Graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity and preparation method thereof
阅读说明：本技术 一种具有高紫外吸收特性和亲脂性的石墨烯量子点材料及其制备方法 (Graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity and preparation method thereof ) 是由 吴宥伸 和玲 潘爱钊 于 2019-09-04 设计创作，主要内容包括：本发明公开了一种具有高紫外吸收特性和亲脂性的石墨烯量子点材料及其制备方法,该制备方法以多羧酸分子的酯作为碳源,加热碳化制备出具有高紫外吸收和亲脂性特性的石墨烯量子点材料；使用的多羧酸分子的酯在常温或加热条件下为液态,且具有高沸点,利用这一特点,可通过简单的加热方式实现碳源的均匀碳化,无须使用任何溶剂,无溶剂碳化过程中对于加热气氛及碳化压力无特殊要求,碳化效率高且环境友好,并且防止了溶剂与碳源间可能存在的副反应,大幅简化了产物的分离纯化工艺,后续的反应过程中只需要通过分散和沉析处理,即可将粗产物纯化处理；制备出来的材料具有良好的亲脂性和高紫外吸收特性。(The invention discloses a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity and a preparation method thereof, wherein the preparation method takes ester of polycarboxylic acid molecules as a carbon source, and the graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity is prepared by heating and carbonizing; the used ester of the polycarboxylic acid molecule is liquid under normal temperature or heating condition and has high boiling point, by utilizing the characteristic, the uniform carbonization of the carbon source can be realized through a simple heating mode, no solvent is needed, no special requirements on heating atmosphere and carbonization pressure exist in the solvent-free carbonization process, the carbonization efficiency is high, the environment is friendly, the possible side reaction between the solvent and the carbon source is prevented, the separation and purification process of the product is greatly simplified, and the crude product can be purified only by dispersion and precipitation treatment in the subsequent reaction process; the prepared material has good lipophilicity and high ultraviolet absorption characteristics.)
1. A preparation method of a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity is characterized by comprising the following steps:
step 1, heating a carbon source, wherein the carbon source is an ester of a polycarboxylic acid molecule, and generating a crude product of a graphene quantum dot material;
step 2, cooling a crude product of the graphene quantum dot material, and dispersing the cooled product in a dispersion solvent to obtain a dispersion liquid A of the graphene quantum dots;
step 3, adding a precipitation reagent into the dispersion liquid A of the graphene quantum dots, centrifugally separating a precipitation product, and dispersing the centrifugal product into a dispersion solvent again to obtain a dispersion liquid B of the graphene quantum dots;
and 4, drying the dispersion liquid B of the graphene quantum dots to obtain the purified graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity.
2. The method for preparing a graphene quantum dot material with high ultraviolet absorption property and lipophilicity according to claim 1, wherein in the step 1, the ester of the polycarboxylic acid molecule is one of tributyl citrate, trioctyl citrate, triisooctyl citrate, tributyl acetylcitrate, trioctyl acetylcitrate, triisooctyl acetylcitrate, dimethyl malate, diethyl malate, diisopropyl malate, malic diisostearate, ascorbyl stearate and ascorbyl palmitate.
3. The method for preparing the graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity according to claim 1, wherein the heating temperature in the step 1 is 200-300 ℃.
4. The method for preparing the graphene quantum dot material with high ultraviolet absorption property and lipophilicity according to claim 1, wherein in the step 1, the carbon source is heated in a heating furnace, an electric heating sleeve or a microwave reactor, or heated by a thermal reflux method.
5. The method for preparing the graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity according to claim 1, wherein in the step 2 and the step 3, the dispersion solvent is ethanol or isopropanol.
6. The method for preparing a graphene quantum dot material with high ultraviolet absorption property and lipophilicity according to claim 1, wherein in the step 3, the precipitation reagent is deionized water or acetone.
7. The method for preparing the graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity according to claim 1, wherein in the step 3, the volume ratio of the dispersion liquid A of the graphene quantum dots to the precipitation reagent is 1: (3-10).
8. The method for preparing the graphene quantum dot material with the high ultraviolet absorption characteristic and the lipophilicity according to claim 1, wherein in the step 4, before the drying treatment of the graphene quantum dot dispersion liquid B, the steps 2 and 3 are repeated 3-5 times, and the repeatedly cleaned graphene quantum dot dispersion liquid B is dried.
