阅读说明：本技术 一种氟含量可控的氟化石墨烯和氟化碳纳米管的制备方法 (Preparation method of fluorinated graphene and fluorinated carbon nanotube with controllable fluorine content ) 是由 郭兆琦 杨娜 耶金 程彦飞 王煜 马海霞 于 2020-12-15 设计创作，主要内容包括：本发明提供一种氟含量可控的氟化石墨烯和氟化碳纳米管的制备方法将石墨烯与1,4-二碘全氟丁烷或将碳纳米管与1,4-二碘全氟丁烷加入到安瓿瓶中,混合均匀,然后在液氮冷冻下,抽真空,最后煅烧,得到氟化石墨烯或氟化碳纳米管。本发明通过气固相反应合成氟化石墨烯和氟化碳纳米管,对设备要求低,原料毒性小且工艺过程简单,可操作性较强,产物的氟含量可控。(The invention provides a preparation method of fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content, which comprises the steps of adding graphene and 1, 4-diiodoperfluorobutane or adding carbon nanotubes and 1, 4-diiodoperfluorobutane into an ampoule bottle, uniformly mixing, then vacuumizing under the freezing of liquid nitrogen, and finally calcining to obtain the fluorinated graphene or the fluorinated carbon nanotubes. The method synthesizes the fluorinated graphene and the fluorinated carbon nanotube through a gas-solid reaction, has low requirement on equipment, small toxicity of raw materials, simple process, strong operability and controllable fluorine content of the product.)

1. A preparation method of fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content is characterized by comprising the following steps: adding graphene and 1, 4-diiodoperfluorobutane or adding a carbon nano tube and the 1, 4-diiodoperfluorobutane into an ampoule bottle, uniformly mixing, then freezing in liquid nitrogen, vacuumizing, and finally calcining to obtain the fluorinated graphene or the fluorinated carbon nano tube.

2. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: the content of fluorine atoms in the fluorinated graphene is 0.01-50%.

3. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: the content of fluorine atoms in the fluorinated carbon nano tube is 0.01-50%.

4. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: the calcination temperature is 200-500 ℃, and the calcination time is 0.1-48 hours.

5. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: the calcination temperature was 360 ℃ and the calcination time was 1 hour.

6. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 5, wherein the method comprises the following steps: the temperature is raised from room temperature to 200-500 ℃ at a temperature rise rate of 5 ℃/min.

7. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: and after calcination, dispersing the calcined product in an organic solvent, washing and drying to obtain the fluorinated graphene or the fluorinated carbon nanotube.

8. The method for preparing fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content according to claim 1, wherein the method comprises the following steps: the organic solvent is ethanol, methanol, acetone, dichloromethane, chloroform, carbon tetrachloride, tetrahydrofuran, acetonitrile or ethyl acetate.

Technical Field

The invention belongs to the technical field of carbon fluoride materials, and relates to a preparation method of fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content.

Background

Graphene and carbon nanotubes are another milestone of significant scientific discovery in the field of nanomaterial research following fullerenes. Stone (stone)The ink-based basic structural unit is a benzene six-membered ring structure which is most stable in organic materials, and carbon atoms are all in sp form²Hybridized and connected to form the two-dimensional atomic crystal with a monoatomic layer structure. The carbon nano tube is a one-dimensional material which is formed by curling graphite and has a seamless, hollow single-wall or multi-wall tubular structure, and has excellent mechanical property and electric conductivity, good lithium intercalation property and extremely high length-diameter ratio. Fluorine with extremely strong electronegativity reacts with the carbon material, and the obtained carbon fluoride material can obviously improve the properties of the carbon material, such as surface polarity, electric conductivity, adsorption capacity and the like. The carbon fluoride material is used as the active material of the positive electrode material of a primary battery-lithium battery, so that the battery duration is effectively prolonged, the self-discharge rate is reduced, the safety coefficient is improved and the like, and the carbon fluoride material can be applied to the fields of electronic appliances such as electronic computers, clock cameras, integrated circuit memories and the like, medical treatment, military affairs and the like.

