A Ni3InC 0.5 Wave-absorbing material and preparation method

Abstract

The present invention discloses a Ni3InC 0.5 absorbing material and a preparation method thereof. (1) Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O are dispersed in N,N-dimethylformamide (DMF), and after magnetic stirring, liquid A is obtained; (2) terephthalic acid (PTA) and triethylamine (TEA) are dispersed in DMF, and after magnetic stirring, liquid B is obtained; (3) liquid B is poured into liquid A, and stirring is continued to obtain a Ni3InC 0.5 precursor solution; (4) the solution obtained in step (3) is filtered by a circulating water suction filter to obtain a gel-like sample; (5) the sample obtained in step (4) is calcined under a nitrogen atmosphere, and after natural cooling to room temperature, Ni3InC 0.5 is obtained. The present invention has the characteristics of simple process and low cost, and for the first time, this material is applied to the field of wave absorption.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave absorbing materials, and particularly relates to a Ni3InC 0.5 microwave absorbing material and a preparation method thereof. Background Technique

[0002] With the development of communication technology and modern science and technology, it is of great significance to construct microwave absorbing materials with light weight, strong absorption, thin thickness, and wide frequency characteristics to weaken the influence of electromagnetic radiation.

[0003] In recent years, metal carbides with multiple loss mechanisms such as dielectric loss and magnetic loss have stood out. As a non-stoichiometric bimetallic carbide, Ni3ZnC 0.7 has the advantages of precise composition regulation, low synthesis cost, and easy formation of defects. Therefore, it has great development potential in the field of microwave absorption. Some researchers have compounded it with various carbon materials to enhance the dielectric properties and obtained excellent microwave absorption performance.

[0004] Ni3InC 0.5 has many similarities with Ni3ZnC 0.7 but is more widely applied in the fields of catalysis, batteries, and other energy fields and has never been applied in the field of microwave absorption, leaving a research gap.

[0005] At present, the intrinsic electromagnetic parameters and microwave absorption performance of Ni3InC 0.5 are unknown. Among the reported preparation methods of Ni3InC 0.5 the solid-phase method (https: / / doi.org / 10.1039 / d3dt01331f) is widely used. Its synthetic raw materials are hydroxides of Ni and In. However, hydroxides may undergo side reactions under certain reaction conditions, which not only reduces the yield and purity of the product but also may affect the performance of the final material. At the same time, hydroxides may be more likely to absorb moisture or decompose during storage and handling. Summary of the Invention

[0006] In order to overcome the above technical problems, the purpose of the present invention is to provide a Ni3InC 0.5 microwave absorbing material and a preparation method thereof, and the material preparation method has the characteristics of good chemical uniformity and simple operation.

[0007] The technical solution adopted by the present invention is:

[0008] A Ni3InC 0.5The microwave absorbing material is mainly composed of spherical particles. A small number of spherical particles are sintered and agglomerated to form a small amount of rod-shaped particles. The diameter of the spherical particles is about 50 - 80 nm, the surface is relatively smooth and evenly distributed; the length of the rod-shaped particles is about 100 - 150 nm, and the diameter is 50 - 80 nm. The surfaces of both types of particles are Ni3InC 0.5 phase.

[0009] The spherical particles have good symmetry, can uniformly scatter the incident electromagnetic wave, reduce the reflection of the signal, and improve the microwave absorption efficiency. The presence of the rod-shaped particles can introduce asymmetry, promote multiple reflections and scattering of the electromagnetic wave, and thus further enhance the microwave absorption effect.

[0010] A preparation method of Ni3InC 0.5 microwave absorbing material, comprising the following steps;

[0011] (1) Disperse Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O into N, N-dimethylformamide (DMF), and obtain liquid A after magnetic stirring;

[0012] (2) Disperse terephthalic acid (PTA) and triethylamine (TEA) into DMF, and obtain liquid B after magnetic stirring;

[0013] (3) Pour the liquid B obtained in step (2) into the liquid A obtained in step (1), and continue stirring to obtain a Ni3InC 0.5 precursor solution;

[0014] (4) Put the Ni3InC 0.5 precursor solution obtained in step (3) into a circulating water suction filter for suction filtration to obtain a gel-like sample;

[0015] (5) Take the gel-like sample obtained in step (4) and calcine it under a nitrogen atmosphere. After natural cooling to room temperature, a Ni3InC 0.5 microwave absorbing material is obtained.

[0016] In the step (1), Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O are dispersed into 125 - 300 mL of DMF; wherein, the molar ratio between Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O is 3:1.

[0017] By precisely controlling the molar ratio of nickel (Ni) and indium (In), it can ensure the formation of Ni3InC with a specific chemical composition in the subsequent reaction 0.5Precursor. During the synthesis process, DMF is used as a solvent, which helps dissolve and mix metal salts Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O, providing a homogeneous reaction environment for subsequent coordination reactions.

[0018] In step (1), magnetic stirring is carried out for 0.5 - 1 h.

