Preparation method of large flake diameter graphite diacetylene powder material

Abstract

The application discloses a preparation method of a large-diameter graphite diacetylene powder material. The large-diameter (5-10 mu m) graphite diacetylene powder material with a two-dimensional nanosheet structure is prepared by adopting a substrate-free system combined with a microwave reaction. Unlike the graphite diacetylene film material prepared in the prior art, the graphite diacetylene powder material has a wider application in ion batteries, electrocatalysis, DNA detection and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of material preparation, and particularly relates to a preparation method of a large flake diameter graphdiyne powder material. BACKGROUND

[0002] With the continuous development of carbon materials, many new carbon allotropes have been discovered. In 1997, Haley et al. proposed a unique two-dimensional carbon allotrope-graphdiyne. It has a completely different chemical structure compared with graphene, which is composed of sp and sp 2 hybridized carbon atoms. Among the numerous members of the graphdiyne family, graphdiyne is the most stable material, which is connected by 1,3-diynyl bonds to form a two-dimensional planar network structure. Graphdiyne has a uniform pore structure and a large pi conjugated system, and has a wide application prospect in the fields of gas separation, catalysis, energy and the like. At the same time, graphdiyne is also a two-dimensional semiconductor material with a direct band gap (0.44-1.47 eV) and a high room-temperature carrier mobility (10 4 -10 5 cm 2 ·V -1 ·s -1 ) and has been widely concerned in the fields of electronics, optics and magnetism.

[0003] However, due to the instability of the monomer, the free rotation of the carbon-carbon single bond and the side reaction, etc., the synthesis of graphdiyne in experiments has great challenges. In 2010, Professor Li Yuliang's team of the Chinese Academy of Sciences first synthesized graphdiyne in experiments, and since then, scientists have developed many preparation methods of graphdiyne powder. Such as "interface limited method", "van der Waals epitaxy method", "explosion method" and the like, which promote the development of the field of graphdiyne synthesis.

[0004] However, the above methods have the disadvantages of complex operation, and the obtained graphdiyne powder material has a small flake diameter, which limits its further application. Therefore, developing a fast and simple preparation method of large flake diameter graphdiyne powder is conducive to further exploring the properties of graphdiyne and tapping the application potential of graphdiyne. SUMMARY

[0005] In order to overcome the above technical problems, the present application provides a preparation method of a large flake diameter graphdiyne powder material with a two-dimensional nanosheet structure, which specifically comprises the following steps:

[0006] S1, dissolving a catalyst in a solvent to obtain a catalyst solution;

[0007] S2, mixing a monomer with the catalyst solution and placing it into a microwave reactor to perform microwave reaction, thereby obtaining the graphdiyne powder material.

[0008] The technical scheme of the present application does not need to use a substrate. The present application prepares a large-particle (5-10 μm) graphite diacetylene powder material with a two-dimensional nanosheet structure under the condition of no substrate by using microwave reaction.

[0009] The solvent of the catalyst solution is an organic solvent; preferably one or more of tetrahydrofuran, chlorobenzene, dimethyl sulfoxide, pyridine, and N,N-dimethylformamide; more preferably a mixed solvent of dimethyl sulfoxide and pyridine.

[0010] According to one specific embodiment of the present application, the monomer is hexaethynylbenzene (HEB).

[0011] According to one specific embodiment of the present application, the preparation method of the monomer hexaethynylbenzene (HEB) is as follows: hexa(trimethylsilylethynyl)benzene (HEB-TMS) is dissolved in a solvent, which is preferably tetrahydrofuran, stirring under inert gas protection, adding tetra-n-butylammonium fluoride (TBAF), reaction in an ice-salt bath, avoiding light, washing and rotary evaporation of the obtained product to obtain the monomer hexaethynylbenzene.

[0012] According to one specific embodiment of the present application, the catalyst is a copper catalyst; preferably one or more of copper sulfate, copper nitrate, and copper acetate.

[0013] According to one specific embodiment of the present application, the concentration of the catalyst is 0.01-10 mg / mL.

[0014] According to one specific embodiment of the present application, the power of the microwave is 100-2000 W.

[0015] According to one specific embodiment of the present application, the reaction time is 1-30 min.

[0016] According to one specific embodiment of the present application, the reaction temperature is 40-200℃.

[0017] According to one specific embodiment of the present application, it further comprises the following steps: after the reaction is completed, standing to room temperature, removing the solvent by centrifugation, and freeze-drying.

