Method for regulating and controlling morphology of mesoporous material

Abstract

The invention relates to a method for regulating and controlling the morphology of a mesoporous material, in particular to a novel method for regulating and controlling the morphology of a mesoporous SBA-15 material, which comprises the following steps of: regulating reaction conditions including adding a silicon source, acidity, temperature, stirring speed and metal ions or a co-surfactant through an organic / inorganic self-assembly process; mesoporous silica SBA-15 materials with different morphologies are synthesized and comprise structures such as cross-shaped particles, hollow particles, necklace-shaped particles, short rods and the like. The obtained SBA-15 material has important application value in the fields of catalysis, drug sustained release, mesoporous carbon synthesis and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for regulating the morphology of mesoporous materials, in particular, a method for regulating the morphology of mesoporous material SBA-15. BACKGROUND

[0002] Mesoporous silica material is a kind of novel nano-structured material, which has a wide application prospect in the fields of catalysis, separation, nanotechnology, sensor, etc. and has become an important research direction in the field of material research. Due to the unique structure and performance of ordered mesoporous materials and their great value in potential applications, scientists from multiple disciplines have carried out in-depth research and achieved fruitful results.

[0003] The common structure of ordered mesoporous materials includes one-dimensional layered structure (P2), two-dimensional hexagonal structure (P6mm), three-dimensional body-centered cubic structure (Ia3d), three-dimensional body-centered cubic structure (Im3m), three-dimensional simple cubic structure (Pm3n), three-dimensional hexagonal structure (P63 / mmc) and three-dimensional face-centered cubic structure (Fm3m), etc. These unique structures make mesoporous materials have potential application value in many fields. However, the effective application of mesoporous materials not only depends on its internal pore structure, but also is closely related to its macroscopic morphology and microscopic morphology. Therefore, the morphology control of mesoporous materials has become one of the important research hotspots in this field. Compared with MCM-41 material, mesoporous SBA-15 has many advantages as a carrier for enzymes and proteins, such as large specific surface area, multi-level pore structure, adjustable pore size, etc. due to its high specific surface area, excellent thermal stability and ordered hexagonal pore structure. Early reports showed that silica materials with double mesoporous structure showed good immobilization capacity in the process of biological immobilization However, although SBA-15 material has a wide application prospect in many fields, how to accurately control its morphology is still a difficult problem in current research. The present application proposes a new method for systematically controlling the morphology of SBA-15 material by adjusting the synthesis conditions, thereby overcoming the challenge of morphology control and providing a new solution for the optimization of SBA-15 material in more practical applications. SUMMARY

[0004] The purpose of the present application is to provide a method for regulating the morphology of mesoporous materials, in particular, a method for regulating the morphology of mesoporous material SBA-15. By accurately controlling multiple key parameters in the synthesis process, SBA-15 materials with different morphologies can be synthesized in the same system. In the P123 / HCl / H2O / TMOS system, by controlling the synthesis conditions, hexagonal flake-shaped SBA-15 mesoporous material is obtained, and when different concentrations of tin ions are added, it is found that the morphology changes greatly, and when Sn 2+SBA-15 cross-pieces with good dispersity were obtained when the molar ratio of / Si was between 1:50 and 3:50, which indicated that Sn 2+ could effectively increase the aspect ratio of SBA-15 pieces and had certain inhibitory effect on the aggregation of particles. In the reaction system (P123 / HCl / Sn 2+ / H2O / TMOS) of cross-pieces SBA-15, CTAB was added, and hollow piece structure was successfully prepared. Among them, P123, CTAB and stannous chloride can form unstable white complexes, which play a similar role to hard template in the later process and are important for hollowing. In addition, the acidity of the TEOS / P123 / HCl / H2O reaction system is reduced, and the morphology of the products obtained under different stirring speeds is investigated. The results show that under the condition of stirring speed of 500-800, necklace-like SBA-15 is first synthesized. In a similar reaction system, we obtained SBA-15 fibers and short rods, and by adding n-hexanol or ethyl acetate in the system for preparing short rods, we obtained ring-shaped SBA-15, that is, the rod-shaped bending forms a ring structure with the head almost connected to the tail.

[0005] Compared with the prior art, the present application can effectively control the morphology of SBA-15 material, synthesize SBA-15 materials with various morphologies such as short rods, necklaces, hollow pieces, rings and fibers, and provide a new solution for the application of SBA-15 materials in the fields of catalysis, drug release, sensors, nanomaterial templates and the like.

