameter of 20-5000nm and an outer diameter of 500nm-10μm, that is, the silica is ring-shaped structure, and a multi-channel structure is formed on the ring. The nanoporous ring has a special shape and can be widely used in the fields of catalyst carrier, drug carrier, microwave absorption, sensor and the like.

The technical solutions of the present invention will be described more clearly and completely below in conjunction with specific embodiments.

Example 1

Weigh 0.5g cetyltrimethylammonium bromide and add it to 200mL deionized water to dissolve, and stir mechanically for 3h to form a uniform template solution;

Add 0.2 g of sodium polyacrylate to the template solution, adjust the pH of the system to 8 with ammonia water, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 40 mL of ethanol to the first micelle solution and stir for 10 min, then add 2 g of tetraethyl orthosilicate, heat up to 40° C. and stir for 12 h to obtain a porous silica nanoring dispersion;

The porous silicon dioxide nano-ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano-ring.

Example 2

Weigh 1.0g of cetyltrimethylammonium chloride and add it to 200mL of deionized water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 0.5 g of sodium lauryl sulfate to the template solution, adjust the pH to 9 with triethylamine, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 40mL of ethylene glycol to the first micellar solution and stir for 5min, then add 4g of methyl orthosilicate, heat up to 20°C and stir for 12h to obtain a porous silica nanoring dispersion;

The porous silicon dioxide nano-ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano-ring.

Example 3

Weigh 1.5g of dodecyldimethylbenzyl ammonium chloride and add it to 200mL of deionized water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 1.0 g of anionic polyacrylamide to the template solution, adjust the pH to 9 with ammonia water, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 20mL of ethanol to the first micelle solution and stir for 10min, then add 6g of sodium silicate, heat up to 60°C and stir for 12h to obtain a porous silica nanoring dispersion;

The porous silicon dioxide nano ring dispersion is purified and freeze-dried to obtain the porous silicon dioxide nano ring.

Example 4

Weigh 1.0g of cetyltrimethylammonium chloride and add it to 200mL of distilled water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 2.5 g of sodium lauryl sulfate to the template solution, adjust the pH to 10 with triethanolamine, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 60 mL of ethylene glycol to the first micelle solution and stir for 10 min, then add 10 g of 3-aminopropyltriethoxysilane, heat up to 65°C and stir for 1 h to obtain a porous silica nanoring dispersion;

The obtained porous silicon dioxide nano ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano ring.

Example 5

Weigh 5.0g of dodecyltrimethylammonium chloride and add to 200mL of deionized water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 2.0 g of sodium polystyrene sulfonate to the template solution, adjust the pH to 11 with sodium hydroxide, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 5 mL of ethanol to the first micelle solution and stir for 10 min, then add 20 g of tetraethyl orthosilicate, heat up to 60° C. and stir for 36 h to obtain a porous silica nanoring dispersion;

The porous silica nano-ring dispersion is purified and spray-dried to obtain the porous silica nano-ring.

Example 6

Weigh 5.0g of dodecyltrimethylammonium chloride and add to 200mL of deionized water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 2.0 g of sodium polystyrene sulfonate to the template solution, adjust the pH to 11 with sodium hydroxide, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 80ml of ethanol to the first micelle solution and stir for 1h, then add 20g of ethyl orthosilicate, heat up to 40°C and stir for 10h to obtain a porous silica nanoring dispersion;

The porous silicon dioxide nano-ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano-ring.

test case

The porous silica nanorings prepared in Examples 1-6 were respectively characterized, and the test results are shown in the accompanying drawings.

Wherein, Fig. 2 is the TEM picture of the porous silica nanoring in embodiment 1, as can be seen from the figure, silica is a porous structure, and the morphology is ring-shaped, and the ring width of the nanoring is about 70nm;

Fig. 3 is the SEM picture of the porous silica nano-ring in embodiment 1, as can be seen from the figure, the silica morphology is ring-shaped;

Fig. 4 is the infrared spectrogram of the porous silica nanoring powder in embodiment 1, wherein, the absorption peak at 3419cm ^-1 place is -OH stretching vibration peak and bending vibration peak, the strong absorption peak at 1063cm ^-1 place is The characteristic absorption peak attributed to the porous silica nanoring caused by the vibration of Si-O-Si indicates that the nanoporous silica nanoring was successfully synthesized in this example.

