阅读说明：本技术 一种活化二维氮掺杂类石墨烯的方法 (Method for activating two-dimensional nitrogen-doped graphene ) 是由 任斌 许跃龙 王莎莎 翟作昭 张利辉 刘振法 田志 桂鉴臣 于 2021-09-07 设计创作，主要内容包括：本发明公开了一种活化二维氮掺杂类石墨烯的方法,包括以下步骤：(1)氮掺杂类石墨烯合成：将三聚氰胺、氯化铵、聚乙烯吡咯烷酮混合后煅烧,得到黑色固体材料,即为氮掺杂类石墨烯；(2)合成工艺：向所述氮掺杂类石墨烯中加入硫酸镁进行混合,将混合材料置于马弗炉中进行煅烧,得到黑白相间的材料；(3)洗涤：将黑白相间的材料置于含有蒸馏水的烧杯中浸泡、抽滤,得到黑色固体材料,即可。本发明提供的活化二维氮掺杂类石墨烯的方法,整个处理过程具有绿色,经济、高效的优点,解决了常见的活化方法低效、高耗能、环境污染的缺点。(The invention discloses a method for activating two-dimensional nitrogen-doped graphene, which comprises the following steps: (1) synthesizing nitrogen-doped graphene: mixing melamine, ammonium chloride and polyvinylpyrrolidone, and calcining to obtain a black solid material, namely the nitrogen-doped graphene; (2) the synthesis process comprises the following steps: adding magnesium sulfate into the nitrogen-doped graphene for mixing, and placing the mixed material into a muffle furnace for calcining to obtain a black-white material; (3) washing: and (3) soaking the black-white material in a beaker containing distilled water, and performing suction filtration to obtain a black solid material. The method for activating the two-dimensional nitrogen-doped graphene provided by the invention has the advantages of environmental friendliness, economy and high efficiency in the whole treatment process, and overcomes the defects of low efficiency, high energy consumption and environmental pollution of a common activation method.)

1. A method for activating two-dimensional nitrogen-doped graphene is characterized by comprising the following steps:

(1) synthesizing nitrogen-doped graphene: mixing melamine, ammonium chloride and polyvinylpyrrolidone, and calcining to obtain a black solid material, namely the nitrogen-doped graphene;

(2) the synthesis process comprises the following steps: adding magnesium sulfate into the nitrogen-doped graphene for mixing, and placing the mixed material into a muffle furnace for calcining to obtain a black-white material;

(3) washing: and (3) soaking the black-white material in a beaker containing distilled water, and performing suction filtration to obtain a black solid material.

2. The method for activating two-dimensional nitrogen-doped graphene according to claim 1, wherein the mass ratio of melamine to ammonium chloride to polyvinylpyrrolidone in step (1) is 1:1: 1.

3. The method for activating two-dimensional nitrogen-doped graphene-like according to claim 1, wherein the calcination temperature in step (1) is 950 ℃ and the calcination time is 4 h.

4. The method for activating two-dimensional nitrogen-doped graphene according to claim 1, wherein the mass ratio of the nitrogen-doped graphene to magnesium sulfate in the step (2) is (1-2): (2-1).

5. The method of claim 1 or 4, wherein the mass ratio of the nitrogen-doped graphene to magnesium sulfate in the step (2) is 1: 1.

6. the method for activating two-dimensional nitrogen-doped graphene-like according to claim 1, wherein the calcination temperature in the step (2) is 600 ℃ and the calcination time is 1 h.

7. The method for activating two-dimensional nitrogen-doped graphene-like according to claim 1, wherein the soaking time in the step (3) is 30-240 min.

8. The method for activating two-dimensional nitrogen-doped graphene-like according to claim 1, wherein the calcination process in step (1) and step (2) is performed in an air atmosphere.

Technical Field

The invention relates to the technical field of chemical material preparation, in particular to a method for activating two-dimensional nitrogen-doped graphene.

Background

In the prior art, the activated two-dimensional carbon material is mainly treated by a physical method and a chemical method. The physical method mainly adopts water vapor or carbon dioxide as a physical activating agent, but the physical method for activating the two-dimensional carbon material has the phenomena of low activation efficiency and overhigh activation temperature, so the treatment cost is overhigh in the practical application process; the chemical method mainly utilizes KOH as a chemical activator, although the specific surface area of the material can be obviously improved, and the related performance of the material is further improved, the process not only needs high temperature (more than 800 ℃), but also the strong base does not meet the policy of green production at the present stage, and in addition, the doping content of heteroatoms is reduced by KOH activation, which is not beneficial to further improvement of the performance of the material.

Therefore, how to provide an efficient, green and economical method for activating a two-dimensional carbon material is a problem to be solved by those skilled in the art.

Disclosure of Invention

In view of the above, the invention provides a method for activating two-dimensional nitrogen-doped graphene, the whole treatment process has the advantages of being green, economical and efficient, and the defects of low efficiency, high energy consumption and environmental pollution of a common activation method are overcome.

In order to achieve the purpose, the invention adopts the following technical scheme:

the method for activating the two-dimensional nitrogen-doped graphene comprises the following steps

(1) Synthesizing nitrogen-doped graphene: mixing melamine, ammonium chloride and polyvinylpyrrolidone, and calcining to obtain a black solid material, namely the nitrogen-doped graphene;

(2) the synthesis process comprises the following steps: adding magnesium sulfate into the nitrogen-doped graphene for mixing, and placing the mixed material into a muffle furnace for calcining to obtain a black-white material;

the magnesium ions containing the hydrate are firstly adsorbed on the surface of the carbon material containing the hydrophilic group, water in the magnesium sulfate is gradually evaporated to form water vapor along with the temperature rise, and the water vapor can penetrate into the interlayer of the two-dimensional material, so that the mass transfer of the magnesium sulfate between the layers is facilitated, the bound water of the magnesium sulfate is gradually reduced along with the further temperature rise, magnesium sulfate particles between the layers are agglomerated and grown, the interlayer spacing of the material is enlarged, and the two-dimensional material is prevented from being stacked again.

