阅读说明：本技术 碳点辅助合成多组分铁基纳米复合材料的制备方法 (Preparation method of carbon-point-assisted synthesis multi-component iron-based nanocomposite ) 是由 胡胜亮 李世嘉 常青 李宁 薛超瑞 杨金龙 于 2021-09-24 设计创作，主要内容包括：本发明提供一种碳点辅助合成多组分铁基纳米复合材料的制备方法,该方法将CDs作为一个强大的平台,与特定的前驱体/添加剂同时进行多种化学反应,凭借其表面反应活性,CDs在高温下主导铁离子向零价铁的转化,同时,零价铁与硫酸根和氨气反应形成新的相结构。本发明公开的碳点辅助合成多组分铁基纳米复合材料的制备方法中,所有的化学反应和成核过程都局限在CDs表面,可以有效抑制CDs之间晶核的生长和团聚,所得到的多组分铁基纳米复合材料可以同时活化H-(2)O-(2)和PS,可以不需要任何能源消耗的情况下,有效降解四环素类抗生素类染物。(The invention provides a preparation method of a carbon-point-assisted synthesis multi-component iron-based nanocomposite, which takes CDs as a powerful platform to simultaneously carry out multiple chemical reactions with a specific precursor/additive, and by virtue of the surface reaction activity of the CDs, the CDs lead the conversion of iron ions to zero-valent iron at high temperature, and simultaneously, the zero-valent iron reacts with sulfate radicals and ammonia gas to form a new phase structure. The invention discloses a preparation method of a carbon-point-assisted synthesis multi-component iron-based nanocompositeIn the method, all chemical reactions and nucleation processes are limited on the surfaces of CDs, the growth and agglomeration of crystal nuclei among CDs can be effectively inhibited, and the obtained multi-component iron-based nanocomposite can simultaneously activate H 2 O 2 And PS can effectively degrade tetracycline antibiotic pollutants without any energy consumption.)

1. The preparation method of the carbon-point-assisted synthesis multi-component iron-based nano composite material is characterized by comprising the following steps: the method comprises the following steps:

step 1, adding 0.1-0.15 g of carbon dot powder and 0.2224-0.3336 g of ferrous sulfate into 20mL of deionized water, and performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and 20-30 KHz frequency to obtain a carbon dot-ferrous sulfate mixed solution;

step 2, adding 20-40 mL of ammonia water with volume concentration of 25 v/v% into the carbon dot-ferrous sulfate mixed solution obtained in the step 1, performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and frequency of 20-30 KHz, then putting the mixed solution after ultrasonic dispersion into an electric heating air blast drying oven, and drying at 70-90 ℃ to obtain a dark brown solid;

step 3, fully grinding the dark brown solid obtained in the step 2 in a mortar for 0.25-0.5 h to obtain dark brown powder;

and 4, placing the dark brown powder obtained by grinding in the step 3 into a tubular furnace, calcining for 2-4 hours at 700-900 ℃ under the protection of argon, wherein the heating rate of the tubular furnace is 5-10 ℃/min, the argon flow is 20-40 sccm, and then naturally cooling the tubular furnace to room temperature to finally obtain the multi-component iron-based nanocomposite.

2. The method for preparing the carbon-point-assisted synthesis multi-component iron-based nanocomposite material according to claim 1, wherein the method comprises the following steps: the CDs powder is obtained by selectively etching coal pitch by adopting formic acid and hydrogen peroxide according to a method for preparing multicolor luminous adjustable carbon dots by utilizing the coal pitch disclosed in the patent ZL 201610534465.4.

3. The method for preparing the carbon-point-assisted synthesis multi-component iron-based nanocomposite material according to claim 1, wherein the method comprises the following steps: the ferrous sulfate is replaced by nickel sulfate and cobalt sulfate, so that the preparation of the multi-component nickel-based and cobalt-based nano composite material can be realized.

4. The method for preparing the carbon-point-assisted synthesis multi-component iron-based nanocomposite material according to claim 1, wherein the method comprises the following steps: the ferrous sulfate may be replaced with ferric sulfate.