[0018] Beneficial effects:

[0019] The application adopts a substrate-free system combined with a microwave reaction to prepare a graphite diacetylene powder material with a two-dimensional nanosheet structure and a large sheet diameter (5-10 mu m). Unlike the graphite diacetylene film material prepared in the prior art, the graphite diacetylene powder material has a wider application in ion batteries, electrocatalysis, DNA detection, etc. The graphite diacetylene powder material prepared by the application has a two-dimensional nanosheet structure, fewer defects, higher crystallinity and mobility, and a larger specific surface area, and the surface can be regulated or modified to obtain a high-performance multifunctional material. In addition, the graphite diacetylene powder material prepared by the application has a large sheet diameter, which can reach 5-10 mu m. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A physical map of the graphite diacetylene powder dispersion liquid prepared in Example 1;

[0021] Figure 2 A physical map of the graphite diacetylene powder material prepared in Example 1;

[0022] Figure 3 A transmission electron microscope image of the graphite diacetylene powder material prepared in Example 1;

[0023] Figure 4 An atomic force microscope image of the graphite diacetylene powder material prepared in Example 1;

[0024] Figure 5 A Raman spectrum of the graphite diacetylene powder material prepared in Example 1;

[0025] Figure 6 A photoelectron spectroscopy (XPS) full spectrum and a C1s high-resolution spectrum of the graphite diacetylene powder material prepared in Example 1;

[0026] Figure 7 A synthesis schematic diagram of the graphite diacetylene powder material prepared in Example 1;

[0027] Figure 8 The a) diagram in the figure is a synthesis schematic diagram of the graphite diacetylene powder material prepared in Comparative Example 1;

[0028] Figure 8 The b) diagram in the figure is a scanning electron microscope image of NaCl@GDY of the graphite diacetylene powder material prepared in Comparative Example 1;

[0029] Figure 8 The c) diagram in the figure is a scanning electron microscope image of a GDY film on a SiO2 / Si substrate of the graphite diacetylene powder material prepared in Comparative Example 1;

[0030] Figure 8 The d) diagram in the figure is an AFM image of the graphite diacetylene powder material prepared in Comparative Example 1;

[0031] Figure 9 Figure a) is a hot stage heating preparation GDY device diagram of Comparative Example 2;

[0032] Figure 9 Figure b) is a Raman diagram of the GDY powder obtained in Comparative Example 2;

[0033] Figure 9 Figure c) is a SEM diagram of the GDY powder obtained in Comparative Example 2;

[0034] Figure 10 Figure a) is a sample diagram after reaction of Comparative Example 3 using copper foil as the substrate and hot stage heating;

[0035] Figure 10 Figure b) is a Raman diagram of the GDY powder on the copper foil obtained in Comparative Example 3;

[0036] Figure 10 Figure c) is a SEM diagram of the GDY powder on the copper foil obtained in Comparative Example 3. DETAILED DESCRIPTION

[0037] Typical embodiments embodying the features and advantages of the present application will now be described in detail. It should be understood that the application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, which are presented by way of example only, and that the description and drawings are to be regarded as illustrative in nature and not as restrictive.

[0038] The preparation process includes the following key process steps:

[0039] (1) The appropriate amount of catalyst and solvent are weighed according to the ratio and mixed in a clean beaker to obtain a mixed solution, and then the monomer used to synthesize the graphite diradical is mixed with the above-mentioned catalyst solution;

[0040] (2) The beaker containing the mixed solution of the monomer and the catalyst is placed in a microwave reactor, a magnetic stirrer is added to the beaker to stir, and a temperature probe is placed in the beaker to monitor the temperature;

[0041] (3) A constant power is set to heat the reaction solution, and the reaction starts under the action of the microwave;

[0042] (4) The constant power is controlled and the temperature is controlled during the reaction to obtain a dispersion liquid containing black graphite diradical powder;

[0043] (5) The graphite diradical powder dispersion liquid obtained by reaction is treated by washing, freeze-drying, etc. to obtain graphite diradical powder.

[0044] In step (1), the monomer required to synthesize the graphite diradical is subjected to deprotection treatment;

[0045] The deprotection process is a process of removing the trimethylsilyl protecting group from HEB-TMS to prepare HEB.

[0046] In step (1), the catalyst is copper catalyst, which can be any one of copper sulfate, copper nitrate and copper acetate;

[0047] In step (1), the concentration of the catalyst is 0.01-10 mg / mL;

[0048] In step (1), the solvent is organic solvent, which can be one or mixture of tetrahydrofuran, chlorobenzene, dimethyl sulfoxide, pyridine and N,N-dimethylformamide;

[0049] In step (1), the dispersion device is ultrasonic machine;

[0050] In step (3), the power of the microwave reactor is 100-2000 W;

[0051] In step (3), the reaction time is 1-30 min;

[0052] In step (4), the reaction temperature is 40-200℃;

[0053] In step (5), the washing process includes washing of the catalyst and the reaction solvent.

