Preparation method of composite wave-absorbing material and composite wave-absorbing material
By preparing a composite material of Ti3C2Tx and polydopamine-modified silica microspheres, a composite microwave absorbing material with a specific microstructure was constructed, which solved the impedance mismatch problem of Ti3C2Tx and achieved efficient absorption of electromagnetic waves.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-07
- Publication Date
- 2026-03-17
AI Technical Summary
Ti3C2Tx materials suffer from poor impedance matching characteristics due to their high carrier mobility. Electromagnetic waves are more likely to be reflected rather than absorbed into the material, which limits their practical application in the field of microwave absorption.
By mixing Ti3C2Tx powder with polydopamine-modified silica microspheres and subjecting them to high-temperature carbonization and silica etching, a composite microwave absorbing material with a specific microstructure is constructed. This material combines the strong conductivity of Ti3C2Tx, the dipole polarization loss of nitrogen-doped carbon, and the interfacial polarization and multiple scattering of the hollow structure to achieve efficient dissipation of electromagnetic waves.
It alleviates the impedance mismatch problem caused by the high conductivity of Ti3C2Tx, increases the specific surface area and active sites, improves the absorption performance of electromagnetic waves, and achieves efficient absorption of electromagnetic waves.
Smart Images
Figure CN121674026A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of electromagnetic wave absorption technology, and in particular to a method for preparing a composite absorbing material and the composite absorbing material itself. Background Technology
[0002] With the rapid development of science and technology, 5G electronic devices have greatly facilitated people's daily lives. However, the widespread use of electronic devices has also inevitably brought about electromagnetic pollution, posing a potential risk to human health and the safety of precision instruments. To address this challenge, researchers have been dedicated to developing novel electromagnetic wave absorbing materials, including magnetic materials, two-dimensional transition metal carbides, and carbon-based materials. Ideally, electromagnetic wave absorbing materials should be able to effectively convert electromagnetic wave energy into heat or other forms of energy through dielectric loss, magnetic loss, or other loss mechanisms.
[0003] Two-dimensional material Ti3C2T x MXene has attracted much attention due to its high electrical conductivity, unique layered structure, abundant intrinsic defects, and tunable surface functional groups; however, Ti3C2T x Its high carrier mobility results in poor impedance matching characteristics, and electromagnetic waves are more likely to be reflected on its surface rather than absorbed inside the material, which limits its practical application in the field of microwave absorption. Summary of the Invention
[0004] This application aims to provide a method for preparing composite absorbing materials and the composite absorbing materials themselves, with the goal of improving the absorbing performance of the composite absorbing materials.
[0005] Firstly, this application proposes a method for preparing a composite microwave absorbing material, including providing Ti3C2T x Powder and polydopamine-modified silica microspheres, in which Ti3C2T x The powder and the polydopamine-modified silica microspheres are mixed and stirred in a solvent, then allowed to settle to obtain a first precipitate. The first precipitate is washed and dried to obtain a first powder. Under an inert gas environment, the first powder is subjected to high-temperature carbonization to obtain a first carbide. A silica etching solution is provided, and the first carbide is added to the silica etching solution to obtain a second carbide with the silica component removed. The second carbide is washed and dried to obtain a composite microwave absorbing material.
[0006] In some embodiments, the provision of Ti3C2T x The powder comprises: adding the Ti3AlC2 powder to hydrofluoric acid for reaction, centrifuging after the reaction is complete to obtain a second precipitate; washing the second precipitate until neutral, and drying to obtain the Ti3C2T. xpowder.
[0007] In some embodiments, the mass ratio of the Ti3AlC2 powder to the volume ratio of the hydrofluoric acid is (2~5) g:(50~100) ml.
