A kind of wadding-like macroporous carbon material and its preparation method and application

Abstract

The present invention provides a reticular macroporous carbon material and a preparation method and application thereof, wherein 4,4'-diaminobiphenyl and 1,4-benzoquinone are heated and reacted in an alcohol solvent to prepare a reticular macroporous precursor, and then the precursor is prepared by high-temperature cracking and carbonization under the protection of an inert gas. The carbon material prepared by the present invention has a specific reticular macroporous morphology, rich pores, and pores that are connected and evenly distributed throughout the carbon material particles, and has surface properties doped with nitrogen and oxygen heteroatoms. The carbon material or the carbon material after further activation and modification can be applied to supercapacitor electrode materials, adsorption materials, filter filling materials, template materials, composite carrier materials, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon material preparation, and in particular to a fibrous macroporous carbon material and a preparation method and application thereof. Background Art

[0002] Carbon materials have stable chemical properties and excellent surface chemical properties, and are widely used in energy storage materials, adsorption materials, catalytic materials, template materials, molecular sieves and composite carriers. The microscopic morphology and surface chemical properties of carbon materials are crucial to the performance of carbon materials in specific applications.

[0003] There are two main methods for preparing carbon materials: hydrothermal carbonization and direct carbonization. The hydrothermal carbonization method mainly uses organic sugars or carbohydrates as carbon sources and water as reaction medium to produce carbon materials in a reactor at a certain temperature and pressure. The morphology of the carbon material prepared by the hydrothermal carbonization method is affected by the concentration of the reaction raw materials and the reaction conditions, and the product particle size is relatively small and uniform. The morphology of the carbon materials prepared by the hydrothermal carbonization method is mostly spherical, layered or granular, and the hydrothermal reaction usually involves high pressure conditions. The direct carbonization method is to heat the carbon source precursor to a high temperature in an inert gas environment for cracking. The cracking conditions are divided into slow cracking, medium cracking and fast cracking. The cracking conditions will also affect the morphology of the prepared carbon material. It has become a widely used method for preparing carbon materials. However, the morphology of the carbon material prepared by the direct carbonization method mainly depends on the morphology of the precursor. After direct carbonization cracking, the morphology of the precursor is retained in the carbon material, especially the macroporous structure. At present, the precursors of the direct carbonization method are mostly biomass, and the microstructure of the prepared carbon materials mostly show the structural characteristics of biomass, or soft / hard templates are used to synthesize precursors to prepare carbon materials with specific morphologies. The template method usually involves relatively expensive raw materials and the post-processing process is relatively complicated.

[0004] At present, there are many methods or precursors for preparing porous carbon materials with microscopic large pores into carbon materials with different morphologies and properties, but they still cannot meet the new needs of scientific and technological progress and social development. In particular, there are relatively few carbon particle materials with large network pores. Methods for preparing carbon materials with specific large network pore morphology with high reproducibility still need to be further developed. Summary of the invention

[0005] In order to make up for the shortcomings of the prior art, the present invention provides a flocculent macroporous carbon material. The flocculent macroporous carbon material is prepared by heating 4,4'-diaminobiphenyl and 1,4-benzoquinone in an alcohol solvent to obtain a flocculent macroporous precursor, which is then prepared by high-temperature pyrolysis and carbonization under the protection of an inert gas.

[0006] The present invention also provides a method for preparing the fibrous macroporous carbon material, comprising the following steps:

[0007] (1) Preparation of flocculent macroporous precursor:

[0008] 4,4'-diaminobiphenyl, 1,4-benzoquinone and FeCl3 are mixed in an alcohol solvent, and then ultrasonically dispersed and heated to reflux for reaction. After the reaction is completed and cooled, the mixture is filtered and the filter cake is dried to obtain a flocculent macroporous precursor.

[0009] (2) Carbonization of the flocculent macroporous precursor:

[0010] The floc-like macroporous precursor is subjected to high-temperature cracking and carbonization under the protection of an inert gas to prepare a floc-like macroporous carbon material.

[0011] Preferably, in step (1), the alcohol solvent is selected from one of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, cyclopentanol, and cyclohexanol, and the filtration detergent is selected from one or more of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and water.

[0012] Preferably, in step (1), the mass ratio of 4,4'-diaminobiphenyl, 1,4-benzoquinone and FeCl3 is 1:(1.17-2.35):(0-2.64).

[0013] Preferably, in step (1), the amount of alcohol solvent required per gram of 4,4'-diaminobiphenyl is 20 to 200 mL.

