CN112194119A

CN112194119A - Method for synthesizing three-dimensional graphene from solid sugar

Info

Publication number: CN112194119A
Application number: CN202011087857.3A
Authority: CN
Inventors: 朱艳艳; 王静
Original assignee: Hebei Medical University
Current assignee: Hebei Medical University
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2021-01-08

Abstract

The invention discloses a method for synthesizing three-dimensional graphene from solid sugar, and belongs to the technical field of three-dimensional graphene synthesis. The method comprises mixing solid sugar and inorganic sodium salt; placing the mixture in a reactor protected by inert or reducing gas for reaction, and cooling to room temperature under the protection of the same atmosphere after the reaction to obtain a solid product; and washing, filtering and drying the solid product to obtain the aza-graphene product. The invention has the characteristics of no pollution, low cost, simple process and large-scale preparation.

Description

Method for synthesizing three-dimensional graphene from solid sugar

Technical Field

The invention belongs to the technical field of three-dimensional graphene synthesis, and particularly relates to a method for synthesizing three-dimensional graphene from solid sugar.

Background

Graphene is a two-dimensional carbon material, and has a wide application prospect in the fields of energy storage and conversion, electronic information, biosensing thereof and the like due to the outstanding characteristics of electricity, heat, mechanics and the like. However, in practical use, due to the strong pi-pi interaction, the graphene two-dimensional structure is easily stacked between layers, which causes the decrease of conductivity, specific surface area and active sites, resulting in the decrease of performance of the graphene-based device.

The three-dimensional graphene has a rich communicated pore structure and a high specific surface area, and can solve the problems of poor conductivity and the like caused by easy stacking of graphene. However, whether the large-scale production of the three-dimensional graphene can be realized is a key for restricting whether the three-dimensional graphene can be widely applied. The existing methods for preparing the three-dimensional graphene include a sol-gel method, a chemical corrosion method, a template method and the like. For example, the sol-gel method is to prepare three-dimensional graphene through a process of reducing or assembling and drying an aqueous solution of graphene oxide. The chemical etching method is to obtain the three-dimensional porous graphene by using a KOH activation method or a nitric acid oxidation etching method for the graphene oxide. The template method generally adopts a template such as foamed nickel, silicon dioxide or zeolite, and then adopts strong acid to remove the template, so as to synthesize the porous three-dimensional graphene. In the above methods, the sol-gel method and the chemical etching method involve complicated and tedious steps for preparing graphene oxide, and strong acid and strong base substances which pollute the environment are used in the chemical etching method and the template method, so that the existing techniques still face great challenges for realizing large-scale preparation of three-dimensional graphene. In addition, the cost and the source of the raw materials for preparing the three-dimensional graphene are also key factors influencing whether the three-dimensional graphene can be produced in a large scale and widely applied.

Disclosure of Invention

The invention aims to provide a method for synthesizing three-dimensional graphene in a large scale with low cost, no pollution and simple operation.

The method takes solid sugar and inorganic sodium salt (sodium carbonate, sodium chloride or sodium sulfate) which are wide in source and low in price as raw materials, the raw materials are not required to be pretreated, the three-dimensional graphene is synthesized in one step, the obtained graphene has a three-dimensional network structure, pi-pi stacking of the graphene can be effectively inhibited, the synthesized three-dimensional graphene has a large specific surface area, and the method has great advantages in large-scale preparation of the three-dimensional graphene.

The preparation method of the invention comprises the following steps:

(1) mixing solid sugar and inorganic sodium salt (the molar ratio of the three is 1: 0.1-20);

(2) placing the mixture in a reactor protected by inert or reducing gas for reaction, and cooling to room temperature under the protection of the same atmosphere after the reaction to obtain a solid product;

(3) and washing the solid product with water, filtering and drying to obtain a three-dimensional graphene product.

The solid sugar comprises glucose, arabinose, lactose, fructose, maltose, sucrose, xylose, mannose and sorbose.

The inorganic sodium salt is sodium carbonate, sodium chloride or sodium sulfate.

The inert atmosphere is argon or nitrogen.

The reducing atmosphere is hydrogen.

The mixing comprises mechanical grinding mixing or solution mixing (after solid sugar and inorganic sodium salt are respectively prepared into solution and mixed, the solvent is removed to obtain a solid mixture).

The reaction temperature is 300-1500 ℃.

The reaction time is 0.1-200 min.

The invention has the following advantages:

(1) the solid sugar and the inorganic sodium salt are used as raw materials, the raw materials are cheap and easy to obtain, pretreatment is not needed, and the cost is low.

(2) The synthesis process has the advantages of simple flow, simple and convenient operation, easy control, less influence factors and good repeatability.

(3) The synthesized three-dimensional graphene has a connected network structure.

(4) The inorganic sodium salt (sodium carbonate, sodium chloride or sodium sulfate) used can be recycled.

(5) The method is convenient for large-scale and large-scale synthesis of the three-dimensional graphene.