[0008] In some embodiments, the preparation of the polydopamine-modified silica microspheres includes: mixing and stirring an ammonia solution, ethanol, and water to obtain a first mixture; adding tetraethyl orthosilicate to the first mixture to obtain a silica microsphere dispersion; adding a dopamine hydrochloride solution to the silica microsphere dispersion to obtain dopamine-loaded silica spheres; washing the dopamine-loaded silica spheres and drying them for 10 to 14 hours to obtain the polydopamine-modified silica microspheres.
[0009] In some embodiments, the volume ratio of the ammonia solution, ethanol, and water is 1:(24~30):(80~100).
[0010] In some embodiments, the concentration of the dopamine hydrochloride solution is 40 g / L to 60 g / L. The volume ratio of the dopamine hydrochloride solution to the silica microsphere dispersion is (4~6):53.
[0011] In some embodiments, the Ti3C2T x The mass ratio of the powder to the polydopamine-modified silica microspheres is (1~2):1.
[0012] In some embodiments, the high-temperature carbonization treatment of the first powder in an inert gas environment includes: placing the first powder in a tube furnace and heating it in the inert gas environment at a heating rate of 3°C / min to 8°C / min, raising the temperature to 800°C to 850°C, and heating for 1.5 hours to 3 hours. The inert gas includes at least one of helium, argon, and nitrogen.
[0013] In some embodiments, the concentration of the silica etching solution is 10 wt% to 15 wt%.
[0014] Secondly, embodiments of this application also provide a composite absorbing material, which is prepared using the method for preparing composite absorbing materials as described in any one of the first aspects.
[0015] Unlike existing technologies, this application provides a method for preparing a composite microwave absorbing material, the method comprising providing Ti3C2T x Powder and polydopamine-modified silica microspheres, Ti3C2T xPowder and polydopamine-modified silica microspheres are mixed and stirred in a solvent, then allowed to settle to obtain a first precipitate. The first precipitate is washed and dried to obtain a first powder. The first powder is then subjected to high-temperature carbonization in an inert gas environment to obtain a first carbide. A silica etching solution is provided, and the first carbide is added to the silica etching solution to obtain a second carbide with the silica component removed. The second carbide is washed and dried to obtain a composite microwave absorbing material. This method involves using Ti3C2T… x A composite microwave absorbing material with a specific microstructure was constructed by combining polydopamine-modified silica microspheres with Ti3C2T through carbonization and etching processes. This composite microwave absorbing material exhibits a synergistic effect of multiple loss mechanisms and incorporates Ti3C2T x The high conductivity of Ti3C2T, the dipole polarization loss of nitrogen-doped carbon, and the interfacial polarization and multiple scattering brought about by the hollow structure enable efficient dissipation of electromagnetic waves. The nitrogen-doped hollow carbon structure effectively mitigates the degradation of Ti3C2T. x The impedance mismatch caused by high conductivity allows more electromagnetic waves to enter the interior of the absorbing material without being reflected. Furthermore, hollow carbon microspheres are attached to Ti3C2T... x On the lamellae, the amount of Ti3C2T can be reduced. x The stacking of layers increases the specific surface area and active sites of the composite absorbing material, thereby improving its absorption performance.
[0016] Additional aspects and advantages of the embodiments of this application will be described, shown, or illustrated in part by way of implementation of the embodiments of this application in the following description. Attached Figure Description
[0017] One or more embodiments are illustrated by way of example with reference to the accompanying drawings, which are not intended to limit the embodiments, and elements having the same reference numerals in the drawings are designated as similar elements.
[0018] Figure 1 Flowcharts illustrating some methods for preparing composite microwave absorbing materials provided in the embodiments of this application; Figure 2 This is a schematic diagram of the structure of the composite absorbing material provided in the embodiments of this application; Figure 3 This is a schematic cross-sectional view of the hollow carbon microspheres provided in an embodiment of this application. Detailed Implementation
[0019] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.
[0020] In this application, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that is mutually exclusive with other embodiments.
[0021] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0022] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.
[0023] The technical features involved in the different embodiments of this application described below can be combined with each other as long as they do not conflict with each other.