The reported methods for preparing carbon fluoride materials can be mainly classified into two methods: chemical and physical methods. The chemical method is a method using a reaction between graphene or a carbon nanotube and a fluorinating agent, a graphene oxide fluorination method, a method of exfoliating graphite, or the like. Due to F₂Expensive and difficult to handle, and many researchers have improved it by reacting carbon materials with XeF at room temperature₂Or CF₄And the like to prepare a carbon fluoride material. However, these fluorinating agents are toxic, not easy to obtain and have serious environmental pollution, and such reactions have high requirements on equipment and experimental conditions. The physical methods can be further classified into liquid phase exfoliation and mechanical exfoliation, i.e., the fluorinated graphene and the fluorinated carbon nanotube are prepared by liquid phase exfoliation or mechanical exfoliation of the fluorinated graphite and the fluorinated carbon nanotube. This method has low yield, high loss, and is mostly a small size sheet. At present, the research on fluorinated graphene and fluorinated carbon nanotubes is still in the initial stage, and the preparation method is not mature and large-scale preparation is not realized, so that the preparation method is limited in many application fields. Therefore, it is very important to find a simple, convenient and fast method suitable for large-scale preparation of fluorinated graphene and fluorinated carbon nanotubes.

Disclosure of Invention

In order to solve the problems in the prior art, the invention aims to provide a preparation method of fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content, and the synthesis method has the advantages of low equipment requirement, strong operability, simple process, less environmental pollution and easy large-scale production.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a preparation method of fluorinated graphene and fluorinated carbon nanotubes with controllable fluorine content comprises the steps of adding graphene and 1, 4-diiodoperfluorobutane or adding carbon nanotubes and 1, 4-diiodoperfluorobutane into an ampoule bottle, uniformly mixing, then carrying out vacuum pumping under the freezing condition of liquid nitrogen, and finally calcining to obtain the fluorinated graphene or the fluorinated carbon nanotubes.

The invention further improves the following steps: the fluorine atom content of the fluorinated graphene is 0.01-50%.

The invention further improves the following steps: the fluorine atom content of the fluorinated carbon nanotube is 0.01-50%.

The invention further improves the following steps: the calcination temperature is 200-500 ℃, and the calcination time is 0.1-48 hours.

The invention further improves the following steps: the calcination temperature was 360 ℃ and the calcination time was 1 hour.

The invention further improves the following steps: the temperature is raised from room temperature to 200-500 ℃ at a temperature rise rate of 5 ℃/min.

The invention further improves the following steps: and after calcination, dispersing the calcined product in an organic solvent, washing and drying to obtain the fluorinated graphene or the fluorinated carbon nanotube.

The invention further improves the following steps: the organic solvent is ethanol, methanol, acetone, dichloromethane, chloroform, carbon tetrachloride, tetrahydrofuran, acetonitrile or ethyl acetate.

Compared with the prior art, the invention has the following beneficial effects: the synthesis method has low requirements on equipment and strong operability; the fluorinating agent adopted by the invention is 1, 4-diiodoperfluorobutane, compared with F₂、XeF₂HF and other fluorinating agents with low toxicity and easy mass production, and fluorine of the fluorination product can be adjusted by adjusting the ratio of carbon to fluorineThe fluorine content of the graphene and the carbon fluoride nanotube is reduced, the thickness of the synthesized graphene fluoride and the carbon fluoride nanotube is small, and the yield is up to 90%. Has wider application prospect in the fields of anticorrosive coatings, lithium batteries and the like. The method synthesizes the fluorinated graphene and the fluorinated carbon nanotube through a gas-solid reaction, has low requirement on equipment, small toxicity of raw materials, simple process, strong operability and controllable fluorine content of the product. When the atomic proportion of fluorine in the fluorinated graphene and the fluorinated carbon nanotube is lower than 50%, the fluorine element in the 1, 4-diiodoperfluorobutane can quantitatively react with the graphene or the carbon nanotube to generate the fluorinated graphene and the fluorinated carbon nanotube with stoichiometric ratio.

