Preparation method of controlled fluorescent graphene quantum dot

Abstract

The invention discloses a preparation method of a controlled fluorescent graphene quantum dot. The preparation method comprises the following steps: uniformly and quickly dispersing graphite oxide into ultrapure water by ultrasonic action to obtain a dispersion liquid of graphite oxide; adding different amount of hydrogen peroxide solution into the obtained dispersion liquid of graphite oxide, and at last, obtaining the graphene quantum dot under ultraviolet radiation. The preparation method disclosed by the invention is simple, and short in technology process; the prepared product is small in particle size, uniform in distribution, and excellent in fluorescent property; the conditions can be controlled to prepare the graphene quantum dot with the required wavelength.

Description

technical field

[0001] The invention belongs to the technical field of nanomaterial preparation, and in particular relates to a preparation method of controllable fluorescent graphene quantum dots. Background technique

[0002] Graphene (GQDs) is a carbon atom with SP 2 The hexagonal carbon material composed of hybrid orbitals is only the thickness of a layer of single atoms. Graphene quantum dots not only have the advantages of strong hardness, high thermal conductivity, fast electron mobility, and low resistivity of graphene, but also have new physical properties due to quantum confinement effects and boundary effects when their size is less than 10nm. . Therefore, graphene quantum dots are widely used in biological cell imaging, biomarkers, electrochemical sensing, nanoelectrodes and so on.

[0003] There are various methods for preparing graphene in the prior art, which can be summarized into two categories: top-down and bottom-up. The top-down method refers to cutti...

Examples

Embodiment 1

[0032] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add 5mL of hydrogen peroxide (30%), add 125mL of ultrapure water, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

[0033] Such as figure 2 as shown, figure 2 A, B, C, D, E, and F in A, B, C, D, E, and F indicate that the radiation time is 5min, 10min, 15min, 20min, 25min, and 30min; when the radiation time is 5min, the particle size of GQDs is still relatively large; when the radiation time is prolonged At 30min, the diameter of GQDs is only 5nm, and the particle size distribution is uniform.

Embodiment 2

[0035] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add hydrogen peroxide (30%) 25mL, add water 105mL, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

Embodiment 3

[0037] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add hydrogen peroxide (30%) 50mL, add water 80mL, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

[0038] Such as image 3 as shown, image 3 Among them, A, B, and C are respectively the fluorescence spectrum diagrams of the graphene quantum dots prepared in Examples 1, 2, and 3; it can be seen that the GQDs obtained under different radiation times generally have blue shifts in their fluorescence maximum wavelengths. When the excitation wavelength When both were at 370nm, the maximum emission wavelength of GQDs moved from 650nm (0min) to 500nm (60min); the fluorescence intensity was the strongest when the irradiation time was 30min, and the maximum emission ...

technical field

[0001] The invention belongs to the technical field of nanomaterial preparation, and in particular relates to a preparation method of controllable fluorescent graphene quantum dots. Background technique

[0002] Graphene (GQDs) is a carbon atom with SP 2 The hexagonal carbon material composed of hybrid orbitals is only the thickness of a layer of single atoms. Graphene quantum dots not only have the advantages of strong hardness, high thermal conductivity, fast electron mobility, and low resistivity of graphene, but also have new physical properties due to quantum confinement effects and boundary effects when their size is less than 10nm. . Therefore, graphene quantum dots are widely used in biological cell imaging, biomarkers, electrochemical sensing, nanoelectrodes and so on.

[0003] There are various methods for preparing graphene in the prior art, which can be summarized into two categories: top-down and bottom-up. The top-down method refers to cutti...

Examples

Embodiment 1

[0032] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add 5mL of hydrogen peroxide (30%), add 125mL of ultrapure water, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

[0033] Such as figure 2 as shown, figure 2 A, B, C, D, E, and F in A, B, C, D, E, and F indicate that the radiation time is 5min, 10min, 15min, 20min, 25min, and 30min; when the radiation time is 5min, the particle size of GQDs is still relatively large; when the radiation time is prolonged At 30min, the diameter of GQDs is only 5nm, and the particle size distribution is uniform.

Embodiment 2

[0035] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add hydrogen peroxide (30%) 25mL, add water 105mL, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

Embodiment 3

[0037] Weigh 0.0150g of graphite oxide and add 20mL of ultrapure water. Sonicate for 30min, then add hydrogen peroxide (30%) 50mL, add water 80mL, and then irradiate under high-pressure mercury vapor arc lamp. A sample is taken before irradiation, and a sample is taken at the irradiation time of 5min, 10min, 15min, 20min, 25min, 30min, 45min, and 60min. This series of solutions is the prepared graphene quantum dots.

[0038] Such as image 3 as shown, image 3 Among them, A, B, and C are respectively the fluorescence spectrum diagrams of the graphene quantum dots prepared in Examples 1, 2, and 3; it can be seen that the GQDs obtained under different radiation times generally have blue shifts in their fluorescence maximum wavelengths. When the excitation wavelength When both were at 370nm, the maximum emission wavelength of GQDs moved from 650nm (0min) to 500nm (60min); the fluorescence intensity was the strongest when the irradiation time was 30min, and the maximum emission ...

Images