[0024] Firstly, this application proposes a method for preparing a composite microwave absorbing material, please refer to... Figure 1 The preparation method includes the following steps: Step S1: Provide Ti3C2T x Powder and polydopamine-modified silica microspheres, Ti3C2T x The powder and polydopamine-modified silica microspheres were mixed and stirred in a solvent and then allowed to settle to obtain the first precipitate.
[0025] Ti3C2T x MXene is a two-dimensional layered transition metal carbide with unique electrical, optical, and mechanical properties, including high electrical conductivity and a large specific surface area. In this designation, "Ti" represents titanium, "C" represents carbon, and "T" represents titanium. x "" indicates functional groups on the surface of the material, which are typically -OH (hydroxyl), -F (fluorine), or -O (oxygen), etc. As an electromagnetic wave absorbing material, Ti3C2T x Electromagnetic waves can be attenuated through methods such as conductive loss, multiple reflections, or polarization loss.
[0026] In some embodiments, Ti3C2T is provided xThe powder consists of: Ti3AlC2 powder added to hydrofluoric acid for reaction; after the reaction is complete, centrifugation is performed to obtain a second precipitate. The second precipitate is washed until neutral and dried to obtain Ti3C2T. x Powder. The mass ratio of Ti3AlC2 powder to hydrofluoric acid is (2~5) g:(50~100) ml. Any value within (2~5) g:(50~100) ml can be selected, for example, 2:100, 2:80, 2:60, 2:50, 3:100, 3:90, 3:80, 4:100, or 5:100.
[0027] Polydopamine (PDA) is a biomimetic polymer with advantages such as strong adhesion and ease of preparation and modification. PDA-modified silica microspheres (PDA@SiO2 microspheres) are microspheres formed by encapsulating silica with PDA. The PDA on the surface of the PDA-modified silica microspheres exhibits extremely strong adhesion, enabling the Ti3C2T... x During the mixing process of powder and PDA@SiO2 microspheres, the PDA@SiO2 microspheres can be firmly adsorbed onto Ti3C2T x The surface of the nanosheets. Polydopamine contains abundant carbon and nitrogen elements, which will carbonize into a nitrogen-doped carbon layer during subsequent heat treatment.
[0028] In some embodiments, the preparation of polydopamine-modified silica microspheres includes: mixing and stirring an ammonia solution, ethanol, and water to obtain a first mixture; adding tetraethyl orthosilicate to the first mixture to obtain a silica microsphere dispersion; adding a dopamine hydrochloride solution to the silica microsphere dispersion to obtain dopamine-loaded silica spheres; washing the dopamine-loaded silica spheres and drying them for 10 to 14 hours to obtain polydopamine-modified silica microspheres.
[0029] Step S2: The first precipitate is washed and dried to obtain the first powder. The first precipitate is Ti3C2T. x / PDA@SiO2 powder.
[0030] In some embodiments, washing and drying the first precipitate includes: washing the first precipitate with deionized water at least three times, and then drying the first precipitate in a vacuum oven at a temperature of 70°C to 90°C for 18 to 36 hours.
[0031] Step S3: Under an inert gas environment, the first powder is subjected to high-temperature carbonization treatment by a high-temperature carbonization method to obtain the first carbide.
[0032] High-temperature carbonization is a heating technology that involves heating carbon-containing raw materials under specific temperature and atmosphere control to remove non-carbon elements from the raw materials in gaseous form, ultimately forming a solid product with carbon as the main component.
[0033] During the high-temperature carbonization process, polydopamine is pyrolyzed and transformed into a nitrogen-doped carbon layer structure. This carbon layer structure can provide conductive loss, and the nitrogen atoms can also introduce enhanced polarization loss. The carbonization process also allows the carbon layer to bond with Ti3C2T. x The connections between the layers are more robust.