[0019] In step (2), 7 - 10 mmol of PTA and 2 - 4 ml of TEA are dispersed in 100 - 200 ml of DMF. As an organic acid, PTA can participate in the reaction as a ligand or auxiliary ligand during the synthesis process, helping to form stable metal complexes; while TEA, as a base source in the reaction, is used to adjust the pH value of the reaction system. This ratio setting is more conducive to the complexation and stability of the product.

[0020] In step (2), magnetic stirring is carried out for 0.5 - 1 h.

[0021] In step (3), magnetic stirring is carried out for 1 - 20 h.

[0022] In step (5), the sample obtained in step (4) is heated to 700 - 900 °C at a heating rate of 5 °C / min under a nitrogen atmosphere and held for 10 - 12 h. At this calcination time and temperature, it can ensure the preparation of single-phase Ni3InC 0.5 .

[0023] The Ni3InC prepared in step (5) 0.5 material is applied to the field of wave absorption.

[0024] Advantages of the present invention:

[0025] The prominent substantial feature of the present invention is that for the first time, the solution precipitation method is used to prepare Ni3InC 0.5 and its intrinsic electromagnetic parameters and wave absorption performance are tested. Combining with the density of the material, it is found that under the condition of m(Ni3InC 0.5 ):m(paraffin)=20 - 60%, the minimum reflection loss of Ni3InC 0.5 is -35.37 dB, and the effective absorption bandwidth is 4.6 GHz, confirming that Ni3InC 0.5 has great development potential in the field of wave absorption. The excellent wave absorption performance is mainly attributed to the following aspects: First, Ni in the Ni3InC 0.5 material has excess unpaired electrons in the 3d orbitals. These unpaired electrons induce unique polarization losses, thus having a positive impact on the electromagnetic wave absorption performance; Second, in the high-frequency range, Ni3InC 0.5Due to their good electrical conductivity, the metals Ni and In in the material will generate eddy current effects in an externally applied electromagnetic field. This eddy current effect will cause electromagnetic energy to be converted into heat energy, thereby generating magnetic loss; at the same time, Ni3InC 0.5 The interfaces between particles will cause polarization relaxation phenomena, which are beneficial for the attenuation of electromagnetic waves through polarization loss; in addition, the presence of rod-shaped particles results in multiple reflections and scattering being dissipated, enhancing the electromagnetic wave absorption performance. Description of the Drawings

[0026] Figure 1 The X-ray diffraction pattern of the Ni3InC 0.5 material obtained in Example 1.

[0027] Figure 2 The scanning electron microscope image of the Ni3InC 0.5 material obtained in Example 1.

[0028] Figure 3 When m(Ni3InC 0.5 ):m(paraffin)=30% in Example 2, the performance diagram of the Ni3InC 0.5 material.

[0029] Figure 4 When m(Ni3InC 0.5 ):m(paraffin)=40% in Example 3, the performance diagram of the Ni3InC 0.5 material.

[0030] Figure 5 When m(Ni3InC 0.5 ):m(paraffin)=50% in Example 4, the performance diagram of the Ni3InC 0.5 material. Detailed Embodiments

[0031] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention. Embodiment

[0032] (1) Disperse 11.25 mmol Ni(CH3COO)2·4H2O and 3.75 mmol In(CH3COO)2·6H2O into 125 mL of DMF, and obtain liquid A after magnetic stirring for 0.5 h.

[0033] (2) Disperse 9 mmol of PTA and 2.125 ml of TEA into 100 ml of DMF, and after magnetic stirring for 0.5 h, obtain liquid B.

[0034] (3) Pour liquid B into liquid A, and continue stirring for 20 h to obtain the Ni3InC 0.5 precursor solution.

[0035] (4) Filter the solution obtained in step (3) using a circulating water suction filter to obtain a gel-like sample.

[0036] (5) Take the sample obtained in step (4), under a nitrogen atmosphere, heat it to 700 °C at a heating rate of 5 °C / min and hold for 10 h. After natural cooling to room temperature, obtain Ni3InC 0.5 .

[0037] The synthesized Ni3InC 0.5 material was characterized by X-ray diffractometer. The results are as Figure 1 shown. Diffraction peaks appear at 2θ = 23.51°, 33.5°, 41.34°, 48.1°, 70.42° and 85.02°, which can be indexed to the standard card Ni3InC 0.5 PDF#28 - 0468, and there are no other impurity phases, proving that the pure-phase Ni3InC 0.5 sample was successfully prepared. Subsequently, the morphology of Ni3InC 0.5 was characterized. As Figure 2 shown, it can be seen that under low-magnification scanning electron microscopy, it is mainly spherical particles, with a small number of rod-shaped particles. After magnification, it is found that the size of the spherical particles is about 50 - 80 nm, the surface is relatively smooth and evenly distributed. Example

[0038] Synthesis of Ni3InC 0.5 material and preparation of a test ring with a paraffin filling ratio of 30% are as follows:

[0039] (1) Disperse 11.25 mmol of Ni(CH3COO)2·4H2O and 3.75 mmol of In(CH3COO)2·6H2O into 125 mL of DMF, and after magnetic stirring for 0.5 h, obtain liquid A.

