CN106957056A - A kind of synthetic method of the compound feature onion shape mesoporous material of carbon silicon - Google Patents

Abstract

The present invention relates to a kind of synthetic method of the compound feature onion shape mesoporous material of carbon silicon, by template, mixing and stirring obtains clear solution in proportion with water first, add acid solution, nonionic surfactant Span80, silicon source and carbon source into clear solution successively again, insulation stands to obtain mixed liquor after stirring；Then mixed liquor heating is continued to react, is centrifuged, washs after the completion of reaction, dry solid matter；Solid matter finally is placed in into calcining under protective atmosphere to produce.The mesoporous material that the present invention is prepared has the pore structure of multilayer laminar structure, equally distributed aperture, big specific surface area, big pore volume and the height bending of high-sequential, due to the characteristic (order, dispersiveness, stability) and doping component in its structure in light, electrically and magnetically in terms of feature so that the feature mesoporous material is with a wide range of applications in fields such as Drug controlled release, biology sensor, nano-devices.

Description

Synthesis method of a carbon-silicon composite functional onion-like mesoporous material

technical field

The invention relates to the technical field of functional materials, in particular to a synthesis method of a carbon-silicon composite functional onion-like mesoporous material.

Background technique

Compared with mesoporous materials with conventional morphology, onion-like mesoporous materials, as a new type of mesoporous materials, have unique geometric structures, such as highly ordered multi-layered structure, uniformly distributed pore size, and large specific surface area. , large pore volume and highly curved pore structure, which makes onion-like mesoporous materials have novel physical and chemical properties, such as large closed pores, high surface area, low density, fast diffusion, high thermal and mechanical stability sex. In order to obtain mesoporous materials with higher stability or better catalytic performance, many non-metallic elements are introduced into silicon-based mesoporous materials, such as titanium, carbon, etc., so that the doped onion-like mesoporous materials can make full use of The structural characteristics of onion-like mesoporous materials, on the other hand, can also give full play to the functionalities of doped components in terms of light, electricity, and magnetism, and combine the two to prepare functional onion-like mesoporous materials. It has unique features. These unique features make it a potential application in the fields of controlled drug release, catalysis, biosensors, adsorption, chemical and biological separations, chromatography and nanodevices.

The carbon sources that have been reported so far are very rich, including benzene, furfural, sucrose, furfuryl alcohol, divinylbenzene, phenolic resin, etc. Among them, benzene, furfural, and furfuryl alcohol are highly toxic substances compared with phenolic resin, and phenolic resin has synthetic properties. The advantages of simplicity, cheapness, and availability. In addition, different carbon sources will undergo different carbonization processes, thereby affecting the morphology and microstructure of the mesoporous material. Therefore, the present invention selects phenolic resin as the carbon source after numerous tests.

Contents of the invention

The purpose of the present invention is to provide a green synthesis method of carbon-silicon composite functional onion-like mesoporous material, which successfully introduces carbon into the mesoporous material, and adjusts the pore size of the material through the concentration of nonionic surfactants , the morphology of the mesoporous material is controlled by the amount of carbon source, and a functional onion-like mesoporous material with wide applications in the fields of controlled drug release, biosensors, and nanodevices has been prepared. In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A method for synthesizing a carbon-silicon composite functional onion-like mesoporous material, comprising the following steps: (a) mixing and stirring a template agent and a solvent evenly in proportion to obtain a transparent solution; (b) sequentially adding an acidic solution to the transparent solution , non-ionic surfactant Span80, silicon source and carbon source, after stirring, heat preservation and stand still to obtain a mixed solution; (c) the mixed solution is heated up to continue the reaction, and after the reaction is completed, it is centrifuged, washed, and dried to obtain a solid substance; (d) The solid material is calcined under a protective atmosphere to obtain an onion-like mesoporous material.

According to the above scheme, in step (a), the templating agent and the solvent water are stirred and mixed below 40°C.

According to the above scheme, the mass ratio of the nonionic surfactant Span80, the silicon source and the carbon source in step (b) is about 1-3:20:5-15.

According to the above scheme, the acidic solution is hydrochloric acid solution, the silicon source is tetraethyl orthosilicate, and the carbon source is phenolic.

According to the above scheme, after stirring for 12 hours in step (b), the temperature of the solution was raised to 85° C. and allowed to stand for 24 hours.

According to the above scheme, in step (c), the temperature of the mixed solution was raised to 100° C. for 6 h, and the solid matter obtained by centrifugation was washed with ethanol and water respectively, and dried at 60° C.

According to the above scheme, the pore diameter of the carbon-silicon composite functional onion-like mesoporous material is between 2-50 nm.

The pore expander of the present invention adopts the surfactant molecule Span80, and its hydrophilic and hydrophobic parts respectively interact with the hydrophilic and hydrophobic parts of the amphiphilic template agent P123 after being added to the system. The P123 template is transformed from a rod-like micelle into a multilayered vesicle structure, and then coupled with tetraethyl orthosilicate and phenolic formaldehyde, and then fired at a high temperature under the protection of nitrogen to obtain a functional onion-like mesoporous material.

