Multilayer broadband graphene / MXene wave-absorbing laminated structure constructed by electrostatic spinning technology and preparation method of multilayer broadband graphene / MXene wave-absorbing laminated structure

Abstract

The invention relates to a multilayer broadband graphene / MXene wave-absorbing laminated structure constructed by an electrostatic spinning technology and a preparation method of the multilayer broadband graphene / MXene wave-absorbing laminated structure, and belongs to the technical field of wave-absorbing material preparation. The preparation method of the graphene / MXene laminated structure wave-absorbing material comprises the following steps: respectively preparing a graphene nanofiber membrane and an MXene nanofiber membrane by adopting an electrostatic spinning method, carrying out drying treatment on the graphene nanofiber membrane and the MXene nanofiber membrane, measuring electromagnetic parameters of the graphene nanofiber membrane and the MXene nanofiber membrane, designing a laying sequence and a laying mode according to an impedance matching principle and an attenuation maximization principle, and preparing the graphene / MXene laminated structure wave-absorbing material. And after laying is completed, the multiple layers of fiber membranes are integrally immersed in the impregnation liquid, and after curing is completed, the final composite material is obtained. According to the multilayer broadband graphene / MXene wave-absorbing laminated structure, the advantages of high conductivity and the like of the graphene and the MXene are utilized, the graphene and the MXene are compounded with the high-molecular polymer to prepare the laminated wave-absorbing structure, the excellent wave-absorbing performance of the graphene and the MXene is fully played, and meanwhile, according to the impedance gradient design, the impedance matching characteristic can be improved, and the microwave absorbing capacity can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of preparing absorbing materials, and specifically relates to a multi-layer broadband graphene / MXene absorbing laminate structure constructed by electrostatic spinning technology and a preparation method thereof. Background Art

[0002] As a carbon material, graphene mainly attenuates electromagnetic waves through dielectric loss (mainly conduction loss and polarization loss). Due to its high specific surface area, high dielectric constant, and excellent thermal and electrical conductivity, it is widely used in the preparation of high-frequency electromagnetic wave absorbing materials. MXene is a type of two-dimensional inorganic compound with hydroxyl groups or terminal oxygen on the surface and the metallic conductivity of transition metal carbides. Its unique accordion-like layered microstructure makes it easy for electromagnetic waves to be reflected and scattered multiple times between its layers. However, the high conductivity of graphene and MXene itself also leads to a high dielectric constant, low magnetic permeability, poor attenuation loss, and does not meet the matching of characteristic impedance. Therefore, a single graphene material or MXene material cannot meet the requirements of lightweight and broadband absorbing materials, and the demand for the development of new broadband absorbing materials is growing. Summary of the invention

[0003] The purpose of the present invention is to provide a preparation method of a multi-layer broadband graphene / MXene absorbing laminate structure constructed by electrospinning technology. The prepared composite fabric absorbing material has the characteristics of lightness and flexibility, and meets the requirements of electromagnetic wave absorption.

[0004] The present invention also provides a multi-layer broadband graphene / MXene absorbing material prepared by the above-mentioned preparation method.

[0005] In order to achieve the above objectives, the technical solution adopted by the multi-layer broadband graphene / MXene absorbing laminate structure of the present invention is:

[0006] The preparation method of constructing a multi-layer broadband graphene / MXene absorbing laminate structure by electrospinning technology comprises the following steps: preparing graphene nanofiber membrane and MXene nanofiber membrane respectively by electrospinning, measuring their electromagnetic parameters after drying them, designing the stacking sequence and method according to the impedance matching principle and the attenuation maximization principle, immersing the multi-layer fiber membrane as a whole in the impregnation liquid after stacking, and obtaining the final composite material after curing.

[0007] Preferably, the preparation method of the graphene nanofiber membrane comprises the following steps: adding a certain mass fraction of defatted graphene powder to a mixed solution of polyacrylonitrile (PAN) and N,N-dimethylformamide (DMF), and magnetically stirring for more than 24 hours to obtain a graphene spinning precursor solution.

[0008] Preferably, the preparation method of the MXene nanofiber membrane comprises the following steps: fully dissolving polyvinyl pyrrolidone (PVP) in anhydrous ethanol, magnetically stirring until the solution is clear and transparent, then adding a certain mass of MXene powder, and magnetically stirring until it is fully dissolved.

[0009] Preferably, the electrospinning process parameters are as follows: the spinning solution is sucked into a 20 mL syringe, installed on a propulsion pump, connected to high voltage, the spinning machine voltage is set to 10-17 KV, the propulsion rate is 0.6-1.5 mL / h, the distance from the aluminum foil receiver is 8-20 cm, and electrospinning is performed at room temperature.

[0010] Preferably, the drying method of the nanofiber membrane includes vacuum drying method and natural air drying method.