Technical Field

The invention belongs to the field of new materials, and particularly relates to a preparation method of a multi-component iron-based nanocomposite material synthesized by carbon dots in an auxiliary manner.

Background

Nanocomposites combine two or more different components on a nanosystem, representing a bottom-up design strategy for designing advanced structures with superior performance and multi-functional integration. Such properties result from the fusion of different materials. Although a variety of nanocomposites have been synthesized, the combination and synergistic effects of which have been demonstrated in terms of their optical, electronic and catalytic properties, the preparation of hybrid materials with multiple components and controllable morphological dimensions remains a difficult and hot spot of current research.

As a non-toxic element quantum dot, Carbon Dots (CDs) are receiving increasing attention in the fields of bio-imaging, drug delivery, sensors, functional materials, pollutant degradation and catalysis, and the like, and the increasing popularity of carbon dots can also be verified by their fast, simple and cheap synthetic routes, scalability in mass production, and adjustable surface structures. Typically, CDs consist of a graphite core surrounded by oxygen-and/or nitrogen-containing groups, which give it unique chemical behavior with the surrounding environment, including recognition/binding, reactivity, redox, and the like. For example, specific CDs can be used to design probes by virtue of their different affinities for surface active groups of CDs, and can be used to sensitively and selectively detect various metal ions, such as Fe^2+/3+，Cu²⁺，Hg^{2 +}，Pb²⁺And the like. These metal ions typically cause a change in the fluorescence of the CDs by surface adsorption and electron/energy transfer. In addition, the electron donor capability of CDs allows them to reduce noble metals or copper salts to elemental gold under photo-irradiation or hydrothermal reaction conditionsBelongs to the field of medicine. Thus, CDs appear as coupled components, acting synergistically to build hybrid nanostructures with properties that exceed those of the individual components. Moreover, CDs can be spliced into two-dimensional (2D) carbon nanosheets through surface group reaction at high temperature, thereby effectively preventing the growth and aggregation of surface-forming nuclei in other directions. By this method, various carbon-based hybrid materials are expected to be designed into a novel structure having excellent stability and activity. In addition to its essential role as a heterogeneous nucleating agent and support, the reactivity of CDs may also promote the formation of multiple components of the nanocomposite to promote its catalytic performance.

Disclosure of Invention

In order to further improve the catalytic performance of the nano composite material, the technical scheme adopted by the invention is as follows:

the preparation method of the carbon-point-assisted synthesis multi-component iron-based nanocomposite material comprises the following steps:

step 1, adding 0.1-0.15 g of carbon dot powder and 0.2224-0.3336 g of ferrous sulfate into 20mL of deionized water, and performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and 20-30 KHz frequency to obtain a carbon dot-ferrous sulfate mixed solution;

step 2, adding 20-40 mL of ammonia water with volume concentration of 25 v/v% into the carbon dot-ferrous sulfate mixed solution obtained in the step 1, performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and frequency of 20-30 KHz, then putting the mixed solution after ultrasonic dispersion into an electric heating air blast drying oven, and drying at 70-90 ℃ to obtain a dark brown solid;

step 3, fully grinding the dark brown solid obtained in the step 2 in a mortar for 0.25-0.5 h to obtain dark brown powder;

and 4, placing the dark brown powder obtained by grinding in the step 3 into a tubular furnace, calcining for 2-4 hours at 700-900 ℃ under the protection of argon, wherein the heating rate of the tubular furnace is 5-10 ℃/min, the argon flow is 20-40 sccm, and then naturally cooling the tubular furnace to room temperature to finally obtain the multi-component iron-based nanocomposite.

The CDs powder is obtained by selectively etching coal pitch by adopting formic acid and hydrogen peroxide according to a method for preparing multicolor luminous adjustable carbon dots by utilizing the coal pitch disclosed in the patent ZL 201610534465.4.

The ferrous sulfate is replaced by nickel sulfate and cobalt sulfate, so that the preparation of the multi-component nickel-based and cobalt-based nano composite material can be realized.

The ferrous sulfate may be replaced with ferric sulfate.

