Preparation method of mesoporous silicon-dioxide-coated single-wall carbon nanotubes

Abstract

The invention discloses a preparation method of mesoporous silicon-dioxide-coated single-wall carbon nanotubes. The surfactant molecules are fixed to the surfaces of the single-wall carbon nanotubes by a one-step process, and the coating growth of the mesoporous silicon dioxide shell is induced in a non-covalent bond mode, thereby implementing control on the thickness of the mesoporous silicon dioxide shell and eliminating the occurrence of the self-nucleation phenomenon of silicon oxide. The method can be used for modifying different functional groups on the external surfaces of the mesoporous pore wall and shell, so that the composite material can be easily dispersed in various solvents, thereby enhancing the dispersion stability of the single-wall carbon nanotubes; and meanwhile, the mesoporous pores can be used for loading and transmitting different guest molecules, and thus, the method has wide application prospects.

Description

technical field

[0001] The invention relates to the field of preparation of composite nanomaterials, in particular to a preparation method of mesoporous silicon dioxide-coated single-wall carbon nanotubes. Background technique

[0002] Since the discovery of carbon nanotubes by Dr. Iijima of Japan in 1991 (Nature, volume 354, page 56, 1991), this nanomaterial with a typical one-dimensional hollow tubular structure has been widely used due to its mechanical, optical, electrical and thermal properties. The excellent performance exhibited has attracted extensive attention of scientists. Among them, single-walled carbon nanotubes can be regarded as curled from a single layer of graphene sheets, with a length of several hundred nanometers to several micrometers, and an inner diameter of less than two nanometers, with a larger specific surface area and aspect ratio. The performance is also more prominent, so more research has been done in the fields of composite materials, electr...

Examples

Embodiment 1

[0031] 10 mg of single-walled carbon nanotubes, 10 mg of cetyltrimethylammonium bromide, and 50 mL of deionized water were added to a three-necked flask, and ultrasonically dispersed for 5 minutes to obtain a stable single-walled carbon nanotube dispersion.

[0032] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 8.0, add 0.15mL tetraethyl orthosilicate, and react at 25°C for 4 hours, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0033] After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. Calcinate the precipitate in a muffle furnace at 300°C for 3 hours to remove the template to obtain mesoporous silica-coated single-walled carbon nanotubes

Embodiment 2

[0035] Add 10 mg of single-walled carbon nanotubes, 1000 mg of cetyltrimethylammonium bromide, and 200 mL of deionized water into a three-necked flask, and ultrasonically disperse for 720 minutes to obtain a stable single-walled carbon nanotube dispersion.

[0036] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 12.0, add 0.15mL tetraethyl orthosilicate, and react at 75°C for 8 hours, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0037]After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. The precipitate was calcined in a muffle furnace at 300° C. for 3 hours to remove the template, and then the mesoporous silica-coated single-walled carbon nanotubes were obtained.

Embodiment 3

[0039] Add 10 mg of single-walled carbon nanotubes, 500 mg of cetyltrimethylammonium bromide, and 100 mL of deionized water into a three-necked flask, and ultrasonically disperse for 4 hours to obtain a stable single-walled carbon nanotube dispersion.

[0040] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 11.3, add 0.15mL tetraethyl orthosilicate, and react at 60°C for 12h, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0041] After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. The precipitate was calcined in a muffle furnace at 300 °C for 3 h to remove the template.

[0042] Such as figure 1 As shown by the middle curve 1, the diameter distribution of the mesoporous silica-coated single-walled carbon nanotubes obtained in this embodiment is between 7nm and 13nm.

technical field

[0001] The invention relates to the field of preparation of composite nanomaterials, in particular to a preparation method of mesoporous silicon dioxide-coated single-wall carbon nanotubes. Background technique

[0002] Since the discovery of carbon nanotubes by Dr. Iijima of Japan in 1991 (Nature, volume 354, page 56, 1991), this nanomaterial with a typical one-dimensional hollow tubular structure has been widely used due to its mechanical, optical, electrical and thermal properties. The excellent performance exhibited has attracted extensive attention of scientists. Among them, single-walled carbon nanotubes can be regarded as curled from a single layer of graphene sheets, with a length of several hundred nanometers to several micrometers, and an inner diameter of less than two nanometers, with a larger specific surface area and aspect ratio. The performance is also more prominent, so more research has been done in the fields of composite materials, electr...

Examples

Embodiment 1

[0031] 10 mg of single-walled carbon nanotubes, 10 mg of cetyltrimethylammonium bromide, and 50 mL of deionized water were added to a three-necked flask, and ultrasonically dispersed for 5 minutes to obtain a stable single-walled carbon nanotube dispersion.

[0032] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 8.0, add 0.15mL tetraethyl orthosilicate, and react at 25°C for 4 hours, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0033] After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. Calcinate the precipitate in a muffle furnace at 300°C for 3 hours to remove the template to obtain mesoporous silica-coated single-walled carbon nanotubes

Embodiment 2

[0035] Add 10 mg of single-walled carbon nanotubes, 1000 mg of cetyltrimethylammonium bromide, and 200 mL of deionized water into a three-necked flask, and ultrasonically disperse for 720 minutes to obtain a stable single-walled carbon nanotube dispersion.

[0036] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 12.0, add 0.15mL tetraethyl orthosilicate, and react at 75°C for 8 hours, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0037]After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. The precipitate was calcined in a muffle furnace at 300° C. for 3 hours to remove the template, and then the mesoporous silica-coated single-walled carbon nanotubes were obtained.

Embodiment 3

[0039] Add 10 mg of single-walled carbon nanotubes, 500 mg of cetyltrimethylammonium bromide, and 100 mL of deionized water into a three-necked flask, and ultrasonically disperse for 4 hours to obtain a stable single-walled carbon nanotube dispersion.

[0040] Use 2M sodium hydroxide solution to adjust the pH value of the above dispersion to 11.3, add 0.15mL tetraethyl orthosilicate, and react at 60°C for 12h, so that the mesoporous silica layer is evenly coated on the single-walled carbon the surface of the nanotube.

[0041] After the reaction was finished, a black precipitate was obtained by centrifugation at 11000 rpm. The precipitate was calcined in a muffle furnace at 300 °C for 3 h to remove the template.

[0042] Such as figure 1 As shown by the middle curve 1, the diameter distribution of the mesoporous silica-coated single-walled carbon nanotubes obtained in this embodiment is between 7nm and 13nm.

Images