[0011] Preferably, the impregnation liquid components include but are not limited to wave-transmitting materials such as cyanate ester and PU resin.

[0012] The technical solution adopted by the multi-layer broadband graphene / MXene absorbing laminate structure of the present invention is:

[0013] A multilayer broadband graphene / MXene wave absorbing laminated structure is prepared by the preparation method of constructing a multilayer broadband graphene / MXene wave absorbing laminated structure using the above-mentioned electrospinning technology.

[0014] The multi-layer broadband graphene / MXene absorbing laminated structure of the present invention utilizes the advantages of high conductivity, high dielectric constant, etc. of graphene and MXene, and composites them with high molecular polymers to prepare a laminated absorbing structure, giving full play to the high dielectric properties of graphene and MXene. At the same time, according to the impedance gradient design, the fiber membranes with different absorbing characteristics are arranged and laid in an orderly manner, which can improve the impedance matching characteristics and enhance the microwave absorption capacity. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a SEM image of graphene nanofibers used in Example 1 of the present invention;

[0016] Figure 2 This is a SEM image of MXene nanofibers used in Example 2 of the present invention; DETAILED DESCRIPTION

[0017] The technical solution of the present invention is further described below in conjunction with specific implementation methods.

[0018] Example 1

[0019] The method for preparing the multi-layer broadband graphene / MXene absorbing laminate structure of this embodiment comprises the following steps:

[0020] 1) A certain amount of polyacrylonitrile (PAN) powder is dissolved in N,N-dimethylformamide (DMF) solvent and magnetically stirred at room temperature for more than 8 hours. A certain mass fraction of defatted graphene powder is added to the polyacrylonitrile solution and magnetically stirred for more than 24 hours to obtain a graphene spinning precursor solution. In the solution, the mass fraction combinations of polyacrylonitrile and graphene are: 10%-0.3%, 8%-1%, 8%-2%, and 8%-3%, respectively.

[0021] 2) The spinning precursor solution is sucked into a 20 mL syringe, installed on a propulsion pump, connected to high voltage, the spinning machine voltage is set to 10-17 KV, the propulsion rate is set to 0.6-1.5 mL / h, the distance from the aluminum foil receiver is 8-20 cm, and electrospinning is performed at room temperature to obtain a graphene nanofiber film.

[0022] 3) The nanofiber membrane is cut into rectangular films of 100 mm × 100 mm, and laid in a mold in sequence according to the mass fraction of graphene in the fiber membrane. After the laying is completed, the impregnation liquid is introduced into the mold to impregnate the multi-layer fiber membrane as a whole. After curing, the final composite material is obtained.

[0023] Example 2

[0024] The method for preparing the multi-layer broadband graphene / MXene absorbing laminate structure of this embodiment comprises the following steps:

[0025] 1) A certain amount of polyvinyl pyrrolidone (PVP) was fully dissolved in anhydrous ethanol and magnetically stirred for 2 h until the solution was clear and transparent to obtain a 10 wt% PVP solution. Subsequently, a certain mass of MXene powder was added and magnetically stirred until fully dissolved to obtain MXene spinning precursor solutions with mass fractions of 0.5%, 1%, 1.5%, 2%, 2.5%, and 3%, respectively.

[0026] 2) The spinning precursor solution is sucked into a 20 mL syringe, installed on a propulsion pump, connected to high voltage, the spinning machine voltage is set to 10-17 KV, the propulsion rate is set to 0.6-1.5 mL / h, the distance from the aluminum foil receiver is 8-20 cm, and electrospinning is performed at room temperature to obtain a MXene nanofiber film.

[0027] 3) The nanofiber membrane is cut into rectangular films of 100 mm × 100 mm and laid in the mold in sequence according to the mass fraction of MXene in the fiber membrane. After the laying is completed, the impregnation liquid is introduced into the mold to impregnate the multi-layer fiber membrane as a whole. After curing, the final composite material is obtained.

[0028] Example 3

[0029] The method for preparing the multi-layer broadband graphene / MXene absorbing laminate structure of this embodiment comprises the following steps:

[0030] 1) A certain amount of polyacrylonitrile (PAN) powder is dissolved in N,N-dimethylformamide (DMF) solvent and magnetically stirred at room temperature for more than 8 hours. A certain mass fraction of defatted graphene powder is added to the polyacrylonitrile solution and magnetically stirred for more than 24 hours to obtain a graphene spinning precursor solution. In the solution, the mass fraction combinations of polyacrylonitrile and graphene are: 10%-0.3%, 8%-1%, 8%-2%, and 8%-3%, respectively.

