阅读说明：本技术 一种单分散多孔二氧化硅球材料的制备方法 (Preparation method of monodisperse porous silicon dioxide sphere material ) 是由 赵东元 朱洪伟 刘玉普 于 2018-04-02 设计创作，主要内容包括：本发明提出了一种单分散多孔二氧化硅球材料的制备方法,包括,(1)将表面活性剂和催化剂溶解到水中,高速搅拌至澄清溶液；将硅源溶于有机溶剂中,得到有机溶液；将有机溶液加入到澄清溶液中,形成油水混相体系；(2)油水混相体系在温度40-80℃中反应；得到单分散纳米球；(3)去除其中的表面活性剂,得到单分散多孔二氧化硅球材料。本发明采用了油-水两相混溶反应体系,由于有机相的扩孔效果,所得无机二氧化硅球的孔径最高可达70nm。同时,可以对无机二氧化硅球的孔径进行调控,实现其孔径在15～70nm之间的自由调控。(The invention provides a preparation method of a monodisperse porous silica sphere material, which comprises the following steps of (1) dissolving a surfactant and a catalyst into water, and stirring at a high speed until a clear solution is obtained; dissolving a silicon source in an organic solvent to obtain an organic solution; adding the organic solution into the clear solution to form an oil-water mixed phase system; (2) reacting the oil-water mixed phase system at the temperature of 40-80 ℃; obtaining monodisperse nanospheres; (3) and removing the surfactant to obtain the monodisperse porous silica ball material. The invention adopts an oil-water two-phase miscible reaction system, and the pore diameter of the obtained inorganic silica spheres can reach 70nm at most due to the hole expansion effect of an organic phase. Meanwhile, the aperture of the inorganic silica spheres can be regulated, and the aperture of the inorganic silica spheres can be freely regulated and controlled between 15 nm and 70 nm.)

1. A preparation method of a monodisperse porous silica sphere material is characterized by comprising the following steps:

(1) dissolving a surfactant and a catalyst into water, and stirring at a high speed to obtain a clear solution; the concentration of the surfactant in the clear solution is 1.0-22 wt%;

dissolving a silicon source in an organic solvent to obtain an organic solution; wherein the concentration of the silicon source is 3-50 wt%;

adding the organic solution into the clarified solution to form an oil-water mixed phase system;

the mass ratio of the surfactant to the silicon source is 0.25-8.0;

(2) the oil-water mixed phase system reacts at the temperature of 40-80 ℃; obtaining monodisperse nanospheres;

(3) and (3) heating the monodisperse nanospheres from room temperature to 400-800 ℃ in the air atmosphere, and keeping the temperature for 1-10h to remove the surfactant in the monodisperse porous silica nanospheres to obtain the monodisperse porous silica sphere material.

2. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the surfactant is one or more selected from quaternary ammonium salt cationic surfactants.

3. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the catalyst is selected from one or more of ammonia water, aliphatic amine, alcohol amine, aromatic amine, and amide.

4. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the surfactant is one or more selected from the group consisting of cetyltrimethylammonium chloride, cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride, and octadecyltrimethylammonium bromide;

the catalyst is selected from one or more of octylamine, dodecylamine, triethanolamine and diethanolamine.

5. The method of claim 1 or 3, wherein the concentration of the catalyst in the clarified solution is 0.01 to 1.0 wt%.

6. The method as claimed in claim 1, wherein the stirring speed of the high-speed stirring is 150-800 rpm, and the time is controlled to be 0.25-5 h.

7. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the silicon source is selected from one or more of sodium silicate, fumed silica, and ethyl orthosilicate.

8. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the organic solvent is one or more selected from dioxane, cyclohexane, n-hexane, decalin, and olefin.

9. The method for preparing a monodisperse porous silica sphere material according to claim 1, wherein the reaction time in step (2) is 2-24 h; the heating rate in the step (3) is 1 ℃/min.

10. The method according to claim 1, wherein the pores of the monodisperse porous silica sphere material are of a central divergent type; the prepared monodisperse porous silicon dioxide ball material is a framework formed by tightly packing silicon dioxide, the diameter of the framework is 60-500 nm, and the specific surface area of the framework is 600-1600 m²A pore diameter of 15 to 70nm and a pore volume of 0.61 to 2.8cm³/g。

Technical Field

The invention relates to the technical field of nano material preparation, in particular to a preparation method of a monodisperse porous silicon dioxide sphere material.