Drawings

The invention is further illustrated with reference to the following figures in connection with embodiments.

Fig. 1 is a transmission electron microscope image of fluorinated graphene synthesized in example 1 of the present invention.

Fig. 2 is a graph showing fluorine contents of fluorinated graphene synthesized at different reaction times in examples 2 to 5 of the present invention.

Fig. 3 is an X-ray photoelectron spectrum of fluorinated graphene with different fluorocarbon ratios synthesized in examples 6 to 9 of the present invention.

FIG. 4 is an X-ray photoelectron spectrum of the fluorinated carbon nanotube synthesized in example 10 of the present invention.

FIG. 5 is a scanning electron micrograph of fluorinated carbon nanotubes synthesized in example 10 of the present invention.

Detailed Description

The present invention will be described in detail with reference to the accompanying drawings.

The invention relates to a preparation method of a fluorinated graphene material with low toxicity and adjustable fluorine content, which is characterized by comprising the following steps: the method comprises the following steps:

(1) uniformly mixing a precursor graphene or a carbon nano tube and 1, 4-diiodoperfluorobutane in an ampoule bottle in a certain amount;

(2) freezing the mixture in liquid nitrogen and vacuumizing;

(3) sealing the ampoule bottle in a vacuum state by using a gas spray gun, and calcining the ampoule bottle in a muffle furnace at a certain temperature;

(4) adding an organic solvent for ultrasonic dispersion, washing, filtering, drying and grinding to obtain the fluorinated graphene or fluorinated carbon nanotube.

In the step (1), the fluorinating reagent is 1, 4-diiodoperfluorobutane.

In the step (3), the calcination temperature of the reaction product in the muffle furnace is 200-500 ℃, and the time is 0.1-48 h.

In the step (4), the organic solvent may be ethanol, methanol, acetone, dichloromethane, chloroform, carbon tetrachloride, tetrahydrofuran, acetonitrile, or ethyl acetate.

The fluorine atom content of the fluorinated graphene prepared by the method is 0.01-50%, and the fluorine atom content of the fluorinated carbon nanotube is 0.01-50%. When the atomic proportion of fluorine in the fluorinated graphene and the fluorinated carbon nanotube is lower than 50%, the fluorine element in the 1, 4-diiodoperfluorobutane can quantitatively react with the graphene or the carbon nanotube to generate the fluorinated graphene and the fluorinated carbon nanotube with stoichiometric ratio. When 1, 4-diiodoperfluorobutane is used as a fluorinating agent, the fluorine atom content in the target product can be within the range of 0.01-50%.

The technical scheme of the invention is further explained by combining specific examples. It is to be understood that the following examples are only illustrative and explanatory of the present invention and should not be construed as limiting the scope of the present invention. All the technologies realized based on the above-mentioned contents of the present invention are covered in the protection scope of the present invention.

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs.

Example 1

Weighing 5mg of graphene and 47.3mg of 1, 4-diiodoperfluorobutane (the ratio of carbon to fluorine is 1:2) and mixing the graphene and the 1, 4-diiodoperfluorobutane in an ampoule bottle, freezing and vacuumizing by liquid nitrogen, uniformly sealing the mixture along three directions by a gas spray gun, placing the obtained mixture in a muffle furnace, heating to 360 ℃ at the speed of 5 ℃ per minute, and calcining for 1 hour.

And (3) taking out the ampoule bottle after the reaction is finished, dispersing the obtained product into an absolute ethyl alcohol solution, performing ultrasonic dispersion, washing and filtering until the filtrate is clear, and drying to obtain a final sample, namely 4.33mg of the fluorinated graphene.

