Method for preparing nitrogen-doped graphene airgel by modifying plant extract

Abstract

The invention discloses a method for preparing nitrogen doped graphene aerogel through the modification of a plant extract. The method comprises the following steps: taking 1 to 10 parts of a graphene oxide solution, 0.5 to 12 parts of a nitrogen source, and 1 to 30 parts of a plant extract in parts by volume, stirring, and performing ultrasonic dispersion, so as to obtain a mixed liquor; shifting the mixed liquor into a high pressure reaction vessel, and ensuring that the mixed liquor is reacted for 12 to 20h at 80 to 200 DEG, so as to obtain hydrogel; percooling the hydrogel for 1 to 12h at 0 to 20 DEG C after the hydrogel is dialysed, and taking out and naturally drying the hydrogel, so as to obtain the nitrogen doped graphene aerogel. The graphene aerogel prepared through the method has high nitrogen doping content, lays a foundation for the preparation of various nitrogen doped graphene-based function materials, and can be used for preparing various microswitches, micro sensors, supercapacitors, lithium batteries, solar batteries, refractory materials, catalytic materials, adsorption materials and oil absorption materials. The preparation method is simple in technology and convenient to operate, and can realize large-scale production.

Description

technical field

[0001] The invention relates to a method for preparing graphene airgel, in particular to a method for preparing nitrogen-doped graphene airgel by modifying plant extracts. Background technique

[0002] The unique electrical, thermal and mechanical properties of graphene make it have broad application prospects in electronic devices, composite materials, sensors, energy storage and other fields. For all known reasons, the conductivity of graphene cannot be fully controlled because it has no band gap. Graphene is doped by replacing carbon atoms with heteroatoms including N, B, P, S, etc. to form point defects to open its band gap and modulate the conductivity type. Therefore, the element doping of graphene has become a research boom and has been reported by a large number of literatures in recent years. Nitrogen doping of graphene is the most common doping method, and various functional graphene materials based on nitrogen doping have been prepared. We know ...

Examples

Embodiment 1

[0038] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0039] Step 1, take 6mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 3mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0040]Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0041] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene airgel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 1%. , The dialysis time is 6h.

[0042] figure 2 (a-f) shows the SEM picture of the nitrogen-doped graphene airgel that embodiment 1 prepares; It c...

Embodiment 2

[0047] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0048] Step 1, take 6mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 1mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0049] Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0050] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene airgel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 1%. , The dialysis time is 6h.

Embodiment 3

[0052] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0053] Step 1, take 4mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 5mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0054] Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0055] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene aerogel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 5% , The dialysis time is 6h.

technical field

[0001] The invention relates to a method for preparing graphene airgel, in particular to a method for preparing nitrogen-doped graphene airgel by modifying plant extracts. Background technique

[0002] The unique electrical, thermal and mechanical properties of graphene make it have broad application prospects in electronic devices, composite materials, sensors, energy storage and other fields. For all known reasons, the conductivity of graphene cannot be fully controlled because it has no band gap. Graphene is doped by replacing carbon atoms with heteroatoms including N, B, P, S, etc. to form point defects to open its band gap and modulate the conductivity type. Therefore, the element doping of graphene has become a research boom and has been reported by a large number of literatures in recent years. Nitrogen doping of graphene is the most common doping method, and various functional graphene materials based on nitrogen doping have been prepared. We know ...

Examples

Embodiment 1

[0038] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0039] Step 1, take 6mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 3mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0040]Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0041] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene airgel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 1%. , The dialysis time is 6h.

[0042] figure 2 (a-f) shows the SEM picture of the nitrogen-doped graphene airgel that embodiment 1 prepares; It c...

Embodiment 2

[0047] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0048] Step 1, take 6mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 1mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0049] Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0050] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene airgel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 1%. , The dialysis time is 6h.

Embodiment 3

[0052] A method utilizing plant extract modification to prepare nitrogen-doped graphene airgel, comprising the following steps:

[0053] Step 1, take 4mL of 10mg / L graphene oxide solution and 4mL of concentrated ammonia water and stir, then add 60mg of urea and 5mL of 0.3g / mL P. chinensis plant extract, stir, and ultrasonically disperse to obtain a mixed material liquid; The power is 800W, and the ultrasonic frequency is 35KHz;

[0054] Step 2. Move the mixed material liquid to a high-pressure reactor with a Teflon lining, and react at a temperature of 180° C. for 12 hours to obtain a hydrogel;

[0055] Step 3, pre-cool the hydrogel at -17°C for 12 hours after dialysis, take it out and dry it naturally to obtain nitrogen-doped graphene aerogel; the dialysate used in the dialysis is ethanol aqueous solution with a concentration of 5% , The dialysis time is 6h.

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