Background

The porous silica spheres have the characteristics of high porosity, large specific surface area, stable chemical property, low cost, good hydrophilicity, no toxicity and the like, so the porous silica spheres are widely applied to the fields of adsorption, catalysis, filtration, biomedicine and the like. Due to the limitations of commercial surfactants, it is often difficult to prepare silica sphere materials with larger pore sizes, and preparing monodisperse porous silica spheres with pore sizes greater than 20nm remains a great technical challenge.

Disclosure of Invention

The invention provides a preparation method of a monodisperse porous silica sphere material, which solves the problems of small aperture and small aperture adjustable range of the porous silica sphere material in the prior art.

The technical scheme of the invention is realized as follows:

a preparation method of a monodisperse porous silica sphere material comprises the following steps:

(1) dissolving a surfactant and a proper amount of catalyst into water, and stirring at a high speed to obtain a clear solution; the concentration of the surfactant in the clear solution is 1.0-22 wt%;

dissolving a silicon source in an organic solvent to obtain an organic solution; wherein the concentration of the silicon source is 3-50 wt%;

adding the organic solution into the clarified solution to form an oil-water mixed phase system;

the mass ratio of the surfactant to the silicon source is 0.25-8.0;

(2) the oil-water mixed phase system reacts at the temperature of 40-80 ℃; obtaining monodisperse nanospheres;

(3) and (3) heating the monodisperse pore size spheres from room temperature to 400-800 ℃ in an air atmosphere, and keeping the temperature for 1-10h to remove the surfactant in the monodisperse pore size spheres to obtain the monodisperse porous silica sphere material.

As a preferable technical scheme, the surfactant is selected from one or more of quaternary ammonium salt cationic surfactants; the quaternary ammonium salt cationic surfactant; including but not limited to cetyltrimethylammonium chloride, cetyltrimethylammonium bromide, octadecyltrimethylammonium chloride, and octadecyltrimethylammonium bromide, and the like.

As the preferred technical scheme, the catalyst is selected from one or more of ammonia water, aliphatic amine, alcohol amine, aromatic amine and amide; including but not limited to octylamine, dodecylamine, triethanolamine, diethanolamine.

As a preferred embodiment, the concentration of the catalyst in the clear solution is 0.01 to 1.0 wt%.

As a preferable technical proposal, the stirring speed of the high-speed stirring is 150-800 r/min, and the time is controlled to be 0.25-5 h.

As a preferred technical scheme, the silicon source is selected from one or more of sodium silicate, fumed silica and tetraethoxysilane.

As a preferable technical scheme, the organic solvent is selected from one or more of dioxane, cyclohexane, normal hexane, decalin and olefin.

As a preferable technical scheme, the reaction time in the step (2) is 2-24 h; the heating rate in the step (3) is 1 ℃/min.

As a preferable technical scheme, the pore channels of the monodisperse porous silica ball material are in a center divergent type.

The monodisperse porous silica ball material prepared by the method is a framework formed by closely packing silica. By modulating the parameters of the organic phase, the diameter of which is of the order of magnitude60 to 500nm, and a specific surface area of 600 to 1600m²A pore diameter of 15 to 70nm and a pore volume of 0.61 to 2.8cm³/g。

Advantageous effects

(1) The invention adopts an oil-water two-phase miscible reaction system, and the pore diameter of the obtained inorganic silicon dioxide spheres is much higher than that of the inorganic silicon dioxide spheres (less than or equal to 18nm) due to the hole expanding effect of an organic phase, and can reach 70nm at most. Meanwhile, the aperture of the inorganic silicon dioxide spheres can be regulated and controlled by regulating the parameters of the organic phase (such as the change of an organic solvent or the concentration of a silicon source), so that the aperture can be freely regulated and controlled between 15 nm and 70 nm.

(2) In the preparation method, the mixing and dissolving reaction system simply blends the organic phase system and the water phase system without considering the maintenance of the layered interface of the two-phase system, so the method has simple operation and high repetition rate and can be suitable for large-scale industrial production.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without inventive exercise.

Fig. 1 is a Scanning Electron Microscope (SEM) image of the monodisperse porous silica spheres of example 1.

FIG. 2 is a second scanning electron microscope (TEM) image of the monodisperse porous silica sphere material of example 1.

FIG. 3 is a characteristic Transmission Electron Microscope (TEM) image of a monodisperse porous silica sphere material of example 1.

Fig. 4 is a characteristic nitrogen adsorption-desorption isotherm of the monodisperse porous silica sphere material of example 1.

FIG. 5 is a characteristic pore size distribution curve of the monodisperse porous silica sphere material of example 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The substances mentioned in the following examples are all commercially available.