Example 2

Weighing 2.5mg of graphene and 23.65mg of 1, 4-diiodoperfluorobutane (the fluorocarbon ratio of the graphene to the diiodoperfluorobutane is 1:2), mixing the graphene and the diiodoperfluorobutane in an ampoule bottle, freezing the mixture by using liquid nitrogen, vacuumizing the mixture, uniformly sealing the mixture along three directions by using a gas spray gun, putting the mixture in a muffle furnace, heating the mixture to 360 ℃ at the speed of 5 ℃ per minute, and respectively calcining the mixture for 0.5 hour.

And after the reaction is finished, taking out the ampoule bottle, dispersing the obtained product into an absolute ethyl alcohol solution, performing ultrasonic dispersion, washing and filtering until the filtrate is clear, and drying, wherein the obtained calcination time is 0.5 hour, and the mass of the obtained final sample fluorinated graphene is 2.308 mg.

Example 3

Unlike example 2 in which the time for the two calcinations was 1 hour, the final sample fluorinated graphene mass obtained was 2.289 mg. The rest is the same as in example 2.

Example 4

Unlike example 2 in which the two-calcination time was 2 hours, the final sample fluorinated graphene mass obtained was 2.149 mg.

The rest is the same as in example 2.

Example 5

Unlike example 2 in which the time for the two calcinations was 8 hours, the final sample fluorinated graphene mass obtained was 2.336 mg.

The rest is the same as in example 2.

Example 6

2.5mg of graphene and 23.65mg of 1, 4-diiodoperfluorobutane (the fluorocarbon ratio of the two is 1:2) are weighed respectively and mixed in an ampoule bottle. Freezing with liquid nitrogen, vacuumizing, uniformly sealing in three directions with a gas spray gun, placing the obtained mixture in a muffle furnace, heating to 360 ℃ at the speed of 5 ℃ per minute, and calcining for one hour.

Taking out the ampoule bottle after the reaction is finished, dispersing the obtained product into an absolute ethyl alcohol solution, performing ultrasonic dispersion, washing and filtering until the filtrate is clear, and drying to obtain a final sample with the carbon-fluorine ratio of 1:2, wherein the mass of the fluorinated graphene is 2.367mg, and the fluorine atom content is 47.1%.

Example 7

The difference from example 6 is that 10mg of graphene and 15mg of 1, 4-diiodoperfluorobutane (the fluorocarbon ratio of the two is 3:1) are weighed, and finally the mass of the sample fluorinated graphene with the fluorocarbon ratio of 3:1 is 9.072mg, and the fluorine atom content is 11.1%.

The rest was the same as in example 6.

Example 8

The difference from example 6 is that 40mg of graphene, 30mg of 1, 4-diiodoperfluorobutane and 40mg of graphene are weighed (the fluorocarbon ratio of the two is 6:1, and finally the mass of the sample fluorinated graphene with the fluorocarbon ratio of 6:1 is 37.662mg, and the fluorine atom content is 9.97%.

The rest was the same as in example 6.

Example 9

The difference from example 6 is that 15mg of 1, 4-diiodoperfluorobutane (the fluorocarbon ratio of the two is 12:1) is weighed, and the mass of the sample fluorinated graphene with the fluorocarbon ratio of 12:1 is 38.527mg and the fluorine atom content is 1.15% finally.

The rest was the same as in example 6.

Example 10

Weighing 10mg of carbon nanotube and 94.55mg of 1, 4-diiodoperfluorobutane (the ratio of carbon to fluorine is 1:4) and mixing in an ampoule bottle, freezing by liquid nitrogen and vacuumizing, uniformly sealing by a gas spray gun along three directions, placing the obtained reactant in a muffle furnace, heating to 360 ℃ at the speed of 5 ℃ per minute, and calcining for 1 hour.