[0034] In some embodiments, the first powder is subjected to high-temperature carbonization treatment in an inert gas environment by a high-temperature carbonization method, including placing the first powder in a tube furnace and heating it in an inert gas environment at a heating rate of 3 °C / min to 8 °C / min, heating it to 800 °C to 850 °C, and heating it for 1.5 h to 3 h. The inert gas includes at least one of helium, argon, and nitrogen.
[0035] Step S4: Provide a silicon dioxide etching solution, add the first carbide to the silicon dioxide etching solution, and obtain a second carbide with the silicon dioxide component removed.
[0036] Silica etching solutions are etching solutions designed to remove silica. For example, hydrofluoric acid aqueous solutions. Silica etching solutions can selectively dissolve and remove silica from the first carbide, causing PDA@SiO2 microspheres to form nitrogen-doped hollow carbon microspheres. These hollow carbon microspheres then bond to Ti3C2T. x The nitrogen-doped hollow carbon microspheres on the surface of the sheets make the composite absorbing material lightweight, and the hollow structure reduces the overall dielectric constant of the composite absorbing material, alleviating the problems associated with Ti3C2T. x The impedance mismatch caused by high conductivity allows more electromagnetic waves to enter the interior of the absorbing material without being reflected. Furthermore, the electromagnetic waves penetrate the carbon layer and reach Ti3C2T. x When the electromagnetic waves are layered, they are reflected back into the cavity. The cavity interface can also reflect and scatter the incident electromagnetic waves multiple times, resulting in secondary absorption and loss, which prolongs the propagation path of the electromagnetic waves and increases the probability of loss.
[0037] Step S5: Wash and dry the second carbide to obtain the composite microwave absorbing material.
[0038] Among them, the composite absorbing material is Ti3C2T x / NHCS, NHCS (N-doped Hollow Carbon Spheres).
[0039] In some embodiments, washing and drying the second carbide includes: providing an aqueous ethanol solution to wash the second carbide at least three times to remove residual silicon dioxide etching solution and its byproducts, and placing the washed second carbide in a drying oven at a temperature of 50°C to 70°C for vacuum drying.
[0040] This application provides a method for preparing a composite microwave absorbing material, the method including providing Ti3C2T x Powder and polydopamine-modified silica microspheres, Ti3C2T x Powder and polydopamine-modified silica microspheres are mixed and stirred in a solvent, then allowed to settle to obtain a first precipitate. The first precipitate is washed and dried to obtain a first powder. The first powder is then subjected to high-temperature carbonization in an inert gas environment to obtain a first carbide. A silica etching solution is provided, and the first carbide is added to the silica etching solution to obtain a second carbide with the silica component removed. The second carbide is washed and dried to obtain a composite microwave absorbing material. This method involves using Ti3C2T… x A composite microwave absorbing material with a specific microstructure was constructed by combining polydopamine-modified silica microspheres with Ti3C2T through carbonization and etching processes. This composite microwave absorbing material exhibits a synergistic effect of multiple loss mechanisms and incorporates Ti3C2T x The high conductivity of Ti3C2T, the dipole polarization loss of nitrogen-doped carbon, and the interfacial polarization and multiple scattering brought about by the hollow structure enable efficient dissipation of electromagnetic waves. The nitrogen-doped hollow carbon structure alleviates the high conductivity of Ti3C2T. x The impedance mismatch caused by high conductivity allows more electromagnetic waves to enter the interior of the absorbing material without being reflected. Furthermore, hollow carbon microspheres are attached to Ti3C2T... x On the lamellae, the amount of Ti3C2T can be reduced. x The stacking of layers increases the specific surface area and active sites of the composite absorbing material, thereby improving its absorption performance.
[0041] In some embodiments, the volume ratio of ammonia solution, ethanol, and water is 1:(24~30):(80~100). Within this volume ratio range, the ammonia solution provides a suitable alkaline environment for the reaction system, promoting the hydrolysis and condensation reaction of tetraethyl orthosilicate, while ethanol plays a role in regulating the polarity and dispersibility of the reaction system. Water serves as the reaction medium, and the synergistic effect of the three components can control the particle size and dispersion uniformity of silica microspheres.
