阅读说明：本技术 一种石墨烯氧化锌纳米复合材料的制备方法 (Preparation method of graphene zinc oxide nanocomposite ) 是由 朱伟 姜文静 蒋炎 黄荣庆 罗振扬 马宏明 于 2020-12-30 设计创作，主要内容包括：本发明公开了一种石墨烯氧化锌纳米复合材料的制备方法,属于石墨烯复合材料的制备技术领域。本发明是以氨基石墨烯为原料,以海绵为模板,制备得到三维氨基石墨烯,将所得三维氨基石墨烯置于锌盐溶液中进行晶体种植,得到三维氨基石墨烯原位生长纳米氧化锌。本发明的制备方法不仅克服了石墨烯和纳米氧化锌易团聚的问题,而且通过控制水热条件,控制纳米氧化锌的生长,制备得到的三维柔性石墨烯纳米氧化锌的光电、力学等多项性能可满足在不同领域的应用。(The invention discloses a preparation method of a graphene zinc oxide nano composite material, and belongs to the technical field of preparation of graphene composite materials. According to the method, amino graphene is used as a raw material, sponge is used as a template, the three-dimensional amino graphene is prepared, the obtained three-dimensional amino graphene is placed in a zinc salt solution for crystal planting, and the three-dimensional amino graphene in-situ growth nano zinc oxide is obtained. The preparation method provided by the invention not only overcomes the problem that graphene and nano zinc oxide are easy to agglomerate, but also controls the growth of nano zinc oxide by controlling hydrothermal conditions, and the prepared three-dimensional flexible graphene nano zinc oxide can meet the application requirements in different fields in various performances such as photoelectricity, mechanics and the like.)

1. The preparation method of the graphene-zinc oxide nanocomposite is characterized by taking amino graphene as a raw material and sponge as a template to prepare three-dimensional amino graphene, and placing the three-dimensional amino graphene in a zinc salt solution for crystal planting to obtain the three-dimensional amino graphene in-situ growth nano-zinc oxide.

2. The method of claim 1, wherein the sponge is a polyurethane sponge.

3. The preparation method of the graphene-zinc oxide nanocomposite material according to claim 1, wherein the specific method for preparing the three-dimensional amino graphene is as follows:

dispersing the aminated graphene in water according to the concentration of the aminated graphene being 0.5-5g/L, then immersing the aminated graphene in sponge for 5-30min, taking out the aminated graphene and pressurizing to remove redundant slurry, then drying, wherein the drying temperature is 60-80 ℃, the drying time is 30-90min, and repeatedly immersing for 3-5 times.

4. The method for preparing the graphene-zinc oxide nanocomposite as claimed in claim 3, wherein the method comprises dispersing the aminated graphene in deionized water by ultrasonic, shearing and emulsifying, wherein the ultrasonic power is 100-.

5. The method for preparing the graphene-zinc oxide nanocomposite material according to any one of claims 1 to 3, wherein the impregnation temperature of the sponge is normal temperature.

6. The method for preparing graphene-zinc oxide nanocomposite according to claim 3, wherein the sponge is pressed mechanically for 3 to 5 seconds.

7. The method for preparing the graphene-zinc oxide nanocomposite material according to claim 1, wherein the method for crystal planting comprises: firstly, seed crystals are pre-planted in the three-dimensional amino graphene, and then the nano zinc oxide grows in situ through hydrothermal reaction.

8. The preparation method of the graphene-zinc oxide nanocomposite material according to claim 1 or 7, wherein the specific method for crystal planting is as follows:

(1) soaking the three-dimensional amino graphene in a zinc salt alkaline solution for 20-60s, drying at the temperature of 120-150 ℃, repeating for 3-6 times for 5-20min to obtain the zinc-loaded three-dimensional amino graphene;

(2) soaking the three-dimensional amino graphene loaded with zinc seeds in a zinc salt alkaline solution to perform hydrothermal reaction, and growing a zinc oxide nanorod in situ;

(3) and washing and drying to obtain the graphene zinc oxide nano composite material.

9. The preparation method of the graphene zinc oxide nanocomposite material according to claim 8, wherein the zinc salt is zinc acetate or zinc nitrate, the concentration is 0.05-0.5mol/L, and the alkaline solution is one or a mixture of hexamethylenetetramine, urea and ammonia water.