Fig. 5 is the particle size distribution figure of the porous silica nano-ring in embodiment 2, because the appearance of nano-ring is special, can obtain the ring width and the information of distribution situation of porous silica nano-ring from the result, by Fig. It can be seen that the ring width peak of the porous silica nanoring is at 72nm, and the average ring width is about 75nm;

FIG. 6 is an SEM image of the porous silica nanoring in Example 2. It can be seen from the figure that the silica has a ring shape.

Fig. 7, Fig. 8, Fig. 9 are divided into the SEM figure of the porous silica nanoring in embodiment 3, embodiment 4 and embodiment 5, as can be seen from the figure, silica morphology is all ring-shaped, And the shape characteristics of the rings are also different.

Other parallel implementations

Example 7

This example adopts the same implementation method as Example 1, except that the cationic surfactant is octadecyldimethylbenzyl ammonium chloride with better emulsifying properties.

Example 8

Weigh 1g of dioctadecyldimethylammonium bromide and add it to 200mL of deionized water to dissolve, and stir mechanically for 3h to form a uniform template solution;

Add 0.2 g of sodium polyacrylate to the template solution, adjust the pH of the system to 8 with ammonia water, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 40 mL of ethanol to the first micelle solution and stir for 10 min, then add 2 g of tetraethyl orthosilicate, heat up to 40° C. and stir for 12 h to obtain a porous silica nanoring dispersion;

The porous silicon dioxide nano-ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano-ring.

Example 9

Weigh 0.5g of cetyltrimethylammonium bromide and add it to 200mL of distilled water to dissolve, and mechanically stir for 3h to form a uniform template solution;

Add 2 g of sodium stearate to the template solution, adjust the pH to 10 with triethanolamine, stir mechanically for 2 hours, and obtain the first micellar solution with lamellar micelles after fully dissolving;

Add 60 mL of ethylene glycol to the first micelle solution and stir for 10 min, then add 10 g of 3-aminopropyltriethoxysilane, heat up to 65°C and stir for 1 h to obtain a porous silica nanoring dispersion;

The obtained porous silicon dioxide nano ring dispersion is purified and spray-dried to obtain the porous silicon dioxide nano ring.

Example 10

This example adopts the same implementation as Example 3, except that the first shape control agent is sodium dodecylbenzene sulfonate with better emulsifying performance.

Example 11

This example adopts the same implementation method as Example 1, except that the first shape control agent is sodium sulfate.

Example 12

This example adopts the same implementation method as Example 3, except that the first shape control agent is ammonium chloride.

Example 13

This example adopts the same implementation method as Example 1, except that the first shape control agent is vanillic acid.

Example 14

This example adopts the same implementation method as Example 1, except that the first shape control agent is citric acid.

Example 15

This example adopts the same implementation method as Example 1, except that the second shape control agent is butanol.

Example 16

This example adopts the same implementation method as Example 4, except that the second shape control agent is glycerol.

Example 17

This example adopts the same implementation method as Example 6, except that the second shape control agent is ethylene glycol.

Example 18

This example adopts the same implementation method as Example 1, except that the second shape control agent is isopropanol.

Example 19

This example adopts the same implementation method as Example 1, except that the second shape control agent is hydroxymethyl cellulose.

Example 20

This example adopts the same implementation method as Example 1, except that the silicon dioxide precursor is methyltriethoxysilane.

Example 21

This example adopts the same implementation method as Example 1, except that the silicon dioxide precursor is bis-[γ-(triethoxysilyl)propyl]-disulfide.

Example 22

This example adopts the same implementation method as Example 1, except that the silicon dioxide precursor is 1,2-bis(triethoxysilyl)ethane.

Example 23

This example adopts the same implementation method as Example 2, except that the temperature of the heating reaction is 20° C., and the reaction time is 24 hours.