[0042] In some embodiments, the concentration of the dopamine hydrochloride solution is 40 g / L to 60 g / L. Any value within the range of 40 g / L to 60 g / L, or any range between two values, can be selected, such as any value of 40 g / L, 45 g / L, 50 g / L, 55 g / L, or 60 g / L, or any range between 40 g / L to 60 g / L and 45 g / L to 55 g / L. The volume ratio of the dopamine hydrochloride solution to the silica microsphere dispersion is (4~6):53. Within this concentration range, it is beneficial for dopamine hydrochloride to fully polymerize on the surface of the silica microspheres, forming a uniform polydopamine film layer of suitable thickness, which facilitates the effective formation of the nitrogen-doped carbon layer during subsequent carbonization. For example, when the concentration of the dopamine hydrochloride solution is 40 g / L to 60 g / L, it is beneficial for the formation of a uniform and complete polydopamine film layer on the silica surface.
[0043] In some embodiments, Ti3C2T x The mass ratio of powder to polydopamine-modified silica microspheres is (1~2):1 to ensure sufficient Ti3C2T. x The sheet-like structure allows PDA@SiO2 microspheres to adhere and reduces excessive Ti3C2T. x The stacking of layers affects the absorption performance of composite absorbing materials.
[0044] In some embodiments, the concentration of the silica etching solution is 10 wt% to 15 wt%. This concentration range can effectively dissolve silica while reducing the impact on nitrogen-doped carbon layers and Ti3C2T. x The layered structure causes excessive erosion, resulting in more complete and clean removal of silica, and the reaction is mild, reducing damage to the carbon layer caused by an overly rapid reaction.
[0045] Secondly, embodiments of this application also provide a composite absorbing material, which is prepared using the method for preparing composite absorbing materials as described in any embodiment of the first aspect.
[0046] Please refer to Figure 2 The composite absorbing material 100 includes Ti3C2T x The sheet 10 and hollow carbon microspheres 20, with multiple hollow carbon microspheres 20 attached to Ti3C2T x The two surfaces of layer 10. Then combined... Figure 3 The hollow carbon microspheres 20 include a hollow structure 21 and a nitrogen-doped carbon layer 22, with the nitrogen-doped carbon layer 22 enclosing the hollow structure 21. The nitrogen-doped carbon layer 22 is combined with Ti3C2T x The surfaces of the sheets 10 are tightly bonded to form a composite microwave absorbing material 100.
[0047] The preparation method of composite absorbing materials is described below with reference to specific embodiments: Example 1 (1) Take 5 mg of Ti3C2T x The powder and 5 mg of PDA@SiO2 powder were placed in 10 mL of deionized water and stirred thoroughly at 60 °C for 3 h to obtain a homogeneous solution. The solution was then allowed to settle at room temperature for 24 h. The first precipitate was collected and placed in a centrifuge tube, washed three times with deionized water, and then dried in a vacuum oven at 80 °C for 24 h to obtain the first powder. The first powder was heated in a tube furnace under argon protection at a heating rate of 5 °C / min to 800 °C, and heated for 2 h before natural cooling to obtain the first carbide. The first carbide was reacted in a 10 wt% HF solution for 24 h to obtain a second carbide with the silica component removed. The second carbide was washed three times with a 1:1 volume ratio of ethanol and pure water, and then dried in a vacuum oven at 60 °C for 12 h to obtain Ti3C2T. x Composite absorbing material of / NHCS.
[0048] Example 2 (1) 5 g of Ti3AlC2 powder was slowly added to 100 mL of hydrofluoric acid. After stirring continuously for 24 h at room temperature, the mixture was centrifuged at 3500 rpm to obtain a second precipitate. The second precipitate was washed several times with deionized water until the pH of the supernatant was 6.5. The second precipitate was then removed and vacuum dried for 24 h to obtain Ti3C2T. x powder.