10. The method for preparing graphene-zinc oxide nanocomposite according to claim 1, wherein the amino graphene is prepared by a method of Chinese patent 2018102122660.

Technical Field

The invention belongs to the technical field of preparation of graphene composite materials, and particularly relates to a preparation method of a graphene zinc oxide nano composite material.

Background

Graphene, which is a two-dimensional planar material having a honeycomb structure composed of carbon atoms, has attracted attention of many researchers since its discovery, and is widely used in various fields due to its excellent optical, electrical, and mechanical properties. Graphene can be used as an ideal nano material for preparing a composite material, and the excellent properties of graphene can be utilized to be compounded with other materials, so that the excellent properties of the material can be endowed. Therefore, graphene composite materials are a hot spot in the research of the present nanocomposite materials.

Zinc oxide is a wide band gap direct band gap II-VI semiconductor material, the valence band of which is composed of 2p state of O atom, and the conduction band is mainly composed of 4s state of Zn atom, and has many unique material properties. The zinc oxide is a wide-bandgap direct semiconductor with a forbidden band width of 3.37eV (at room temperature), so that the zinc oxide has a wide application prospect in the aspect of ultraviolet photoelectricity. The binding energy of the zinc oxide is as high as 60meV, which is far higher than room temperature ionization energy (26meV), and is much higher than that of other semiconductors, excitons are stable and can not be dissociated, so that the zinc oxide is easier to realize high-efficiency laser emission at room temperature, and is an ideal ultraviolet light-emitting device material. The zinc oxide also has stronger radiation damage resistance and is a potential space application material.

The Chinese patent 2019100846840 with publication date of 2019, 5 and 21 discloses a zinc oxide nanosheet array/three-dimensional foam graphene biosensor working electrode and a preparation method and application thereof, wherein a metallic nickel screen is used as a template, high-conductivity and defect-free three-dimensional foam graphene is synthesized by a chemical vapor deposition method, the zinc oxide nanosheet array with a high specific surface area is grown on the surface of the zinc oxide nanosheet array by a hydrothermal method, the zinc oxide nanosheet array can provide countless active points, and electrons of a reaction product are directly transferred to the graphene to realize rapid transfer of the electrons. However, the production cost of the technology is high, the process is complex, and the technology is not beneficial to the industrial production of products.

Disclosure of Invention

Aiming at the existing problems, the invention aims to provide a preparation method of a graphene zinc oxide nanocomposite material with low cost, simple and convenient process and excellent performance, and solves the problems of high production cost and complex process of the existing graphene zinc oxide nanocomposite material.

In order to solve the problems, the technical scheme adopted by the invention is as follows:

a preparation method of a graphene zinc oxide nano composite material comprises the steps of taking amino graphene as a raw material and sponge as a template to prepare three-dimensional amino graphene, placing the three-dimensional amino graphene in a zinc salt solution for crystal planting, and obtaining the three-dimensional amino graphene in-situ growth nano zinc oxide.

Further, the sponge is a polyurethane sponge.

Further, the specific method for preparing the three-dimensional amino graphene comprises the following steps:

dispersing the aminated graphene in water according to the concentration of the aminated graphene being 0.5-5g/L, then immersing the aminated graphene in sponge for 5-30min, taking out the aminated graphene and pressurizing to remove redundant slurry, then drying the aminated graphene at the drying temperature of 60-80 ℃ for 30-90min, and repeatedly immersing for 3-5 times.

Furthermore, the method of ultrasonic treatment, shearing treatment and emulsification is adopted when the aminated graphene is dispersed in the deionized water, wherein the ultrasonic power is 100-.

Further, the sponge was immersed at room temperature.

Furthermore, the sponge is pressed mechanically for 3-5 seconds.

Further, the crystal planting method comprises the following steps: firstly, seed crystals are pre-planted in the three-dimensional amino graphene, and then the nano zinc oxide grows in situ through hydrothermal reaction.

Further, the specific method for crystal planting comprises the following steps:

(1) soaking the three-dimensional amino graphene in a zinc salt alkaline solution for 20-60s, drying at the temperature of 120-150 ℃, repeating for 3-6 times for 5-20min to obtain the zinc-loaded three-dimensional amino graphene;

(2) soaking the three-dimensional amino graphene loaded with zinc seeds in a zinc salt alkaline solution for hydrothermal reaction, and growing zinc oxide nanorods in situ;

(3) and washing and drying to obtain the graphene zinc oxide nano composite material.