[0054] The preparation of the graphite diradical powder material of the embodiment of the present application will be further described below in combination with the drawings and specific examples.

[0055] The test methods involved in the examples are as follows: Raman characterization is performed by using a Raman spectrometer of LabRAM HR Evolution produced by Japan Horiba Company; transmission electron microscopy is performed by using FEI Tecnai F20; X-ray photoelectron spectroscopy (XPS) is performed by using Kratos Analytical Axis-Ultra spectrometer.

[0056] Example 1

[0057] Take 100 mL dimethyl sulfoxide (DMSO) and 20 mL pyridine (Py) solution mixed as solvent, 120 mg copper acetate solid dispersed in the above mixed solution, ultrasonic 30 min as catalyst solution for standby; Take 100 mg hexakis (trimethylsilylethynyl) benzene (HEB-TMS) solid dissolved in 100 mL tetrahydrofuran, under argon protection, stirring 10 minutes, 2 mL tetra-n-butylammonium fluoride (TBAF, 1M tetrahydrofuran solution) was added, in ice-salt bath, stirring reaction 15 minutes (avoid light), the product was separated with ethyl acetate and saturated brine, the organic phase was collected, HEB monomer solution was obtained, the solvent was removed by rotary evaporation, and used for the synthesis of graphite diacetylene powder.

[0058] The HEB monomer obtained by rotary evaporation was mixed with the catalyst solution, a magnetic stirrer was added to the beaker containing the reaction solution, and the temperature probe was immersed below the solution in the microwave reactor.

[0059] The microwave reactor was started, the constant power mode was selected, the reaction power was set to 200 W, the stirring was started, and the heating was started. When the temperature reached about 65℃, black precipitate was observed. After 2-3 min, the temperature reached 80-90℃, the reaction was stopped, and the graphite diacetylene powder dispersion solution was obtained.

[0060] After the reaction was completed, the dispersion solution was allowed to cool to room temperature, and the dispersion solution was evenly transferred to 50 mL centrifuge tubes. The DMSO / Py solvent was removed by centrifugation at 8000 r.m.p for 10 min. The supernatant was poured out, and an appropriate amount of pyridine solvent was added to each centrifuge tube. After ultrasonic dispersion, centrifugation was performed, and the washing solvent was repeated several times. The graphite diacetylene powder can also be evenly dispersed in pyridine solution overnight and then treated by centrifugation.

[0061] After removing the residual catalyst and solvent by centrifugation several times, a small amount of deionized water was added, and the graphite diacetylene powder dispersion solution was collected. The graphite diacetylene powder was frozen for a short time using liquid nitrogen, and then dried using a freeze dryer for 3 days to dryness. The graphite diacetylene powder sample was obtained.

[0062] Figure 1 The actual picture of the graphite diacetylene powder dispersion solution prepared in Example 1 is shown in the figure;

[0063] Figure 2 The actual picture of the graphite diacetylene powder material prepared in Example 1 is shown in the figure; Figure 2 It can be seen that it is a powder material, not a thin film structure.

[0064] Figure 3 The transmission electron microscopy (TEM) image of the graphite diacetylene powder material prepared in Example 1 is shown in the figure. It can be seen from the TEM image that the graphite diacetylene powder obtained under this condition has a large flake diameter, about 5-10 μm.

[0065] Figure 4 The image shown is an atomic force microscope image of the graphitic diacetylene powder material prepared in Example 1. It can be seen that the prepared graphitic diacetylene powder material has a two-dimensional sheet structure with a thickness of 8.62 nm.

[0066] Figure 5 The image shows the Raman spectrum of the graphitic diacetylene powder material prepared in Example 1. The characteristic peaks of the Raman spectrum originate from the stretching vibrations of the carbon-carbon single bonds connecting the carbon-carbon triple bond and the benzene ring. 1428 cm⁻¹ -1 1565cm -1 The spectral peak at 2174 cm⁻¹ originates from the stretching vibration of the carbon-carbon bonds in the benzene ring. -1 The characteristic spectral peaks at the location originate from the stretching vibrations of the diyne bond (-C≡CC≡C-), proving the formation of graphitic diyne.