(3) Washing: and (3) soaking the black-white material in a beaker containing distilled water, and performing suction filtration to obtain a black solid material.

The specific surface area of the activated material prepared by the method can reach 1050m at most²The particles are uniform in morphology and present a three-dimensional coral-like pore structure.

Preferably, in the method for activating two-dimensional nitrogen-doped graphene, the mass ratio of melamine to ammonium chloride to polyvinylpyrrolidone in step (1) is 1:1: 1.

Preferably, in the method for activating two-dimensional nitrogen-doped graphene, in the step (1), the calcination temperature is 950 ℃ and the calcination time is 4 hours.

Preferably, in the above method for activating two-dimensional nitrogen-doped graphene, the mass ratio of the nitrogen-doped graphene to magnesium sulfate in step (2) is (1-2): (2-1).

Preferably, in the method for activating two-dimensional nitrogen-doped graphene, the mass ratio of the nitrogen-doped graphene to magnesium sulfate in step (2) is 1: 1.

preferably, in the method for activating two-dimensional nitrogen-doped graphene, in the step (2), the calcination temperature is 600 ℃ and the calcination time is 1 h.

Preferably, in the above method for activating two-dimensional nitrogen-doped graphene, the soaking time in step (3) is 30-240min to remove magnesium sulfate adsorbed on the material.

Preferably, in the method for activating two-dimensional nitrogen-doped graphene, the calcination process in step (1) and step (2) is performed in an air atmosphere.

According to the technical scheme, compared with the prior art, the invention discloses the method for activating the two-dimensional nitrogen-doped graphene, which has the following beneficial effects: the magnesium sulfate is used as an activating agent, the two-dimensional nitrogen-doped graphene material is activated at a milder calcining temperature, the specific surface area of the activated material is remarkably improved compared with that of an unactivated two-dimensional carbon material, the heteroatom doping amount is not obviously changed, and the method has the characteristics of high efficiency, greenness and economy.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is a SEM and TEM image of examples 1-3 and comparative example 1, wherein A, D corresponds to example 1, B, E corresponds to example 2, C, F corresponds to example 3, and G, H corresponds to comparative example 1.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

(1) Synthesizing nitrogen-doped graphene: mechanically mixing melamine, ammonium chloride and polyvinylpyrrolidone according to the mass ratio of 1:1:1, and calcining for 4 hours at 950 ℃ in the air atmosphere to obtain a black solid material, namely a nitrogen-doped graphene material;

(2) the synthesis process comprises the following steps: adding magnesium sulfate into the synthesized nitrogen-doped graphene material, wherein the mass ratio of the nitrogen-doped graphene material to the magnesium sulfate is 2:1, uniformly mixing, and calcining in a 600 ℃ muffle furnace for 1h in the air atmosphere to obtain a black-and-white material;

(3) washing: soaking black and white materials in a beaker containing distilled water for 30min, and vacuum filtering to obtain black solid material.

Example 2

(1) Synthesizing nitrogen-doped graphene: mechanically mixing melamine, ammonium chloride and polyvinylpyrrolidone according to the mass ratio of 1:1:1, and calcining for 4 hours at 950 ℃ in the air atmosphere to obtain a black solid material, namely a nitrogen-doped graphene material;

(2) the synthesis process comprises the following steps: adding magnesium sulfate into the synthesized nitrogen-doped graphene material, wherein the mass ratio of the nitrogen-doped graphene material to the magnesium sulfate is 1:1, uniformly mixing, and calcining in a 600 ℃ muffle furnace for 1h in the air atmosphere to obtain a black-and-white material;

(3) washing: soaking black and white materials in a beaker containing distilled water for 30min, and vacuum filtering to obtain black solid material.

Example 3

(1) Synthesizing nitrogen-doped graphene: mechanically mixing melamine, ammonium chloride and polyvinylpyrrolidone according to the mass ratio of 1:1:1, and calcining for 4 hours at 950 ℃ in the air atmosphere to obtain a black solid material, namely a nitrogen-doped graphene material;

(2) the synthesis process comprises the following steps: adding magnesium sulfate into the synthesized nitrogen-doped graphene material, wherein the mass ratio of the nitrogen-doped graphene material to the magnesium sulfate is 1:2, uniformly mixing, and calcining in a 600 ℃ muffle furnace for 1h in the air atmosphere to obtain a black-and-white material;

(3) washing: soaking black and white materials in a beaker containing distilled water for 30min, and vacuum filtering to obtain black solid material.

Comparative example 1

(1) Synthesizing nitrogen-doped graphene: mechanically mixing melamine, ammonium chloride and polyvinylpyrrolidone according to the mass ratio of 1:1:1, and calcining for 4 hours at 950 ℃ in the air atmosphere to obtain a black solid material, namely a nitrogen-doped graphene material;

(2) washing: and (3) soaking the nitrogen-doped graphene material in a beaker containing distilled water for 30min, and then performing suction filtration to obtain a black solid material.

The specific surface area of the products obtained in examples 1 to 3 and comparative example 1 was measured, and the results are shown in Table 1:

TABLE 1

	Example 1	Example 2	Example 3	Comparative example 1
					Specific surface area m2/g	869	1050	905	755
Pore volume cm3/g	0.714	0.821	0.750	0.61

The embodiments in the present description are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other. For the scheme disclosed by the embodiment, the scheme corresponds to the method disclosed by the embodiment, so that the description is simple, and the relevant points can be referred to the method part for description.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.