Preparation method of nano-silica spheres

Abstract

The invention discloses a preparation method of nano-silica spheres. The preparation method of the nano-silica spheres comprises the following steps: (1) preparing a nano-silica sphere suspension: mixing ammonium hydroxide, tetraethyl orthosilicate and an alcoholic solution with a high-shear mixer at the revolving speed of 10,000 to 22,000r / min to obtain the nano-silica sphere suspension; (2) separating the nano-silica spheres: centrifuging and washing the nano-silica sphere suspension, and drying a precipitate to obtain the nano-silica spheres. The preparation method of the nano-silica spheres disclosed by the invention has relative short preparation time, and nano-SiO2 spheres prepared by hydrolysis can be obtained by stirring for 10 to 20 minutes. Moreover, a template agent is not required, the preparation process is simplified, the template agent does not need to be removed by high-temperature calcining, and the cost is lowered; moreover, the particle sizes of the nano-SiO2 spherescan be controlled by controlling the different conditions of revolving speed, temperature and the like in order to meet the requirement on the particle sizes of the nano-SiO2 spheres. The preparationmethod can be applied to the fields of catalysis, stabilizing agents, enhancers, additives, biology and the like.

Description

technical field

[0001] The invention belongs to the field of nanometer materials, and in particular relates to a preparation method of nanometer silicon dioxide spheres. Background technique

[0002] Silicon dioxide (SiO 2 ) has good mechanical strength, thermal stability and chemical inertness, and has always played an extremely important role in the fields of scientific research and industrial technology. Currently, SiO 2 The preparation of the ball mainly adopts the hydrolysis method of ethyl orthosilicate, in order to control the SiO 2 The spherical particle size is added with a template agent, prepared by ordinary hydrolysis or high-temperature hydrothermal method, and then removed by high-temperature calcination, and then uniformly dispersed nano-SiO 2 Balls, this method is time-consuming (generally the stirring process takes about 2h), and the cost is slightly higher.

[0003] In view of this, the present invention proposes a nano-SiO with low cost and short prepa...

Examples

Embodiment 1

[0038] The specific operation steps are as follows:

[0039] (1) Preparation of precursor solution: Mix ethanol and water at a mass ratio of 7:3 to obtain an ethanol solution with a mass fraction of 70%; then add 500 μL tetraethyl orthosilicate (TEOS) to 80 mL of ethanol solution, mix Evenly, the precursor solution was obtained.

[0040] (2) Preparation of nano-silica sphere suspension: put 80mL of the precursor solution in a high-shear mixer for stirring, add 5mL of ammonia water, and stir in a water bath at 30°C at a speed of 10000r / min. After stirring for 5min, you can see Until the appearance of nano-silica, after stirring for 15 minutes, the reaction is completed, and a suspension of nano-silica spheres is obtained. The nano-silica sphere suspension contains nano-silica spheres.

[0041] (3) Separation of nano-silica spheres: Centrifuge and wash the nano-silica sphere suspension with ethanol solution once at a speed of 6000r / min, then place the precipitate in a blast dr...

Embodiment 2

[0044] The specific operation steps of embodiment 2 are the same as embodiment 1, except that, in the step (2) of embodiment 2, the rotating speed of the high shear mixer is 13000r / min.

[0045] figure 2 Nano-SiO prepared for Example 1 of the present invention 2 The TEM image of the ball shows that the sample is spherical and normally distributed.

Embodiment 3

[0047] The specific operation steps of embodiment 3 are the same as embodiment 1, the difference is that in the step (2) of embodiment 3, the rotating speed of the high shear mixer is 16000r / min.

[0048] image 3 Nano-SiO prepared for Example 1 of the present invention 2 The TEM image of the ball shows that the sample is spherical and normally distributed.

technical field

[0001] The invention belongs to the field of nanometer materials, and in particular relates to a preparation method of nanometer silicon dioxide spheres. Background technique

[0002] Silicon dioxide (SiO 2 ) has good mechanical strength, thermal stability and chemical inertness, and has always played an extremely important role in the fields of scientific research and industrial technology. Currently, SiO 2 The preparation of the ball mainly adopts the hydrolysis method of ethyl orthosilicate, in order to control the SiO 2 The spherical particle size is added with a template agent, prepared by ordinary hydrolysis or high-temperature hydrothermal method, and then removed by high-temperature calcination, and then uniformly dispersed nano-SiO 2 Balls, this method is time-consuming (generally the stirring process takes about 2h), and the cost is slightly higher.

[0003] In view of this, the present invention proposes a nano-SiO with low cost and short prepa...

Examples

Embodiment 1

[0038] The specific operation steps are as follows:

[0039] (1) Preparation of precursor solution: Mix ethanol and water at a mass ratio of 7:3 to obtain an ethanol solution with a mass fraction of 70%; then add 500 μL tetraethyl orthosilicate (TEOS) to 80 mL of ethanol solution, mix Evenly, the precursor solution was obtained.

[0040] (2) Preparation of nano-silica sphere suspension: put 80mL of the precursor solution in a high-shear mixer for stirring, add 5mL of ammonia water, and stir in a water bath at 30°C at a speed of 10000r / min. After stirring for 5min, you can see Until the appearance of nano-silica, after stirring for 15 minutes, the reaction is completed, and a suspension of nano-silica spheres is obtained. The nano-silica sphere suspension contains nano-silica spheres.

[0041] (3) Separation of nano-silica spheres: Centrifuge and wash the nano-silica sphere suspension with ethanol solution once at a speed of 6000r / min, then place the precipitate in a blast dr...

Embodiment 2

[0044] The specific operation steps of embodiment 2 are the same as embodiment 1, except that, in the step (2) of embodiment 2, the rotating speed of the high shear mixer is 13000r / min.

[0045] figure 2 Nano-SiO prepared for Example 1 of the present invention 2 The TEM image of the ball shows that the sample is spherical and normally distributed.

Embodiment 3

[0047] The specific operation steps of embodiment 3 are the same as embodiment 1, the difference is that in the step (2) of embodiment 3, the rotating speed of the high shear mixer is 16000r / min.

[0048] image 3 Nano-SiO prepared for Example 1 of the present invention 2 The TEM image of the ball shows that the sample is spherical and normally distributed.

Images