[0049] (2) 1 mL of ammonia solution, 24 mL of ethanol, and 80 mL of ultrapure water were mixed and stirred for 30 min to obtain a first mixture. Then, 1 mL of tetraethyl orthosilicate was added to the first mixture, and the mixture was stirred continuously for 30 min to obtain a silica microsphere dispersion. Next, 12 mL of a 50 g / L dopamine hydrochloride solution was added dropwise to the silica microsphere dispersion, and stirring was continued for 36 h to obtain dopamine-loaded silica spheres. The dopamine-loaded silica spheres were washed three times with ultrapure water and then dried in a vacuum drying oven at 60 ℃ for 12 h to obtain PDA@SiO2 powder.
[0050] (3) Take 10 mg of Ti3C2T xThe powder and 5 mg of PDA@SiO2 powder were placed in 10 mL of deionized water and stirred thoroughly at 60 °C for 3 h to obtain a homogeneous solution. The solution was then allowed to settle at room temperature for 24 h. The first precipitate was collected and placed in a centrifuge tube, washed three times with deionized water, and then dried in a vacuum oven at 80 °C for 24 h to obtain the first powder. The first powder was heated in a tube furnace under argon protection at a heating rate of 5 °C / min to 850 °C, and heated for 2 h before natural cooling to obtain the first carbide. The first carbide was reacted in a 10 wt% HF solution for 24 h to obtain a second carbide with the silica component removed. The second carbide was washed three times with a 1:1 volume ratio of ethanol and pure water, and then dried in a vacuum oven at 60 °C for 12 h to obtain Ti3C2T. x Composite absorbing material of / NHCS.
[0051] Comparison document 1 (1) 5 g of Ti3AlC2 powder was slowly added to 100 mL of hydrofluoric acid. After stirring continuously for 24 h at room temperature, the mixture was centrifuged at 3500 rpm to obtain a second precipitate. The second precipitate was washed several times with deionized water until the pH of the supernatant was 6.5. The second precipitate was then removed and vacuum dried for 24 h to obtain Ti3C2T. x powder.
[0052] (2) 1 mL of ammonia solution, 24 mL of ethanol, and 80 mL of ultrapure water were mixed and stirred for 30 min to obtain a first mixture. Then, 1 mL of tetraethyl orthosilicate was added to the first mixture, and the mixture was stirred continuously for 30 min to obtain a silica microsphere dispersion. Next, 12 mL of a 50 g / L dopamine hydrochloride solution was added dropwise to the silica microsphere dispersion, and stirring was continued for 36 h to obtain dopamine-loaded silica spheres. The dopamine-loaded silica spheres were washed three times with ultrapure water and then dried in a vacuum drying oven at 60 ℃ for 12 h to obtain PDA@SiO2 powder.
[0053] (3) Take 10 mg of Ti3C2T xThe powder and 5 mg of PDA@SiO2 powder were placed in 10 mL of deionized water and stirred thoroughly at 60 °C for 3 h to obtain a homogeneous solution. The solution was then allowed to settle at room temperature for 24 h. The first precipitate was collected and placed in a centrifuge tube, washed three times with deionized water, and then dried in a vacuum oven at 80 °C for 24 h to obtain the first powder. The first powder was heated in a tube furnace under argon protection at a heating rate of 5 °C / min to 850 °C, and heated for 2 h before natural cooling to obtain the first carbide. The first carbide was washed three times with a 1:1 volume ratio of ethanol and pure water, and then dried in a vacuum oven at 60 °C for 12 h to obtain Ti3C2T. x Composite absorbing material of / NHCS.
[0054] The microwave absorption performance of the composite microwave absorbing materials prepared in Example 1, Example 2, and Comparative Example 1 was tested. The microwave absorption performance results of different examples and comparative examples are shown in Table 1.