9. A graphene quantum dot material with high ultraviolet absorption characteristics and lipophilicity, prepared by the preparation method of any one of claims 1 to 8.
10. The graphene quantum dot material with high ultraviolet absorption property and lipophilicity according to claim 9, wherein the particle size is 5-15 nm.
[ technical field ] A method for producing a semiconductor device
The invention belongs to the field of nano materials, and particularly relates to a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity and a preparation method thereof.
[ background of the invention ]
Ultraviolet radiation exists in sunlight and various artificial light sources, and strong ultraviolet radiation can cause aging and damage of polymer materials and also pose a threat to human health. The ultraviolet absorbent with high ultraviolet absorption characteristic is added in the material and the coating, so that the ultraviolet radiation can be effectively blocked, and the negative influence of the ultraviolet radiation can be reduced. At present, organic micromolecule ultraviolet absorbers, nano zinc oxide, nano titanium dioxide and other inorganic ultraviolet radiation resistant materials are widely applied, but the defects of low light and heat stability and uneven dispersion in solvents, resins and polymer materials still exist. In particular, the influence of the existing ultraviolet absorbers on human health and the environment is also receiving wide attention.
The graphene quantum dots are quasi-zero-dimensional graphene nano materials with the diameter less than 100 nanometers and composed of single-layer or 2-3 layers of carbon atoms. The graphene quantum dots have the characteristics of small particle size, large specific surface area and good light and heat stability, have unique photoelectric characteristics, and have important application in the fields of nano materials, sensing analysis, photoelectric materials and the like. The graphene quantum dot material has strong light absorption in a plurality of ultraviolet radiation wavelength ranges including UVA, UVB and UVC, has good biocompatibility, and has important potential application value in the technical field of ultraviolet radiation protection.
At present, the preparation strategies of graphene quantum dot materials can be divided into two types of top-down methods and bottom-up methods, wherein the top-down methods are that graphene oxide, graphite, coal and other materials are used as raw materials, the raw materials are decomposed and crushed through the action of strong oxidant, heating, ultrasound and the like, and the graphene quantum dots are obtained through separation and purification. The method from bottom to top is characterized in that micromolecules or polymers are used as raw materials, graphene quantum dots are obtained through high-temperature carbonization treatment, and controllable preparation of the graphene quantum dot material with a specific structure and a light-emitting characteristic can be achieved through selection of carbonized precursor raw materials and regulation and control of a carbonization process. However, the graphene quantum dot material prepared by the existing method often has more polar groups such as carboxyl and hydroxyl, and is difficult to be uniformly dispersed in a non-polar solvent and a polymer material. Meanwhile, most of the existing researches focus on the luminescence property of the graphene quantum dot, but an effective strategy for regulating and controlling the ultraviolet absorption property of the graphene quantum dot is lacked, so that the further application of the graphene quantum dot material as a high-efficiency environment-friendly ultraviolet absorbent is limited.
[ summary of the invention ]
The invention aims to overcome the problems in the prior art, and provides a graphene quantum dot material with high ultraviolet absorption property and lipophilicity and a preparation method thereof, so as to solve the problems that in the prior art, more solvents are used in the preparation process of the graphene quantum dot material, the prepared graphene quantum dot material is difficult to dissolve in nonpolar solvents and polymer materials, and the ultraviolet absorption property is poor.
In order to achieve the purpose, the invention adopts the following technical scheme to realize the purpose:
a preparation method of a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity comprises the following steps:
and 4, drying the dispersion liquid B of the graphene quantum dots to obtain the purified graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity.
The invention is further improved in that:
preferably, in
Preferably, in
Preferably, in
Preferably, in
Preferably, in
Preferably, in
Preferably, in
The graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity is prepared by the preparation method.
Preferably, the particle size is 5-15 nm.
Compared with the prior art, the invention has the following beneficial effects:
the invention discloses a preparation method of a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity, which takes ester of polycarboxylic acid molecules as a carbon source and prepares the graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity through polymerization and carbonization of carbon source molecules at high temperature; the ester of the used polycarboxylic acid molecule is liquid under normal temperature or heating condition and has high boiling point, and by utilizing the characteristics, the uniform carbonization of the carbon source can be realized through a simple heating mode without using any solvent, no special requirements on heating atmosphere and carbonization pressure exist in the solvent-free carbonization process, the carbonization efficiency is high, the environment is friendly, the possible side reaction between the solvent and the carbon source is prevented, the separation and purification process of the product is greatly simplified, and the crude product can be purified only through dispersion and precipitation treatment in the subsequent reaction process.