Compared with the prior art, the beneficial effects of the present invention are: (1) when the present invention synthesizes the functional onion-like mesoporous material, a non-toxic pore-enlarging agent is added, which is environmentally friendly; (2) the non-ionic surface activity is confirmed by experiments. The ratio of the agent Span80, silicon source and carbon source, the prepared functional onion-like mesoporous material has a highly ordered multilayer structure, uniformly distributed pore size, large specific surface area, large pore volume and highly curved Pore structure; (3) In the functional onion-like mesoporous material of the present invention, non-metal elements are introduced into the silicon-based mesoporous material, so that the doped onion-like mesoporous material can make full use of the structure of the onion-like mesoporous material On the other hand, it can also give full play to the functionality of the doped component in terms of light, electricity and magnetism. These unique functions make it useful in drug release control, catalysis, biosensors, adsorption, chemical and biological separation, chromatography Potential applications exist in areas such as methods and nanodevices.

Description of drawings

1-15 respectively correspond to TEM images of the mesoporous materials prepared in Examples 1-15 of the present invention.

Figures 16-17 are comparative experimental diagrams of adsorption of cationic dye rhodamine B (RhB) and anionic dye methyl orange (MO) on materials with and without phenolic formaldehyde, respectively.

detailed description

In order to enable those skilled in the art to fully understand the technical solutions and beneficial effects of the present invention, further description will be given below in conjunction with specific examples.

Example 1

Dissolve 2.0g P123 in 64mL deionized water at a constant temperature of 38°C, stir until completely dissolved, then add 10mL concentrated HCl (mass concentration 36%-38%), stir rapidly for 1h, then add 0.2g Span80, continue stirring 30min until an emulsion is formed. Add 4.1 mL of tetraethyl orthosilicate and 1 g of phenolic formaldehyde dropwise, keep stirring for 12 h, then raise the temperature to 85° C., and let stand for 24 h. The obtained substance was transferred to a polytetrafluoroethylene bottle, heated to 100°C in an oven, and kept for 6 hours. After the reaction, the reaction liquid was taken out and centrifuged, washed with ethanol and water, and then placed in a vacuum oven at 60°C for drying. After drying, put it into a tube furnace, and roast it under the protection of nitrogen, and finally get the mesoporous material.

FIG. 1 is a TEM image of the functional onion-like mesoporous material obtained in Example 1. It can be seen from FIG. 1 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 2

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.3 g, and the amount of phenolic formaldehyde was 1 g.

FIG. 2 is a TEM image of the functional onion-like mesoporous material obtained in Example 2. It can be seen from FIG. 2 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 3

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.4 g, and the amount of phenolic formaldehyde was 1 g.

FIG. 3 is a TEM image of the functional onion-like mesoporous material obtained in Example 3. It can be seen from FIG. 3 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 4

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.5 g, and the amount of phenolic formaldehyde was 1 g.

FIG. 4 is a TEM image of the functional onion-like mesoporous material obtained in Example 4. It can be seen from FIG. 4 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 5

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.6 g, and the amount of phenolic formaldehyde was 1 g.

FIG. 5 is a TEM image of the functional onion-like mesoporous material obtained in Example 5. It can be seen from FIG. 5 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 6

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.2 g, and the amount of phenolic formaldehyde was 2 g.

FIG. 6 is a TEM image of the functional onion-like mesoporous material obtained in Example 6. It can be seen from FIG. 6 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 7

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.3 g, and the amount of phenolic formaldehyde was 2 g.

FIG. 7 is a TEM image of the functional onion-like mesoporous material obtained in Example 7. It can be seen from FIG. 7 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 8

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.4 g, and the amount of phenolic formaldehyde was 2 g.

FIG. 8 is a TEM image of the functional onion-like mesoporous material obtained in Example 8. It can be seen from FIG. 8 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 9

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.5 g, and the amount of phenolic formaldehyde was 2 g.

FIG. 9 is a TEM image of the functional onion-like mesoporous material obtained in Example 9. It can be seen from FIG. 9 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 10

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.6 g, and the amount of phenolic formaldehyde was 2 g.

Fig. 10 is a TEM image of the functional onion-like mesoporous material obtained in Example 10. It can be seen from Fig. 10 that a mesoporous material with a layered structure can be obtained under this condition, but it shows a disordered state.

Example 11

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.2 g, and the amount of phenolic formaldehyde was 3 g.

FIG. 11 is a TEM image of the functional onion-like mesoporous material obtained in Example 11. It can be seen from FIG. 11 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 12

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.3 g, and the amount of phenolic formaldehyde was 3 g.

FIG. 12 is a TEM image of the functional onion-like mesoporous material obtained in Example 12. It can be seen from FIG. 12 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 13

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.4 g, and the amount of phenolic formaldehyde was 3 g.

FIG. 13 is a TEM image of the functional onion-like mesoporous material obtained in Example 13. It can be seen from FIG. 13 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 14

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.5 g, and the amount of phenolic formaldehyde was 3 g.