Drawings

Fig. 1 is a Scanning Electron Microscope (SEM) photograph of three-dimensional graphene according to example 1 of the present invention.

Fig. 2 is a Scanning Electron Microscope (SEM) photograph of three-dimensional graphene according to example 5 of the present invention.

Fig. 3 is a Scanning Electron Microscope (SEM) photograph of three-dimensional graphene according to example 7 of the present invention.

Detailed Description

Example 1

Mixing glucose and sodium carbonate according to a molar ratio of 1:8, and grinding uniformly by adopting a mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 1000 ℃ for 2 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 1.7 nm.

Example 2

Mixing lactose and sodium chloride at a molar ratio of 1:10, and grinding by mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 800 ℃ for 10 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 3 nm.

Example 3

Mixing fructose and sodium sulfate according to a molar ratio of 1:10, and grinding uniformly by adopting a mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 600 ℃ for 20 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 3.7 nm.

Example 4

Dissolving arabinose and sodium chloride in water respectively, then uniformly mixing the two solutions, and removing the solvent to obtain a mixed product of the arabinose and the sodium chloride, wherein the molar ratio of the arabinose to the sodium chloride is 1: 10). 2g of the mixture is placed in a reactor protected by hydrogen atmosphere, and the reaction is carried out for 30min at 1000 ℃. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 3 nm.

Example 5

Respectively dissolving xylose and sodium carbonate in water, uniformly mixing the two solutions, and removing the solvent to obtain a mixed product of xylose and sodium carbonate, wherein the molar ratio of the xylose to the sodium carbonate is 1: 15). 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 900 ℃ for 20 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 3.6 nm.

Example 6

And (3) respectively dissolving sucrose and sodium sulfate in water, uniformly mixing the two solutions, and removing the solvent to obtain a mixed product of arabinose and sodium sulfate, wherein the molar ratio of the sucrose to the sodium sulfate is 1: 8). 2g of the solution was placed in a reactor protected by nitrogen atmosphere and reacted at 700 ℃ for 50 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 3.2 nm.

Example 7

Dissolving maltose and sodium carbonate in water respectively, then uniformly mixing the two solutions, and removing the solvent to obtain a mixed product of maltose and sodium sulfate, wherein the molar ratio of the maltose to the sodium carbonate is 1: 10). 2g of the solution was placed in a reactor protected by nitrogen atmosphere and reacted at 1100 ℃ for 10 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 2.0 nm.

Example 8

Mixing sorbose and sodium sulfate at a molar ratio of 1:0.1, and grinding by mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 900 ℃ for 120 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 2.7 nm.

Example 9

Mixing glucose and sodium sulfate at a molar ratio of 1:15, and grinding by mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 800 ℃ for 100 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 2.3 nm.

Example 10

Mixing mannose and sodium chloride according to a molar ratio of 1:0.5, and grinding uniformly by adopting a mechanical grinding method. 2g of the solution was placed in a reactor protected by argon atmosphere and reacted at 900 ℃ for 5 min. And after the product is cooled, taking out the product, washing with deionized water, filtering, drying and collecting the product. SEM pictures show that the synthesized sample presents a connected network-like structure, and AFM pictures show that the thickness of the sample is about 2.8 nm.

Claims

1. A method for synthesizing three-dimensional graphene from solid sugar is characterized by comprising the following steps:

mixing solid sugar and inorganic sodium salt;

placing the mixture in a reactor protected by inert gas or reducing gas for reaction, and cooling to room temperature under the protection of the same atmosphere after the reaction to obtain a solid product;

and washing, filtering and drying the solid product to obtain a three-dimensional graphene product.

2. The method according to claim 1, wherein the solid sugar comprises glucose, arabinose, lactose, fructose, maltose, sucrose, xylose, mannose and sorbose.

3. The method for synthesizing three-dimensional graphene from solid sugar according to claim 1, wherein the inorganic sodium salt is sodium chloride, sodium carbonate or sodium sulfate.

4. The method for synthesizing three-dimensional graphene from solid sugar according to claim 1, wherein the molar ratio of the solid sugar to the inorganic sodium salt is 1: 0.1-20.

5. The method for synthesizing three-dimensional graphene from solid sugar according to claim 1, wherein the inert atmosphere is argon or nitrogen.

6. The method for synthesizing three-dimensional graphene from solid sugar according to claim 1, wherein the reducing atmosphere is hydrogen.

7. The method for synthesizing three-dimensional graphene from solid sugar according to claim 1, wherein the mixing comprises mechanical milling mixing or solution mixing.

8. The method for synthesizing three-dimensional graphene from solid sugar according to claim 7, wherein the solid sugar and the inorganic sodium salt are separately prepared into solutions and mixed, and the solvent is removed to obtain a solid mixture.

9. The method for synthesizing three-dimensional graphene from solid sugar as claimed in claim 1, wherein the reaction temperature is 600-1500 ℃, and the reaction time is 0.1-100 min.