[0014] Preferably, in step (1), the heating reflux temperature is 65 to 150° C., and the heating reflux time is 4 to 24 hours.

[0015] Preferably, in step (2), the inert gas is selected from one of nitrogen, helium or argon.

[0016] Preferably, in step (2), the temperature of the high temperature cracking is 450 to 900° C., and the time of the high temperature cracking is 0.5 to 8 hours.

[0017] The present invention also provides applications of the flocculated macroporous carbon material or the flocculated macroporous carbon material prepared by the preparation method in the fields of supercapacitor electrode materials, adsorption materials, filtration filling materials, template materials and composite carrier materials.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The present invention provides a carbon material and a preparation method thereof. The prepared carbon material has a specific flocculent macroporous morphology, rich pores, and pores that are connected and evenly distributed throughout the carbon material particles, and has surface properties doped with nitrogen and oxygen atoms. The preparation method of the carbon material is simple, does not require the use of a template material, and is low in cost. The carbon material or the carbon material after further activation and modification can be applied to supercapacitor electrode materials, adsorption materials, filter filling materials, template materials, composite carrier materials, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention, in which:

[0021] Figure 1 This is a photo of the carbon material prepared in Example 1 of the present invention;

[0022] Figure 2 This is a scanning electron microscope image of the carbon material prepared in Example 1 of the present invention;

[0023] Figure 3 This is an X-ray diffraction pattern of the carbon material prepared in Example 1 of the present invention;

[0024] Figure 4 This is a Raman spectrum of the carbon material prepared in Example 1 of the present invention;

[0025] Figure 5 This is an X-ray photoelectron spectrum of the carbon material prepared in Example 1 of the present invention;

[0026] Figure 6 This is an isothermal adsorption-desorption curve diagram of the carbon material prepared in Example 1 of the present invention;

[0027] Figure 7 The carbon material prepared in Example 1 of the present invention is a scanning electron microscope image of an activated carbon material obtained by further mixing with KOH at a mass ratio of 1:3 and activating at 800° C. for 2 h under nitrogen protection;

[0028] Figure 8 The carbon material prepared in Example 1 of the present invention is further mixed with KOH at a mass ratio of 1:3 and then activated at 800° C. for 2 h under nitrogen protection to obtain an X-ray photoelectron spectrum of the activated carbon material;

[0029] Fig. 9 The carbon material prepared in Example 1 of the present invention is further mixed with KOH in a mass ratio of 1:3 and then activated at 800° C. for 2 h under nitrogen protection to obtain an isothermal adsorption-desorption curve of the activated carbon material. DETAILED DESCRIPTION

[0030] The disclosure below provides many different embodiments or examples to implement different structures of the present invention. In order to simplify the disclosure of the present invention, the parts and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, which itself does not indicate the relationship between the various embodiments and / or settings discussed.

[0031] Example 1

[0032] 0.28g of 4,4'-diaminobiphenyl, 0.51g of 1,4-benzoquinone and 0.54g of FeCl3 were mixed in 20mL of ethanol solvent, and after ultrasonic dispersion, the mixture was heated at 80°C for reflux reaction for 8h, and after the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with water for 3 times and dried to obtain a reticular macroporous precursor. The precursor was pyrolyzed and carbonized at 700°C for 3h under nitrogen protection to obtain the reticular macroporous carbon material provided by the present invention.

[0033] Figure 1 This is a photo of the carbon material prepared in this example, which appears as black powder particles in macroscopic form.

[0034] Figure 2 This is a scanning electron microscope image of the carbon material prepared in this example, which shows a flocculent network-like macroporous morphology, and the flocculent network-like pores are uniform and penetrate the entire carbon material particle.

[0035] Figure 3 This is the X-ray diffraction pattern of the carbon material prepared in this embodiment. The diffraction curve in the figure shows a broad peak as a whole, indicating that the carbon material of Example 1 of the present invention is in an amorphous state; the main diffraction peaks are at 2θ=24° and 2θ=43°, respectively, and the two broad peaks correspond to the (002) diffraction plane and (100) diffraction plane of amorphous carbon, respectively, indicating that the carbon material of the present invention has a graphite structure with good electrochemical properties.

[0036] Figure 4 This is the Raman spectrum of the carbon material prepared in this example. The two characteristic shifts in the figure are at 1335.3 cm -1 and 1587.2cm -1 The D peak and the G peak appear at the bottom.