[0006] The method for regulating the morphology of mesoporous material SBA-15 provided by the present application comprises the following steps: 1) Dissolve the triblock copolymer P123 in a mixed solution of deionized water and HCl, then add an auxiliary metal salt and a co-surfactant, and fully stir for 1 hour, then add a silicon source after clarification; 2) After stirring the mixed solution for 10-30 seconds, place it in a water bath at 20-50 DEG C for 20-24 hours; 3) Transfer the reaction solution to an oven, and then stand for a period of time; the oven temperature is 70-100 DEG C, and the time is 12-24 hours; 4) Separate the product, perform suction filtration, wash and dry, then calcine the template agent in a muffle furnace, the calcination temperature is 500-600 DEG C, and the time is 5-8 hours, and finally obtain the SBA-15 material.

[0007] The metal salt in the present application is Co 2+ , Mn 2+ , Sn 2+ , Cu 2+Metal ion nitrate, sulfate, chloride; the co-surfactant is CTAB or n-hexanol; the HCl concentration is 1.5-2.5M; optionally, the metal salt is Sn 2+ , Cu 2+ Metal ion nitrate or chloride.

[0008] The silicon source is tetraethyl orthosilicate (TEOS) or tetramethyl orthosilicate (TMOS); the water bath temperature is 20-50℃, and the time is 12-24h; the oven temperature is 70-100℃, and the time is 12-24h; the calcination temperature is 500-600℃, and the time is 5-8h.

[0009] The method for regulating the morphology of mesoporous material SBA-15 provided by the application is through the following steps: 1) Dissolve the triblock copolymer P123 in a mixed solution of deionized water and HCl, then add the auxiliary SnCl2·2H2O, fully stir for 1 hour, and then add TMOS or TEOS after clarification.

[0010] 2) After stirring the mixed solution for 15 seconds, place it in a 38℃ water bath for 24h.

[0011] 3) Then transfer the reaction solution to an 80℃ oven, and then stand for 24h.

[0012] 4) After the product is filtered, washed, and dried, calcine it in a 550℃ muffle furnace for 5h to remove the template agent, and obtain the SBA-15 white solid powder product.

[0013] In step 1), the triblock copolymer P123 is dissolved in a mixed solution of deionized water and HCl, and CTAB or n-hexanol is added; the final molar ratio of the reactants is: P123: CTAB or n-hexanol: HCl: H2O: SnCl2·2H2O: TMOS = 0.017-0.045: 0-1: 1.42-14.72: 194-483: 0-0.148: 1.

[0014] The method for regulating the morphology of mesoporous material SBA-15 provided by the application is through the following steps: 1) The present invention proposes a method for precisely controlling the morphology of silica SBA-15 materials, which can synthesize SBA-15 materials with various morphologies such as short rods, necklaces, hollow sheets, rings, and fibers. This morphological diversity can provide more options for applications in different fields and meet the needs of specific functionalization.

[0015] 2) By adjusting the reaction conditions (such as temperature, acidity, stirring speed, reaction time, etc.), the morphology of the material can be effectively controlled, and it does not depend on complex operation steps or expensive equipment. This method simplifies the synthesis process while improving production efficiency.

[0016] 3) All synthesized SBA-15 materials have high specific surface area and good pore ordering, which makes them have excellent performance in applications such as catalysis, drug release, adsorption, and separation. Especially in the field of catalysis, SBA-15 materials with highly ordered structure can provide more reaction sites and improve catalytic efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 Small-angle XRD characterization chart of SBA-15 prepared for Example 1.

[0018] Figure 2 SEM characterization chart of SBA-15 hollow sheet white solid powder prepared for Example 2.

[0019] Figure 3 SEM characterization chart of SBA-15 necklace white solid powder prepared for Example 3.

[0020] Figure 4 SEM characterization chart of SBA-15 fiber white solid powder prepared for Example 4.

[0021] Figure 5 SEM characterization chart of SBA-15 short rod white solid powder prepared for Example 5.

[0022] Figure 6 SEM characterization chart of SBA-15 ring white solid powder prepared for Example 6. DETAILED DESCRIPTION

[0023] The invention will be further described by examples, but these examples are not limited to the application of the invention.

[0024] The experimental methods and tests not specified in the examples are usually carried out according to the conventional conditions and the conditions described in the manual, or according to the conditions recommended by the manufacturer; the general equipment, materials, reagents, etc. used, if not specified, can be obtained from commercial channels. EXAMPLE

[0025] A preparation method for regulating the morphology of mesoporous material SBA-15, comprising the following steps: (1) dissolve EO 20 PO 70 EO 20 (P123, triblock copolymer) in a mixed solution of deionized water and HCl, then add SnCl2·2H2O, stir for one hour, then add TMOS (tetramethoxysilane), and the final molar ratio of the reactants is P123:HCl:H2O:SnCl2·2H2O:TMOS=0.017:5.91:194:0.059:1; (2) After stirring the mixed solution for 15s, place it in a 38℃ water bath and react for 24h; (3) Then transfer the reaction solution to an 80℃ oven and react for another 24h; (4) After the product is filtered, washed, and dried, calcine it in a 550℃ muffle furnace for 5h to remove the template agent, and obtain SBA-15 cross-shaped sheet white solid powder product. Embodiment