[0067] Figure 6 The images show the full XPS spectrum and high-resolution C1s spectrum of the graphitic diacetylene powder material prepared in Example 1. The C1s peak can be deconvolved into four subpeaks, corresponding to C1s(sp) peaks. 2 ), CC(sp), CO, and C=O. Since the structure of graphitic diyne consists of benzene rings connected by diyne bonds (-C≡CC≡C-), therefore sp and sp 2 The peak area ratio of the hybrid carbon atoms is 2. A small amount of C=O may originate from impurities introduced during the reaction or defects generated during the reaction.

[0068] Figure 7 This is a schematic diagram of a method for synthesizing graphitic diyne powder materials. Under microwave assistance and the action of a catalyst, monomers are spliced ​​together to form large-diameter graphitic diyne structures.

[0069] Example 2

[0070] Except for the first stage microwave reactor power being 100W, the other conditions were the same as in Example 1.

[0071] Example 3

[0072] Except for the first stage microwave reactor power being 300W, the other conditions were the same as in Example 1.

[0073] Example 4

[0074] Except for the first stage microwave reactor power being 500W, the other conditions were the same as in Example 1.

[0075] Examples 2-4 all prepared graphitic diacetylene powder materials with large-diameter two-dimensional nanosheet structures.

[0076] Comparative Example 1

[0077] The subject group of Mr. Yin Chen et al. once used the solid / liquid interface microwave-induced temperature gradient method, with sodium chloride as the substrate, under microwave irradiation, the coupling reaction only occurred on the surface of sodium chloride, while the HEB monomer in the bulk solution remained stable and could completely diffuse to the solid / liquid interface, and finally obtained a few-layer GDY film with an average thickness of less than 2 nm, the macroscopic morphology was not powder, but also not a two-dimensional nanosheet structure, as shown in Figure 8 .

[0078] Comparative Example 2

[0079] This scheme does not use a substrate, but uses a conventional heating method

[0080] After the deprotection operation, the HEB monomer and the catalyst solution were fully mixed, and the conventional hot stage heating method was used to heat at 80°C to produce black GDY powder, which was further characterized as shown in the following figure, and it can be seen that the grown GDY powder is a three-dimensional thick structure, as shown in Figure 9 .

[0081] Comparative Example 3

[0082] After the deprotection operation, the HEB monomer and the solvent were fully mixed, a small piece of copper foil was added and used as the growth substrate, and the conventional hot stage heating method was used to heat at 80°C to produce black GDY powder, which was further characterized as shown in the following figure, which is a three-dimensional powder structure.

[0083] By analyzing the technical scheme of using microwave method and using substrate of Example 1 and Comparative Example 1, the technical scheme of not using substrate and not using microwave method of Comparative Example 2, and the technical scheme of not using microwave method and using substrate of Comparative Example 3, it can be known that the present application uses microwave method combined with no substrate system combined with microwave reaction, and a large piece of graphite double acetylene powder material with two-dimensional nanosheet structure is prepared.

Claims

1. A method of preparing a graphdiyne powder material, characterized in that, Specifically comprising the following steps: S1, dissolving a catalyst in a solvent to obtain a catalyst solution; S2, mixing a monomer with the catalyst solution, putting into a microwave reactor, and performing microwave reaction to obtain the graphdiyne powder material; The monomer is hexaethynylbenzene. The catalyst is a copper catalyst.

2. The production method according to claim 1, characterized by, The catalyst is one or more of copper sulfate, copper nitrate, and copper acetate.

3. The preparation method according to claim 1, characterized in that, The solvent is an organic solvent.

4. The production method according to claim 3, characterized by, The solvent is one or more of tetrahydrofuran, chlorobenzene, dimethyl sulfoxide, pyridine, and N,N-dimethylformamide.

5. The preparation method according to claim 1, characterized in that, The power of the microwave is 100-2000 W.

6. The production method according to claim 5, wherein The power of the microwave is 100-500 W.

7. The preparation method according to claim 1, characterized in that, The reaction time is 1-30 min.

8. The method of claim 1, wherein, The reaction temperature is 40-200 DEG C.

9. The method of claim 1, wherein, Further comprising the following steps: after the reaction, standing to room temperature, removing the solvent by centrifugation, and freeze-drying.

10. The method of claim 1, wherein, The preparation method of the monomer hexaethynylbenzene is as follows: dissolving hexa(trimethylsilylethynyl)benzene in a solvent, stirring under inert gas protection, adding tetra-n-butylammonium fluoride, reacting in an ice-salt bath, avoiding light, washing and rotary evaporation of the obtained product to obtain the monomer hexaethynylbenzene.

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