[0037] Figure 5 This is the X-ray photoelectron spectrum of the carbon material prepared in this embodiment. The curve in the figure mainly shows three peaks at 284.5eV, 400.6eV and 532.2eV, which correspond to the characteristic peaks of C1s, N1s and O1s, respectively, indicating that the surface of the carbon material is mainly composed of three elements: C, N and O, wherein the atomic percentages of the three elements are 89.5%, 3.6% and 6.9%, respectively.

[0038] Figure 6 The isothermal adsorption-desorption curve of the carbon material prepared in this example has a specific surface area of ​​225.7 m 2 g -1 The curve conforms to the characteristics of type I / IV isotherms. At a relatively low relative pressure (P / P0<0.01), the nitrogen adsorption amount increases significantly with the increase of P / P0, indicating that the carbon material sample is rich in microporous structure; at a relatively high relative pressure (P / P0>0.4), an obvious H4-type hysteresis loop is presented, indicating that there is a mesoporous structure in the carbon material; as the relative pressure continues to increase, the nitrogen adsorption amount continues to increase significantly, indicating the existence of a macroporous structure.

[0039] The carbon material prepared in this example was further activated as follows: the carbon material was mixed with KOH in a mass ratio of 1:3 and ground, and then heated to 800°C under nitrogen protection for 2 hours for activation. The activated carbon material was treated with 1 mol L -1 The samples were washed with hydrochloric acid solution and deionized water and dried, and then characterized by scanning electron microscopy, X-ray photoelectron spectroscopy and isothermal adsorption-desorption.

[0040] Figure 7 This is the scanning electron microscope image of the carbon material prepared in this embodiment after the above-mentioned activation step. After the carbon material is etched and activated by KOH to form pores, the flocculent macroporous morphology of the carbon material can be completely retained, indicating that the microscopic pore structure of the carbon material is relatively stable and suitable for activation modification and other treatments.

[0041] Figure 8 The carbon material prepared in this embodiment has an X-ray photoelectron energy spectrum after the above activation step. The main peak positions of the curve still appear at 284.5 eV, 400.6 eV and 532.2 eV, indicating that after the carbon material is activated by KOH etching and pore formation, the element composition of the surface of the carbon material is still C, N, and O. The elements on the surface of the carbon material are relatively stable, and the atomic percentages of C, N, and O are 88.8%, 1.0%, and 10.2%, respectively.

[0042] Fig. 9The carbon material prepared in this embodiment is a graph of the isothermal adsorption-desorption curve after the above activation step. The curve still conforms to the characteristics of the type I / IV isotherm. At a relatively low relative pressure (P / P0<0.01), as the P / P0 increases, the nitrogen adsorption amount increases significantly, and the adsorption amount is much greater than that of the carbon material before activation, indicating that after the carbon material is activated by KOH etching and pore formation, the microporous structure increases significantly; at a relatively high relative pressure (P / P0>0.4), it still presents an obvious H4-type hysteresis loop, and then as the relative pressure continues to increase, the nitrogen adsorption amount continues to increase, indicating that the mesoporous structure and macroporous structure in the carbon material are well preserved; after the carbon material is activated by KOH etching and pore formation, the specific surface area of ​​the carbon material increases significantly, which is 2281.7 m 2 g -1 The increase in specific surface area is beneficial to the adsorption performance of carbon materials.

[0043] Example 2

[0044] 0.28g of 4,4'-diaminobiphenyl and 0.61g of 1,4-benzoquinone were mixed in 50mL of methanol solvent, and after ultrasonic dispersion, the mixture was heated under reflux at 70°C for 24h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with water for 3 times and dried to obtain a fibrous macroporous precursor. The precursor was pyrolyzed and carbonized at 900°C for 2h under nitrogen protection to obtain the fibrous macroporous carbon material of the present invention.

[0045] Example 3

[0046] 0.28g of 4,4'-diaminobiphenyl, 0.35g of 1,4-benzoquinone and 0.71g of FeCl3 were mixed in 10mL of 1-propanol solvent, and after ultrasonic dispersion, the mixture was heated under reflux at 100°C for 8h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with ethanol 10 times and dried to obtain a fibrous macroporous precursor. The precursor was pyrolyzed and carbonized at 800°C for 4h under the protection of helium to obtain the fibrous macroporous carbon material of the present invention.