And taking out the ampoule bottle after the reaction is finished, dispersing the obtained product into an absolute ethyl alcohol solution, ultrasonically dispersing and washing until the filtrate is clear, and drying to obtain a final sample, namely 8.96mg of the carbon fluoride nanotube.

Example 11

2.5mg of graphene and 1, 4-diiodoperfluorobutane (the ratio of carbon to fluorine is 1:1) are weighed respectively and mixed in an ampoule bottle. Freezing with liquid nitrogen, vacuumizing, uniformly sealing in three directions with a gas spray gun, placing the mixture in a muffle furnace, heating to 200 deg.C at 5 deg.C per minute, and calcining for 48 hr.

And (3) taking out the ampoule bottle after the reaction is finished, dispersing the obtained product into acetone, ultrasonically dispersing, washing and filtering until the filtrate is clear, and drying to obtain the final sample fluorinated graphene with the carbon-fluorine ratio of 1: 1.

Example 12

2.5mg of graphene and 1, 4-diiodoperfluorobutane (the ratio of carbon to fluorine is 1:4) are weighed respectively and mixed in an ampoule bottle. Freezing with liquid nitrogen, vacuumizing, uniformly sealing in three directions with a gas spray gun, placing the mixture in a muffle furnace, heating to 500 deg.C at 5 deg.C per minute, and calcining for 0.1 hr.

And (3) taking out the ampoule bottle after the reaction is finished, dispersing the obtained product into chloroform, ultrasonically dispersing, washing and filtering until the filtrate is clear, and drying to obtain the final sample fluorinated graphene with the carbon-fluorine ratio of 1: 4.

The organic solvent in the present invention may also be methanol, dichloromethane, carbon tetrachloride, tetrahydrofuran, acetonitrile or ethyl acetate.

Fig. 1 is a transmission electron microscope image of the fluorinated graphene synthesized in example 1 of the present invention, and it can be seen from fig. 1 that the synthesized product is ultra-thin sheet-like, soft and highly transparent.

Fig. 2 shows the fluorine atom content of the fluorinated graphene corresponding to different reaction times in examples 2 to 5 of the present invention, and as can be seen from fig. 2, the reaction time is 0.5 hour, the fluorine atom content of the fluorinated graphene is 12.35%, the reaction time is 1 hour, the fluorine atom content of the fluorinated graphene is up to 47.1%, the reaction time is 2 hours, the fluorine atom content is reduced to 19.97%, and the reaction time is 8 hours, the fluorine atom content is increased to 27.61%, but the reaction time is extended to 24 hours, and the fluorine atom content is reduced. In conclusion, the fluorine atom content tends to decrease with the reaction time.

When the atomic proportion of fluorine in the fluorinated graphene and the fluorinated carbon nanotube is lower than 50%, the fluorine element in the 1, 4-diiodoperfluorobutane can quantitatively react with the graphene or the carbon nanotube to generate the fluorinated graphene and the fluorinated carbon nanotube with stoichiometric ratio.

Fig. 3 is an X-ray photoelectron spectrum of fluorinated graphene with different fluorocarbon ratios synthesized in examples 6 to 9 of the present invention. It can be seen from FIG. 3 that the fluorine content is gradually decreased when the fluorocarbon ratio is 1:2, 3:1, 6:1 and 12:1, indicating that controlling the fluorocarbon ratio is effective to adjust the change in fluorine content.

Fig. 4 is an X-ray photoelectron spectrum of the fluorinated carbon nanotube synthesized in example 10 of the present invention, and it can be seen from fig. 4 that fluorine atoms are successfully doped on the carbon nanotube, and the fluorine content reaches 5.58%.

FIG. 5 is a scanning electron micrograph of the fluorinated carbon nanotubes synthesized in example 10 of the present invention, and it can be seen from FIG. 5 that the fluorinated carbon nanotubes are mainly distributed in a tubular shape, and the surface of the fluorinated carbon nanotubes becomes rough due to the formation of carbon fluoride on the surface.