[0026] The embodiment provides a preparation method for regulating the morphology of mesoporous material SBA-15, comprising the following steps: (1) dissolve EO 20 PO 70 EO 20 (P123), CTAB (hexadecyl trimethyl ammonium bromide) in a mixed solution of deionized water and HCl, then add SnCl2·2H2O, continue to stir for one hour, then add TMOS, and the final molar ratio of the reactants is P123:CTAB:HCl:H2O:SnCl2·2H2O:TMOS=0.017:0.057:5.91:194:0.059:1; (2) After stirring the mixed solution for 15s, place it in a 38℃ water bath and react for 24h; (3) Then transfer the reaction solution to an 80℃ oven and react for another 24h; (4) After the product is filtered, washed, and dried, calcine it in a 550℃ muffle furnace for 5h to remove the template agent, and obtain SBA-15 cross-shaped sheet white solid powder product. Embodiment

[0027] The embodiment provides a preparation method for regulating the morphology of mesoporous material SBA-15, comprising the following steps: (1) dissolve EO 20 PO 70 EO 20(P123) is dissolved in a mixed solution of deionized water and HCl, and then TEOS (Tetraethoxysilan) is added. The final molar ratio of the reactants is P123:HCl:H2O:TEOS=0.019:1.42:229:1; (2) stirring at 30°C for 24 h; (3) transferring to an oven at 80°C and standing for 24 h; (4) after the product is filtered, washed and dried, the template agent is removed by calcining at 550°C for 5 h in a muffle furnace to obtain SBA-15 necklace-shaped white solid powder product. Example

[0028] The embodiment provides a preparation method for regulating the morphology of mesoporous material SBA-15, and comprises the following steps: (1) dissolving EO 20 PO 70 EO 20 (P123) is dissolved in a mixed solution of deionized water and HCl, and then TEOS (Tetraethoxysilan) is added. The final molar ratio of the reactants is P123:HCl:H2O:TEOS=0.019:1.42:229:1; (2) stirring the mixed solution for 15 s, and standing for 24 h in a water bath at 38°C; (3) then transferring the reaction solution to an oven at 100°C, and standing for 24 h; (4) after the product is filtered, washed and dried, the template agent is removed by calcining at 550°C for 5 h in a muffle furnace to obtain SBA-15 necklace-shaped white solid powder product. Example

[0029] The embodiment provides a preparation method for regulating the morphology of mesoporous material SBA-15, and comprises the following steps: (1) dissolving EO 20 PO 70 EO 20 (P123) is dissolved in a mixed solution of deionized water and HCl, and then TEOS (Tetraethoxysilan) is added. The final molar ratio of the reactants is P123:HCl:H2O:TEOS=0.019:1.42:229:1; (2) stirring the mixed solution for 15 s, and standing for 24 h in a water bath at 38°C; (3) then transferring the reaction solution to an oven at 100°C, and standing for 24 h; o ​(4) The product is filtered, washed and dried, and then calcined in a 550 o C muffle furnace for 5 hours to remove the template agent, to obtain SBA-15 short rod white solid powder product. Example

[0030] The present example provides a preparation method for regulating the morphology of mesoporous material SBA-15, comprising the following steps: (1) Dissolve EO 20 PO 70 EO 20 (P123) in a mixed solution of deionized water and HCl, and after stirring for one hour, add SnCl2·2H2O and n-hexanol, continue to stir for half an hour, and then add TEOS. The final molar ratio of the reactants is P123:HCl:H2O:SnCl2·2H2O:n-hexanol:TEOS=0.026:8.87:291:0.089:0.088:1; (2) After stirring the mixed solution for 15 seconds, place it in a 38°C water bath and react for 24 hours; (3) Then transfer the reaction solution to an 80 o C oven, and react for another 24 hours; (4) The product is filtered, washed and dried, and then calcined in a 550 o C muffle furnace for 5 hours to remove the template agent, to obtain SBA-15 short rod white solid powder product.