Furthermore, the zinc salt is zinc acetate or zinc nitrate, the concentration is 0.05-0.5mol/L, and the alkaline solution is one or a mixture of hexamethylene tetramine, urea and ammonia water.

Further, the amino graphene is prepared by adopting a method disclosed in Chinese patent 2018102122660.

Compared with the prior art, the invention has the beneficial effects that:

(1) according to the method, the graphene oxide is subjected to amino functionalization, so that the redispersion of graphene is facilitated, the agglomeration of the graphene is reduced, and the graphene is uniformly loaded on the upper surface of the framework of the sponge.

(2) According to the invention, the aminated graphene is loaded on the surface of the sponge, and the sponge matrix can provide a micropore channel for the material.

(3) Seed crystals are pre-planted in the three-dimensional porous graphene network structure, and then the growth of zinc oxide in the three-dimensional porous graphene network structure is regulated through hydrothermal condition control.

(4) The preparation method provided by the invention not only overcomes the problem that graphene and nano zinc oxide are easy to agglomerate, but also controls the growth of nano zinc oxide by controlling hydrothermal conditions, so that the prepared three-dimensional flexible graphene nano zinc oxide has good photoelectric properties, and can meet the application requirements in different fields. Compared with the single composite material prepared by graphene, zinc oxide and other methods, the composite material prepared by the method has more excellent performance, so that the composite material can be widely applied in various fields.

Drawings

Fig. 1 is a C element distribution diagram of the amino graphene on the surface of a three-dimensional sponge substrate in example 1;

fig. 2 is a N element distribution diagram of the amino graphene on the surface of the three-dimensional sponge substrate in example 1.

Detailed Description

The invention is further described with reference to specific examples.

The following examples and comparative examples all employ the amino graphene prepared according to example 1 of chinese patent 2018102122660.

The sponge is commercially available polyurethane sponge, and the sponge density is 18g/cm³。

The rest raw materials are all commercial industrial grade.

Example 1

A graphene zinc oxide nanocomposite is prepared by the following method:

taking amino graphene, preparing the amino graphene into 0.5g/L aqueous solution, carrying out ultrasonic treatment for 0.5h, carrying out ultrasonic power of 100W, carrying out shearing emulsification for 2h, and carrying out shearing emulsification at the rotating speed of 4500 r/min. Soaking sponge of 3cm by 1.5cm in the amino graphene solution for 60s at normal temperature, then mechanically extruding for 5s, drying at 60 ℃, and repeating for three times to obtain a three-dimensional amino graphene sponge net, wherein the loading capacity of the amino graphene is 14 mg.

The obtained three-dimensional graphene sponge net planting seed crystal comprises the following detailed steps: firstly, mixing 40mL of 0.1mol of zinc acetate and 40mL of 0.1mol of hexamethylenetetramine, soaking the three-dimensional graphene sponge in the mixture for 30s, then drying the mixture in a 120-degree oven, repeating the step for three times, and planting the seed crystal on the amino graphene sponge net.

And compounding zinc acetate ammonia water solution with equal molar ratio, mixing 45mL of 0.1mol zinc acetate solution and 45mL of 0.1mol ammonia water solution, immersing the three-dimensional graphene sponge in the mixture, carrying out hydrothermal reaction, and reacting for 4 hours at 100 ℃. After the reaction is finished, cooling to room temperature, taking out the three-dimensional graphene zinc oxide sponge material, drying at 60 ℃ to obtain flexible three-dimensional amino graphene nano zinc oxide sponge, and weighing to obtain the load capacity of the nano zinc oxide of 123 mg.

Example 2

A graphene zinc oxide nanocomposite is prepared by the following method:

taking amino graphene, preparing the amino graphene into 1g/L aqueous solution, carrying out ultrasonic treatment for 1h, carrying out ultrasonic power of 120W, carrying out shearing emulsification for 3h, and carrying out shearing emulsification at a rotating speed of 5000 r/min. Soaking sponge of 3cm by 1.5cm in the amino graphene solution at normal temperature for 40s, then mechanically extruding for 3s, drying at 60 ℃, and repeating for three times to obtain a three-dimensional amino graphene sponge net, wherein the loading capacity of the amino graphene is 16 mg.