FIG. 14 is a TEM image of the functional onion-like mesoporous material obtained in Example 14. It can be seen from FIG. 14 that a mesoporous material with an ordered layered structure can be obtained under this condition.

Example 15

The mesoporous material was synthesized according to the preparation method of Example 1, except that the amount of Span80 was 0.6 g, and the amount of phenolic formaldehyde was 3 g.

Fig. 15 is a TEM image of the functional onion-like mesoporous material obtained in Example 15. It can be seen from Fig. 15 that no mesoporous material with an ordered layered structure can be obtained under this condition.

Example 16

Preparation concentration is the rhodamine B solution of 40mg/L, gets 50mL in conical flask, adds respectively a certain amount of phenolic-containing mesoporous material (prepared in Example 13) and phenolic-free mesoporous material (except that no phenolic aldehyde, roasting Except that there is no nitrogen protection, other synthesis steps are the same as in Example 13), and pH=4 is adjusted with NaOH and HCl buffer. Shake the adsorption at room temperature to adsorption equilibrium, centrifuge to get the supernatant, then measure the absorbance with a UV-visible spectrophotometer, and calculate the adsorption amount and removal rate.

Fig. 16 is the contrastive experimental diagram of the different kinds of materials obtained in Example 16. As can be seen from Fig. 16, under the same optimal experimental conditions, the composite mesoporous material containing phenolic formaldehyde has a removal rate of more than 99% for rhodamine B dye, However, the removal rate of rhodamine B dye by the mesoporous silicon material without phenolic formaldehyde is lower than 80%.

Example 17

Preparation concentration is the methyl orange solution of 40mg/L, gets 50mL in Erlenmeyer flask, adds respectively a certain amount of mesoporous material containing phenolic formaldehyde and not containing phenolic formaldehyde (two kinds of mesoporous materials are the same as embodiment 16), with NaOH and HCl buffer adjusted to pH=2. Shake the adsorption at room temperature to adsorption equilibrium, centrifuge to get the supernatant, then measure the absorbance with a UV-visible spectrophotometer, and calculate the adsorption amount and removal rate.

Fig. 17 is the contrastive experimental diagram of the different kinds of materials obtained in Example 17. As can be seen from Fig. 17, under the same optimal experimental conditions, the composite mesoporous material containing phenolic formaldehyde has a methyl orange dye removal rate as high as more than 99%. However, the removal rate of methyl orange dye by the mesoporous silicon material without phenolic formaldehyde is lower than 40%.

The onion-like mesoporous materials without phenolic formaldehyde have poor adsorption to anionic dyes. This is because the compound onion-like mesoporous materials containing phenolic formaldehyde have more carbon elements than the onion-like mesoporous silicon materials. Carbon materials have good adsorption properties, so they have good adsorption properties for cationic dyes and anionic dyes.

Embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementations, and the above-mentioned specific implementations are only illustrative, rather than restrictive, and those of ordinary skill in the art will Under the enlightenment of the present invention, without departing from the gist of the present invention and the scope of protection claimed by the claims, many forms of changes can also be made, and these all fall within the scope of protection of the present invention.

Claims (7)

1. a synthetic method of carbon-silicon composite type functional onion-like mesoporous material, is characterized in that, comprises the following steps: (a) template agent, solvent are mixed in proportion and stirred evenly, obtain transparent solution; (b) successively to Add acidic solution, non-ionic surfactant Span80, silicon source and carbon source into the transparent solution, stir and keep warm to obtain the mixed solution; (c) heat the mixed solution to continue the reaction, after the reaction is completed, centrifuge, wash and dry to obtain solid substance; (d) the solid substance is calcined under a protective atmosphere to obtain an onion-like mesoporous material. 2. The synthesis method of a carbon-silicon composite functional onion-like mesoporous material according to claim 1, characterized in that: in step (a), the template agent and solvent water are stirred and mixed below 40°C. 3. the synthetic method of a kind of carbon-silicon composite functional onion-like mesoporous material according to claim 1, is characterized in that: the mass ratio of nonionic surfactant Span80, silicon source and carbon source in step (b) For 1-3:20:5-15. 4. the synthetic method of a kind of carbon-silicon composite functional onion-like mesoporous material according to claim 1, is characterized in that: described acidic solution is hydrochloric acid solution, and described silicon source is tetraethyl orthosilicate, The carbon source is phenolic. 5. The synthesis method of a carbon-silicon composite functional onion-like mesoporous material according to claim 1, characterized in that: in step (b), after stirring for 12 hours, the solution is heated to 85° C. and left to stand for 24 hours. 6. The synthesis method of a carbon-silicon composite functional onion-like mesoporous material according to claim 1, characterized in that: in step (c), the mixed solution is heated to 100°C for 6 hours, and the solid matter obtained by centrifugation is respectively Wash with ethanol and water, and dry at 60°C. 7. The synthesis method of a carbon-silicon composite functional onion-like mesoporous material according to claim 1, wherein the pore diameter of the carbon-silicon composite functional onion-like mesoporous material is between 2-50 nm between.