[0031] The specific structural parameters of each shape product are as follows: Figures 2-6 . Example

[0032] The different morphology SBA-15 synthesized above were applied as representative materials for the immobilization of lysozyme and bovine serum albumin. 5 mg of SBA-15 sample was added to 5 mL of 0.5 mg / mL lysozyme solution and shaken on a shaker at 120 rpm for a certain time at room temperature. Then the mixture was centrifuged at 8000 r / min for 5 min and the supernatant was reserved. The supernatant was washed twice with buffer and centrifuged again. The washing and centrifugation were repeated three times. The supernatants were mixed and the absorbance was measured at 280 nm on a UV spectrophotometer. The amount of lysozyme immobilized was calculated from the difference in absorbance of the enzyme solution before and after adsorption according to the Bradford formula based on the calibration curve. The immobilization of bovine serum albumin was similar to that of lysozyme. 5 mg of SBA-15 was added to 5 mL of 1 mg / mL bovine serum albumin solution and shaken on a shaker at 120 rpm for 24 h at room temperature. After centrifugation and washing, the supernatant was mixed with the washing solution and reserved. The absorbance of the initial solution and the supernatant was measured at 280 nm on a UV spectrophotometer. The amount of bovine serum albumin immobilized was calculated according to the Bradford formula. The pore structure of the four materials and the saturated adsorption amount of lysozyme and bovine serum albumin are listed in Table 1. Since the fibrous SBA-15 has a larger pore size, it has a higher adsorption amount of lysozyme. The hollow sheet and necklace have smaller pore sizes, and the corresponding adsorption amount is smaller. In order to further evaluate the adsorption performance of these materials, we selected bovine serum albumin with a larger molecular size. Similarly, fibrous SBA-15 has the highest adsorption amount, which is mainly due to its larger pore size and hierarchical pore structure.

[0033]

[0034] The above only describes specific embodiments of the present application. It should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, which should also be considered within the scope of protection of the present application.

Claims

1. A method for regulating the morphology of mesoporous material SBA-15, characterized in that Steps involved: 1) Dissolve the triblock copolymer P123 in a mixed solution of deionized water and HCl, then add the auxiliary metal salt and co-surfactant, stir thoroughly for 1 hour, and add the silicon source after clarification; 2) Stir the mixed solution for 10-30 seconds, then place it in a 20-50°C water bath and react for 20-24 hours; 3) Transfer the reaction solution to an oven and let it react for a while; the oven temperature is 70-100°C and the reaction time is 12-24 hours; 4) The product is separated, filtered, washed, dried, and then calcined in a muffle furnace to remove the template at a temperature of 500-600° C. for 5-8 hours to obtain the SBA-15 material.

2. The method according to claim 1, characterized in that The metal salt is Sn²⁺ / Cu²⁺ nitrate / chloride; the co-surfactant is CTAB or n-hexanol.

3. The method according to claim 1, characterized in that The HCl concentration is 1.5-2.5M.

4. The method according to claim 1, characterized in that The silicon source is ethyl orthosilicate or methyl orthosilicate.

5. The method according to claim 1, wherein The water bath temperature is 20-50°C, and the time is 12-24 hours; the oven temperature is 70-100°C, and the time is 12-24 hours; the calcination temperature is 500-600°C, and the time is 5-8 hours.

6. A method for regulating the morphology of mesoporous material SBA-15, characterized in that Steps involved: 1) Dissolve the triblock copolymer P123 in a mixed solution of deionized water and HCl, then add the additive SnCl2·2H2O, stir thoroughly for 1 hour, and add ethyl orthosilicate or methyl orthosilicate after clarification; 2) Stir the mixed solution for 15 seconds and then place it in a 38°C water bath for 24 hours; 3) The reaction solution was then transferred to an 80°C oven and allowed to react for 24 hours. 4) The product was filtered, washed, dried, and then calcined in a muffle furnace at 550°C for 5 hours to remove the template, thereby obtaining SBA-15 as a white solid powder.

7. The method according to claim 6, characterized in that Step 1) The triblock copolymer P123 is dissolved in a mixed solution of deionized water and HCl, and CTAB or n-hexanol is added.

8. The method according to claim 6, characterized in that The final molar ratio of the reactants is: P123:CTAB or n-hexanol:HCl: H2O: SnCl2·2H2O:TMOS=0.017-0.045:0-1:1.42-14.72:194-483:0-0.148:

1.

9. The method according to claim 6, characterized in that The final molar ratio of the reactants is selected from: P123: HCl:H2O:SnCl2·2H2O:TMOS=0.017:5.91:194:0.059:1 P123:CTAB:HCl:H2O:SnCl2·2H2O:TMOS=0.017:0.057:5.91:194:0.059:1; P123:HCl:H2O:TEOS=0.019:1.42:229:1; P123:HCl:H2O:SnCl2·2H2O:TEOS=0.043:14.72:483:0.148:1; P123:HCl:H2O:SnCl2ž2H2O:TEOS=0.026:8.87:291:0.089:1; P123:HCl:H2O:SnCl2ž2H2O:n-hexanol:TEOS=0.026:8.87:291:0.089:0.088:1.

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