[0031] 2) A certain amount of polyvinyl pyrrolidone (PVP) was fully dissolved in anhydrous ethanol and magnetically stirred for 2 h until the solution was clear and transparent to obtain a 10 wt% PVP solution. Subsequently, a certain mass of MXene powder was added and magnetically stirred until fully dissolved to obtain MXene spinning precursor solutions with mass fractions of 0.5%, 1%, 1.5%, 2%, 2.5%, and 3%, respectively.

[0032] 3) The spinning precursor solution is sucked into a 20 mL syringe, installed on a propulsion pump, connected to high voltage, the spinning machine voltage is set to 10-17 KV, the propulsion rate is set to 0.6-1.5 mL / h, the distance from the aluminum foil receiver is 8-20 cm, and electrospinning is performed at room temperature to obtain graphene and MXene nanofiber films.

[0033] 4) The nanofiber membrane is cut into rectangular films of 100 mm × 100 mm, and laid in the mold in sequence according to the mass fraction of graphene and MXene in the fiber membrane. After the laying is completed, the impregnation liquid is introduced into the mold to impregnate the multi-layer fiber membrane as a whole. After curing, the final composite material is obtained.

[0034] Experimental example

[0035] The electromagnetic wave absorption performance of the multi-layer broadband graphene / MXene absorbing laminate structure prepared in Example 3 was tested.

[0036] The composite material is tested for electromagnetic parameters of the graphene / MXene absorbing laminate structure by a waveguide method as required, and then the absorbing performance of the material is deduced, and the test frequency bands are 2.60-3.95GHz, 3.95-5.85GHz, 5.85-8.2GHz, 8.2-312.4GHz, and 12.4-18GHz. The graphene / MXene absorbing laminate structure prepared by the present invention can improve the electromagnetic wave absorption performance of the material.

[0037] It can be seen from the above embodiments that the present invention provides a multi-layer broadband graphene / MXene absorbing laminated structure, which utilizes the advantages of high conductivity, high dielectric constant, etc. of graphene and MXene, and composites them with high molecular polymers to prepare a laminated absorbing structure, giving full play to the high dielectric properties of graphene and MXene. At the same time, according to the impedance gradient design, the fiber membranes with different absorbing characteristics are arranged and laid in an orderly manner, which can improve the impedance matching characteristics and enhance the microwave absorption capacity.

[0038] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. Electrospinning technology is used to construct a multi-layer broadband graphene / MXene absorbing laminate structure and its preparation method, characterized by: The following steps are involved: Graphene nanofiber membranes and MXene nanofiber membranes were prepared respectively by electrospinning. After drying, their electromagnetic parameters were measured. The stacking order and method were designed according to the impedance matching principle and the attenuation maximization principle. After stacking, the multilayer fiber membrane was immersed in the impregnation liquid as a whole. After curing, the final composite material was obtained.

2. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to claim 1, characterized in that: Using electrospinning technology, the spinning machine voltage is 10-17KV, the propulsion rate is 0.6-1.5mL / h, the distance from the aluminum foil receiver is 8-20cm, and the electrospinning temperature is 15℃-40℃.

3. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to claim 1, characterized in that: The added mass fraction of graphene in the graphene nanofiber membrane is 0.3%-3%.

4. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to claim 1, characterized in that: The added mass fraction of MXene in the MXene nanofiber membrane is 0.5%-5%.

5. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to claim 1, characterized in that: Methods for drying the fiber membrane include, but are not limited to, vacuum heating drying, natural drying, and air drying.

6. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to any one of claims 1 to 4, characterized in that: The preparation steps of graphene nanofiber membrane are as follows: adding a certain mass fraction of defatted graphene powder to a mixed solution of polyacrylonitrile (PAN) and N,N-dimethylformamide (DMF), magnetically stirring for more than 24 hours, to obtain a graphene spinning precursor solution, wherein the mass fraction of PAN in the precursor solution is 6%-10%.

7. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to any one of claims 1 to 4, characterized in that: The preparation steps of MXene nanofiber membrane are as follows: fully dissolve polyvinyl pyrrolidone (PVP) in anhydrous ethanol to form a mixed solution with a PVP mass fraction of 10wt%, magnetically stir until the solution is clear and transparent, and obtain a mixed solution with a PVP mass fraction of 10wt%, then add a certain mass of MXene powder, and magnetically stir until it is fully dissolved.

8. The method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure according to any one of claims 1 to 4, characterized in that: The nanofiber membrane is cut into a rectangular film of 100mm×100mm. According to the impedance gradient design, 3-6 layers of the nanofiber membrane are laid in sequence. After the laying is completed, the multi-layer fiber membrane is immersed in the impregnation liquid as a whole. After curing, the final composite material is obtained.

9. A graphene / MXene absorbing laminate structure prepared by the method for preparing a multi-layer broadband graphene / MXene absorbing laminate structure as described in any one of claims 1 to 8.

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