Furthermore, the selected ester of the polycarboxylic acid molecules has a higher boiling point, and can be heated to the carbonization temperature without boiling, so that the actual carbonization reaction temperature can be effectively increased, and the carbonization degree of the product can be improved.
Further, compared with the conventional solvent thermal method for preparing the graphene quantum dots, the method utilizes the ester of the liquid polycarboxylic acid molecules, so that the heating method can use a heating furnace, an electric heating jacket, a microwave reactor or a thermal reflux method, and has no special requirements on heating atmosphere, carbonization pressure and atmosphere.
Further, ethanol or isopropanol which has good solubility for both the polycarboxylate carbon source molecules and the graphene quantum dot products is selected as a dispersing solvent, and deionized water or acetone which can be miscible with the ethanol or isopropanol and can precipitate the graphene quantum dots is selected as a precipitating agent.
The invention also discloses a graphene quantum dot material with high ultraviolet absorption characteristic and lipophilicity, the graphene quantum dot material in the material is rich in ester edge groups, has good lipophilicity and high ultraviolet absorption characteristic, and realizes preparation of the high ultraviolet absorption graphene quantum dot material. The prepared graphene quantum dot material has abundant ester edge groups, so that the material can be uniformly and stably dispersed in various solvents, resins and polymers, and therefore, the graphene quantum dot material has good biocompatibility and environment-friendly characteristics, is safe and stable, and has outstanding advantages in the fields of textiles, food packaging, sun-screening cosmetics and the like. Verification shows that the graphene quantum dot material has an obvious crystallization structure and strong ultraviolet absorption characteristics, and shows excellent stability in long-term ultraviolet irradiation.
[ description of the drawings ]
Fig. 1 is a high-resolution transmission electron microscope photograph of a graphene quantum dot material prepared in example 2 of the present invention;
fig. 2 is an ultraviolet absorption spectrum of the graphene quantum dot material prepared in example 2 of the present invention;
fig. 3 is a fluorescence emission spectrum of the graphene quantum dot material prepared in example 2 of the present invention under 370nm excitation;
fig. 4 is an infrared spectrum of a graphene quantum dot material prepared in example 2 of the present invention;
fig. 5 is a photograph showing the dispersion of the graphene quantum dot material prepared in example 2 of the present invention in cyclohexane, toluene, dioxane, dichloromethane, and ethanol, respectively;
fig. 6 is a fluorescent photograph of the graphene quantum dot material prepared in example 2 of the present invention under 365 nm ultraviolet irradiation with cyclohexane, toluene, dioxane, dichloromethane, and ethanol solution, respectively.
[ detailed description ] embodiments
The invention is further described in detail with reference to the accompanying drawings and specific embodiments, and discloses a graphene quantum dot material with high ultraviolet absorption property and lipophilicity and a preparation method thereof, which specifically comprises the following steps:
And (2) placing a carbon source in a container, heating the carbon source in an air atmosphere, a nitrogen atmosphere or an argon atmosphere, and carrying out carbonization treatment, wherein the heat source is a resistance furnace, an electric heating jacket or a microwave reactor, or can be heated by using a thermal reflux method, the heating temperature is 200-300 ℃, and the carbon source is heated to obtain a brownish black product which is a crude product of the graphene quantum dot material.
The carbon source is ester of polycarboxylic acid molecules, specifically one of tributyl citrate, trioctyl citrate, triisooctyl citrate, tributyl acetylcitrate, trioctyl acetylcitrate, triisooctyl acetylcitrate, dimethyl malate, diethyl malate, diisopropyl malate, diisostearic malate, ascorbyl stearate and ascorbyl palmitate, and the adopted container is a high-temperature resistant container made of glass, quartz, ceramic or p-polyphenyl. In this step, the heating time is different depending on the ester of the polycarboxylic acid molecule used.
And 4, repeating the
The invention is further described with reference to specific examples.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：石墨烯气凝胶三维结构及其制备方法