Example 24

This example adopts the same implementation method as Example 3, except that the temperature of the heating reaction is 30° C., and the reaction time is 6 hours.

Example 25

This example adopts the same implementation method as Example 4, except that the temperature of the heating reaction is 50° C., and the reaction time is 6 hours.

Example 26

This example adopts the same implementation method as Example 2, except that the temperature of the heating reaction is 75° C., and the reaction time is 6 hours.

Example 27

This example adopts the same implementation method as Example 6, except that the temperature of the heating reaction is 85° C., and the reaction time is 3 hours.

After testing, all of Examples 7-27 can produce porous silica with a nano-ring structure.

The technical features of the above-mentioned embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-mentioned embodiments are not described. However, as long as there is no contradiction in the combination of these technical features, should be considered as within the scope of this specification.

The above-mentioned embodiments only express several implementation modes of the present invention, and the descriptions thereof are relatively specific and detailed, but should not be construed as limiting the patent scope of the invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (11)

1. a preparation method of porous silicon dioxide nano ring, is characterized in that, comprises the following steps: Prepare a template solution, the template solution is an aqueous solution of cationic surfactant; Provide the first morphology control agent, fully mix it with the template solution, and adjust the pH value of the system to 2-13 to obtain the first micellar solution with lamellar micelles, the first morphology control agent The chemical structure includes at least one functional group capable of interacting with cationic surfactants to form lamellar micellar compounds; Provide a second shape control agent, fully mix it with the first micellar solution to obtain a second micellar solution with ring micelles, the second shape control agent is a hydrophilic compound containing -OH functional group compound; Provide a silicon dioxide precursor, mix it with the second micellar solution, and heat up to react to obtain a porous silicon dioxide nanoring dispersion; The porous silica nanoring dispersion is purified to obtain porous silica nanorings. 2. preparation method as claimed in claim 1, is characterized in that, in described template solution, the addition of cationic surfactant is 0.25-2.5wt%; The cationic surfactant is selected from cationic emulsifiers. 3. preparation method as claimed in claim 2 is characterized in that, described cationic emulsifier is selected from alkyl quaternary ammonium salt, the quaternary ammonium salt containing heteroatom, the quaternary ammonium salt containing benzene ring, amine salt type cationic emulsification one of the agents. 4. The preparation method according to claim 1, wherein the first shape control agent is selected from one of water-soluble salts, water-soluble organic acids, anionic emulsifiers, and anionic polymers, wherein , the water-soluble salt contains ClO ₄ ⁻ , Cl ⁻ , NO ₃ ⁻ , SO ₄ ^2- or SO ₃ ^2- , and the water-soluble organic acid contains carboxylic acid, sulfonic acid, sulfinic acid or thiocarboxylic acid functional group. 5. preparation method as claimed in claim 4, is characterized in that, described anionic emulsifier is selected from the one in carboxylate type, sulfonate type, sulfate type; The anionic polymer is selected from one of sodium polyacrylate, sodium polymethacrylate, sodium polystyrene sulfonate, anionic water-based polyurethane, and anionic polyacrylamide. 6. The preparation method according to claim 1, characterized in that, the pH range of the system is 8-11. 7. The preparation method according to claim 1, wherein the second shape control agent is an alcohol substance, and its consumption is 3-30wt%; The alcohols are selected from at least one of hydroxyl-containing hydrophilic macromolecules and hydroxyl-containing hydrophilic small molecules. 8. The preparation method according to claim 7, characterized in that, said hydroxyl-containing hydrophilic small molecule is selected from at least one of ethanol, ethylene glycol, glycerol, and diethylene glycol. 9. The preparation method according to claim 1, wherein the silica precursor is selected from sodium silicate, methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, silane coupling One or a mixture of two or more of the agents. 10. The preparation method according to claim 1, characterized in that, the specific step of the heating reaction is: stirring and reacting at 20-85°C for 1-36h. 11. A porous silica nanoring, characterized in that it is prepared by the preparation method according to any one of claims 1-10, and the porous silica nanoring has an inner diameter of 20-5000nm and an outer diameter of 500nm - 10 μm porous ring.

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