[0055] Table 1
[0056] According to the absorption performance test results, comparing the above embodiments and comparative examples, the RLmin of the composite absorbing material in Example 1 with a thickness of only 1.75 mm is -48.75 dB, and the effective absorption band is 4.86 GHz. The RLmin of the composite absorbing material in Example 2 with a thickness of 2.05 mm is -47.56 dB, and the effective absorption band is 4.55 GHz. The RLmin of the composite absorbing material in Comparative Example 1 with a thickness of 2.50 mm is -19.82 dB, and the effective absorption band is 1.92 GHz. It can be seen that the composite absorbing materials in Examples 1 and 2 absorb electromagnetic waves more fully. The hollow carbon microspheres in the composite absorbing materials in these examples alleviate the absorption of Ti3C2T... x The impedance mismatch caused by high conductivity allows more electromagnetic waves to enter the interior of the absorbing material without being reflected. Furthermore, the interfacial polarization and multiple scattering brought about by the hollow structure achieve efficient dissipation of electromagnetic waves, enhancing the absorption performance of the composite absorbing material.
[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.
Claims
1. A method for preparing a composite wave-absorbing material, characterized in that, The method comprises the following steps: Provide Ti3C2T x Powder and polydopamine-modified silica microspheres, in which Ti3C2T x The powder and the polydopamine-modified silica microspheres were mixed and stirred in a solvent and then allowed to settle to obtain a first precipitate; washing and drying the first precipitate to obtain a first powder; carburizing the first powder under an inert gas environment to obtain a first carburide by a high-temperature carburizing method; providing a silicon dioxide etching solution, and adding the first carburide into the silicon dioxide etching solution to obtain a second carburide from which a silicon dioxide component is removed; washing and drying the second carburide to obtain a composite wave-absorbing material.
2. The production method according to claim 1, characterized by, The providing Ti3C2T x The powder comprises: adding the Ti3AlC2 powder into hydrofluoric acid to react, and performing centrifugal treatment after the reaction is completed to obtain a second precipitate; The second precipitate is washed to neutrality, and after drying the Ti3C2T x powder is obtained.
3. The preparation method according to claim 2, characterized in that, The mass of the Ti3AlC2 powder and the volume of the hydrofluoric acid are in a ratio of (2-5) g:(50-100) ml.
4. The method of claim 1, wherein, The preparation of the polydopamine-modified silica microspheres comprises the following steps: mixing and stirring an ammonia solution, ethanol and water to obtain a first mixed solution, and adding tetraethyl orthosilicate into the first mixed solution to obtain a silica microsphere dispersion liquid; adding a dopamine hydrochloride solution into the silica microsphere dispersion liquid to obtain a dopamine-loaded silica gel ball; washing and drying the dopamine-loaded silica gel ball for 10-14 hours to obtain the polydopamine-modified silica microspheres.
5. The preparation method according to claim 4, characterized in that, The volume ratio of the ammonia solution, ethanol and water is 1:(24-30):(80-100).
6. The preparation method according to claim 4, characterized in that, The concentration of the dopamine hydrochloride solution is 40-60 g / L; The volume ratio of the dopamine hydrochloride solution and the silica microsphere dispersion liquid is (4-6):
53.
7. The preparation method according to claim 1, characterized in that, The Ti3C2T x The mass ratio of the powder and the polydopamine modified silica microspheres is (1~2):
1.
8. The method of claim 1, wherein, The carburizing the first powder under an inert gas environment to obtain a first carburide by a high-temperature carburizing method comprises the following steps: placing the first powder in a tube furnace to heat under the inert gas environment, the heating rate is 3-8 ℃ / min, the temperature is raised to 800-850 ℃, and the heating time is 1.5-3 hours; The inert gas comprises at least one of helium, argon and nitrogen.
9. The method of claim 1, wherein, The concentration of the silicon dioxide etching solution is 10-15 wt%.
10. A composite wave-absorbing material, characterized in that, The composite wave-absorbing material is prepared by the method according to any one of claims 1-9.