In the preparation method of the multi-component iron-based nanocomposite material synthesized by carbon points in an auxiliary manner, all chemical reactions and nucleation processes are limited on the surfaces of CDs, so that the growth and agglomeration of crystal nuclei among the CDs can be effectively inhibited, and the obtained multi-component iron-based nanocomposite material can simultaneously activate H₂O₂And PS can effectively degrade tetracycline antibiotic pollutants without any energy consumption.

Drawings

FIG. 1 is an X-ray diffraction pattern of a synthetic multicomponent iron-based nanocomposite material of the present invention;

FIG. 2 is a Raman spectrum of a synthetic multicomponent iron-based nanocomposite material of the present invention;

FIG. 3 is a high resolution TEM photograph of the multi-component Fe-based nanocomposite synthesized by the present invention;

FIG. 4 is a high resolution TEM photograph of the multi-component Fe-based nanocomposite synthesized by the present invention;

FIG. 5 shows the synthesis of multicomponent Fe-based nanocomposite N according to the present invention₂Adsorption-desorption isotherm curves;

FIG. 6 shows the synthesis of a multi-component iron-based nanocomposite activation H according to the present invention₂O₂Graph of reaction rate for degradation of Tetracycline (TC).

FIG. 7 shows the PS and H activation of the multi-component iron-based nanocomposite synthesized by the present invention₂O₂+ reaction rate diagram for PS degradation of Tetracycline (TC).

Detailed Description

The detailed technical scheme of the invention is described in the following with the accompanying drawings:

the preparation method of the carbon-point-assisted synthesis multi-component iron-based nanocomposite material comprises the following steps:

step 1, adding 0.1-0.15 g of carbon dot powder and 0.2224-0.3336 g of ferrous sulfate into 20mL of deionized water, and performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and 20-30 KHz frequency to obtain a carbon dot-ferrous sulfate mixed solution;

step 2, adding 20-40 mL of ammonia water with volume concentration of 25 v/v% into the carbon dot-ferrous sulfate mixed solution obtained in the step 1, performing ultrasonic dispersion for 0.5-1 h at 25-35 ℃ and frequency of 20-30 KHz, then putting the mixed solution after ultrasonic dispersion into an electric heating air blast drying oven, and drying at 70-90 ℃ to obtain a dark brown solid;

step 3, fully grinding the dark brown solid obtained in the step 2 in a mortar for 0.25-0.5 h to obtain dark brown powder;

and 4, placing the dark brown powder obtained by grinding in the step 3 into a tubular furnace, calcining for 2-4 hours at 700-900 ℃ under the protection of argon, wherein the heating rate of the tubular furnace is 5-10 ℃/min, the argon flow is 20-40 sccm, and then naturally cooling the tubular furnace to room temperature to finally obtain the multi-component iron-based nanocomposite.

The CDs powder is obtained by selectively etching coal pitch by adopting formic acid and hydrogen peroxide according to a method for preparing multicolor luminous adjustable carbon dots by utilizing the coal pitch disclosed in the patent ZL 201610534465.4.

The ferrous sulfate is replaced by nickel sulfate and cobalt sulfate, so that the preparation of the multi-component nickel-based and cobalt-based nano composite material can be realized.

The ferrous sulfate may be replaced with ferric sulfate.

Example 1

The preparation method of the carbon-point-assisted synthesis multi-component iron-based nanocomposite material comprises the following steps:

step 1 0.1g of carbon dot powder and 0.26g of ferrous sulfate (FeSO)₄·7H₂O) is added into 20mL of deionized water, and ultrasonic dispersion is carried out for 1h under the environment of 30 ℃ and 30KHz frequency, so as to obtain carbon dot-ferrous sulfate mixed solution;

step 2, adding 30mL of ammonia water with volume concentration of 25 v/v% into the carbon dot-ferrous sulfate mixed solution obtained in the step 1, performing ultrasonic dispersion for 1h in an environment with the temperature of 30 ℃ and the frequency of 30KHz, then putting the mixed solution after ultrasonic dispersion into an electric heating forced air drying oven, and drying in an environment with the temperature of 90 ℃ to obtain a dark brown solid;