[0047] Example 4

[0048] 0.28g of 4,4'-diaminobiphenyl, 0.41g of 1,4-benzoquinone and 0.26g of FeCl3 were mixed in 40mL of 2-propanol solvent, and after ultrasonic dispersion, the mixture was heated under reflux at 85°C for 10h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with methanol 3 times and then with water 3 times, and then dried to obtain a flocculent macroporous precursor. The precursor was pyrolyzed and carbonized at 800°C for 3h under argon protection to obtain the flocculent macroporous carbon material of the present invention.

[0049] Example 5

[0050] 0.28g of 4,4'-diaminobiphenyl, 0.52g of 1,4-benzoquinone and 0.33g of FeCl3 were mixed in 20mL of 1-butanol solvent, and after ultrasonic dispersion, the mixture was heated under reflux at 120°C for 6h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with 1-butanol for 3 times and dried to obtain a reticular macroporous precursor. The precursor was pyrolyzed and carbonized at 800°C for 2h under nitrogen protection to obtain the reticular macroporous carbon material of the present invention.

[0051] Example 6

[0052] 0.28g of 4,4'-diaminobiphenyl, 0.54g of 1,4-benzoquinone and 0.31g of FeCl3 were mixed in 20mL of 2-butanol solvent, and after ultrasonic dispersion, the mixture was heated under reflux at 100°C for 5h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with 2-butanol for 3 times and dried to obtain a reticular macroporous precursor. The precursor was pyrolyzed and carbonized at 800°C for 2h under nitrogen protection to obtain the reticular macroporous carbon material of the present invention.

[0053] Example 7

[0054] 0.28g of 4,4'-diaminobiphenyl and 0.58g of 1,4-benzoquinone were mixed in 50mL of ethanol solvent, and after ultrasonic dispersion, the mixture was heated at 80°C for reflux reaction for 18h. After the reaction was completed and cooled, the mixture was filtered, and the filter cake was washed with 1-propanol for 3 times and dried to obtain a fibrous macroporous precursor. The precursor was pyrolyzed and carbonized at 700°C for 3h under nitrogen protection to obtain the fibrous macroporous carbon material of the present invention.

[0055] Those skilled in the art will readily appreciate other embodiments of the invention after considering the specification and practicing the invention herein. The invention is intended to cover any variations, uses or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art of the invention. The specification and examples are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

[0056] It should be understood that the present invention is not limited to the exact construction that has been described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A fibrous macroporous carbon material, characterized in that: The flocculent macroporous carbon material is prepared by heating 4,4'-diaminobiphenyl and 1,4-benzoquinone in an alcohol solvent to obtain a flocculent macroporous precursor, and then undergoing high-temperature pyrolysis and carbonization under the protection of an inert gas. The preparation method of the flocculent macroporous carbon material comprises the following steps: (1) Preparation of flocculent macroporous precursor: Mixing 4,4'-diaminobiphenyl, 1,4-benzoquinone and FeCl3 in an alcohol solvent, performing ultrasonic dispersion and heating under reflux reaction, filtering after the reaction is completed and cooled, and drying the filter cake to obtain the flocculent macroporous precursor; (2) Carbonization of the flocculent macroporous precursor: The flocculent network macroporous precursor is subjected to high temperature cracking and carbonization under the protection of an inert gas, so as to prepare the flocculent network macroporous carbon material; In step (1), the heating reflux temperature is 65 to 150° C., and the heating reflux time is 4 to 24 hours; In step (2), the temperature of the high temperature cracking is 450-900°C, and the time of the high temperature cracking is 0.5-8h.

2. The fibrous macroporous carbon material according to claim 1, characterized in that: In step (1), the alcohol solvent is selected from one of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, 1-pentanol, cyclopentanol, and cyclohexanol, and the washing agent for filtration is selected from one or more of methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and water.

3. The fibrous macroporous carbon material according to claim 1, characterized in that: In step (1), the mass ratio of the 4,4'-diaminobiphenyl, the 1,4-benzoquinone and the FeCl3 is 1:(1.17-2.35):(0-2.64).

4. The fibrous macroporous carbon material according to claim 1, characterized in that: In step (1), the alcohol solvent required per gram of the 4,4'-diaminobiphenyl is 20 to 200 mL.

5. The fibrous macroporous carbon material according to claim 1, characterized in that: In step (2), the inert gas is selected from one of nitrogen, helium or argon.

6. Application of the fibrous macroporous carbon material according to any one of claims 1 to 5 in the fields of supercapacitor electrode materials, adsorption materials, filtration filling materials, template materials and composite carrier materials.

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