The obtained three-dimensional graphene sponge net planting seed crystal comprises the following detailed steps: firstly, 40mL of 0.1mol zinc nitrate and 40mL of 0.1mol urea are mixed, the three-dimensional graphene sponge is soaked in the mixture for 30s, then the mixture is dried in a 120-degree oven, and the step is repeated for three times, so that the seed crystal is planted on the amino graphene sponge net.

And compounding a zinc nitrate urea solution with an equal molar ratio, mixing 45mL of 0.1mol zinc nitrate solution and 45mL of 0.1mol urea solution, immersing the three-dimensional graphene sponge in the mixture, carrying out hydrothermal reaction, and reacting for 6 hours at 80 ℃. After the reaction is finished, cooling to room temperature, taking out the three-dimensional graphene zinc oxide sponge material, drying at 60 ℃ to obtain flexible three-dimensional amino graphene nano zinc oxide sponge, and weighing to obtain the nano zinc oxide with the load of 119 mg.

Example 3

A graphene zinc oxide nanocomposite is prepared by the following method:

taking amino graphene, preparing the amino graphene into a 2g/L aqueous solution, carrying out ultrasonic treatment for 2h, carrying out ultrasonic power of 150W, carrying out shearing emulsification for 4h, and carrying out shearing emulsification at the rotating speed of 4000 r/min. Soaking sponge of 3cm by 1.5cm in the amino graphene solution for 20s at normal temperature, then mechanically extruding for 4s, drying at 60 ℃, and repeating for three times to obtain a three-dimensional amino graphene sponge net, wherein the loading capacity of the amino graphene is 15 mg.

The obtained three-dimensional graphene sponge net planting seed crystal comprises the following detailed steps: firstly, 40mL of 0.1mol zinc acetate and 40mL of 0.1mol urea are mixed, the three-dimensional graphene sponge is soaked in the mixture for 30s, then the mixture is dried in a 120-degree oven, and the step is repeated for three times, so that the seed crystal is planted on the amino graphene sponge net.

Compounding zinc acetate urea solution with equal molar ratio, mixing 45mL of 0.1mol zinc acetate solution and 45mL of 0.1mol urea solution, immersing the three-dimensional graphene sponge therein, carrying out hydrothermal reaction, and reacting for 5 hours at 90 ℃. After the reaction is finished, cooling to room temperature, taking out the three-dimensional graphene zinc oxide sponge material, drying at 60 ℃ to obtain flexible three-dimensional amino graphene nano zinc oxide sponge, and weighing to obtain 117mg of nano zinc oxide.

Comparative example 1

This comparative example is substantially the same as example 1 except that graphene oxide was directly supported on the surface of the sponge.

Comparative example 2

This comparative example is essentially the same as example 2, except that the aminographene is directly dispersed in an alkaline solution of zinc salt.

Comparative example 3

This comparative example is substantially the same as example 3 except that the aminographene is supported on the surface of the nickel mesh.

The graphene nano zinc oxide composite materials obtained in each example and comparative example are used as catalysts to carry out a photocatalytic degradation methylene blue test. The composite material was placed in 20mL of methylene blue solution with a concentration of 10mg/mL and irradiated with 500-xenon light, and the results are shown in Table 1.

The distribution of the amino graphene on the three-dimensional sponge body in example 1 is subjected to elemental analysis, fig. 1 is a C element distribution diagram of the amino graphene on the surface of the three-dimensional sponge body, and fig. 2 is an N element distribution diagram of the amino graphene on the surface of the three-dimensional sponge body. As can be seen from fig. 1 and 2, the C, N element is distributed relatively uniformly, and it is presumed that the amino graphene is uniformly distributed on the surface of the three-dimensional sponge matrix.

TABLE 1 photocatalytic results of samples obtained in examples and comparative examples

	Catalyst content (mg)	Methylene blue degradation time (min)
			Example 1	45	20min
Example 2	45	25min
			Example 3	44	37min
Comparative example 1	45	40min
			Comparative example 2	45	55min
Comparative example 3	45	27min

As can be seen from table 1, the effect of photocatalytic methylene blue of the three-dimensional aminated graphene nano zinc oxide sponge prepared by the method of the present invention is significantly improved, because the sponge matrix provides a microporous pore channel for the catalyst, the contact area of the catalyst is increased, and the catalytic degradation of the dye is facilitated, which cannot be achieved by a photocatalyst without a sponge matrix. Compared with a metal template, the sponge base material has the same effect, but effectively reduces the production cost and increases the flexibility of a sample.