step 3, fully grinding the black solid obtained in the step 2 in a mortar for 0.5h to obtain dark brown powder;

and 4, placing the dark brown powder obtained by grinding in the step 3 into a tubular furnace, calcining for 2 hours at 900 ℃ under the protection of argon, wherein the heating rate of the tubular furnace is 5 ℃/min, the flow of the argon is 20sccm, and then naturally cooling the tubular furnace to room temperature to finally obtain the multi-component iron-based nanocomposite. The multi-component iron-based nanocomposite prepared in the examples was characterized, and the X-ray diffraction pattern thereof was tested, as shown in fig. 1, which showed that the diffraction peaks with 2 θ of 30.0 °, 33.9 °, 43.9 ° and 53.3 ° and Fe₇S₈(JCPDS No.76-2308), two diffraction peaks at 44.7 DEG and 65.0 DEG corresponding to elemental Fe (JCPDS No.87-0721), and diffraction peaks at 43.6 DEG, 50.8 DEG and 74.6 DEG corresponding to FeN_0.0324(JCPDS No. 75-2127);

the Raman spectrum of the multi-component iron-based nanocomposite prepared in the test example is shown in FIG. 2, which is that FeNS @ PC is at 1336 and 1580cm^-1Two relatively broad and weak peaks were observed, indicating that porosity in the sample caused a relatively poor degree of graphitization;

the high-resolution transmission electron microscope photo of the multi-component iron-based nanocomposite prepared in the example is shown in FIG. 3, the center of the black core-shell structure is elementary iron, and the surrounding coating layer is Fe₇S₈And FeN_0.0324；

The high resolution transmission electron microscope photograph of the multi-component iron-based nanocomposite prepared in the example is shown in fig. 4, and the distances between different lattice stripes are measured to be 0.14nm, 0.26nm and 0.21nm, which respectively correspond to the (200) interplanar spacing of Fe, and the Fe₇S₈(203) interplanar spacing and FeN_0.0324(111) Interplanar spacing;

n of the multicomponent iron-based nanocomposite prepared in the examples₂The adsorption-desorption isotherm curve is shown in FIG. 5, which shows that the specific surface area of the sample reaches 209.39m²(ii)/g, illustrates formation of a porous carbon structure with excellent adsorption of contaminantsThe adhesive capacity;

tetracycline antibiotics are a broad-spectrum antibiotic produced by actinomycetes, and are widely used worldwide due to their low price and excellent anti-inflammatory, anti-apoptotic and neuroprotective effects. The discharge of undegraded tetracycline waste water into the environment can cause great pollution to the environmental water body. The multicomponent carbon-based composite nanomaterial can be prepared by activating hydrogen peroxide (H)₂O₂) Or sodium Persulfate (PS) generates hydroxyl free radicals and sulfate free radicals to degrade Tetracycline (TC) antibiotics. However, H can be simultaneously activated under different pH conditions₂O₂And degradation of tetracycline antibiotics by PS have been reported.

The multi-component iron-based nanocomposite material prepared in the example was used for degrading Tetracycline (TC), which activates H₂O₂Degradation of Tetracycline (TC) and activation of PS and H₂O₂The reaction rate graphs for + PS are shown in fig. 6 and fig. 7, respectively. Degradation experiments show that CDs can be used as a powerful platform to perform multiple chemical reactions with specific precursors/additives at the same time, and by virtue of the surface reaction activity of the CDs, the CDs dominate the conversion of iron ions to zero-valent iron at high temperature, and simultaneously, the zero-valent iron reacts with sulfate radicals and ammonia gas to form a new phase structure. All chemical reactions and nucleation processes are limited on the surfaces of CDs, and the growth and agglomeration of crystal nuclei between CDs are effectively inhibited. Therefore, the multi-component iron-based nanocomposite prepared in the examples uses elemental iron as a core, and Fe is wrapped around the elemental iron₇S₈And FeN_xThe obtained multi-component iron-based nano composite material can simultaneously activate H₂O₂And PS, the tetracycline antibiotic pollutants are effectively degraded, and no energy consumption is needed.