[0040] (2) Disperse 9 mmol of PTA and 2.125 ml of TEA into 100 ml of DMF, and after magnetic stirring for 0.5 h, obtain liquid B.

[0041] (3) Pour liquid B into liquid A, and continue stirring for 1 h to obtain the Ni3InC 0.5 precursor solution.

[0042] (4) Filter the solution obtained in step (3) using a circulating water suction filter to obtain a gel-like sample.

[0043] (5) Take the sample obtained in step (4), under a nitrogen atmosphere, heat it to 700 °C at a heating rate of 5 °C / min and hold for 10 h. After natural cooling to room temperature, Ni3InC is obtained. 0.5 .

[0044] (6) Weigh 0.03 g of Ni3InC 0.5 powder and 0.07 g of paraffin (m(Ni3InC 0.5 ):m(paraffin) = 30%) and mix them. Place the mixture in a container and melt the paraffin using the heating function of a constant-temperature magnetic stirrer. Gently stir with a spatula until evenly mixed, then place it in a mold and apply pressure to prepare a test ring with an outer diameter of 7 mm, an inner diameter of 3.04 mm, and a paraffin filling ratio of 30% Ni3InC 0.5 test ring.

[0045] Use a vector network analyzer (3656D) to test the microwave absorption performance of the test ring with a paraffin filling ratio of 30% Ni3InC prepared in Example 1. As 0.5 shown, the minimum reflection loss of Ni3InC Figure 3 is -38.76 dB, and the effective absorption bandwidth is 3.82 GHz. 0.5 Example

[0046] Synthesis of Ni3InC 0.5 material and preparation of a test ring with a paraffin filling ratio of 40% are as follows:

[0047] (1) Disperse 11.25 mmol of Ni(CH3COO)2·4H2O and 3.75 mmol of In(CH3COO)2·6H2O into 125 mL of DMF, and after magnetic stirring for 0.5 h, obtain liquid A.

[0048] (2) Disperse 9 mmol of PTA and 2.125 ml of TEA into 100 ml of DMF, and after magnetic stirring for 0.5 h, obtain liquid B.

[0049] (3) Pour liquid B into liquid A and continue stirring for 1 h to obtain a Ni3InC 0.5 precursor solution.

[0050] (4) Filter the solution obtained in step (3) using a circulating water suction filter to obtain a gel-like sample.

[0051] (5) Take the sample obtained in step (4), and under the condition of nitrogen atmosphere, heat it to 700 °C at a heating rate of 5 °C / min and hold for 10 h. After natural cooling to room temperature, Ni3InC is obtained. 0.5 .

[0052] (6) Weigh 0.04 g of Ni3InC 0.5 powder and 0.06 g of paraffin (m(Ni3InC 0.5 ):m(paraffin)=40%) and mix them. Place the mixture in a container and melt the paraffin using the heating function of a constant temperature magnetic stirrer. Gently stir with a spatula until evenly mixed, then place it in a mold and apply pressure to prepare a test ring of Ni3InC with a paraffin filling ratio of 40%, an outer diameter of 7 mm, and an inner diameter of 3.04 mm. 0.5 Test ring.

[0053] Use a vector network analyzer (3656D) to test the microwave absorption performance of the test ring of Ni3InC with a paraffin filling ratio of 40% prepared in Example 2. As 0.5 shown, the minimum reflection loss of Ni3InC Figure 4 is -35.37 dB, and the effective absorption bandwidth is 4.6 GHz. 0.5 Example

[0054] Synthesis of Ni3InC 0.5 material and preparation of a test ring with a paraffin filling ratio of 50% are as follows:

[0055] (1) Disperse 11.25 mmol of Ni(CH3COO)2·4H2O and 3.75 mmol of In(CH3COO)2·6H2O into 125 mL of DMF, and after magnetic stirring for 0.5 h, liquid A is obtained.

[0056] (2) Disperse 9 mmol of PTA and 2.125 ml of TEA into 100 ml of DMF, and after magnetic stirring for 0.5 h, liquid B is obtained.

[0057] (3) Pour liquid B into liquid A and continue stirring for 1 h to obtain a Ni3InC 0.5 precursor solution.

[0058] (4) Filter the solution obtained in step (3) using a circulating water suction filter to obtain a gel-like sample.

[0059] (5) Take the sample obtained in step (4), and under the condition of nitrogen atmosphere, heat it to 700 °C at a heating rate of 5 °C / min and hold for 10 h. After natural cooling to room temperature, Ni3InC 0.5 is obtained.

[0060] (6) Weigh 0.05 g of Ni3InC 0.5 powder and 0.05 g of paraffin (m(Ni3InC 0.5 ):m(paraffin)=50%) and mix them. Place the mixture in a container and melt the paraffin using the heating function of a constant-temperature magnetic stirrer. Gently stir with a spatula until evenly mixed, then place it in a mold and apply pressure to prepare a paraffin-filled Ni3InC 0.5 test ring with an outer diameter of 7 mm and an inner diameter of 3.04 mm and a paraffin filling ratio of 50%.

[0061] Use a vector network analyzer (3656D) to test the microwave absorption performance of the paraffin-filled Ni3InC 0.5 test ring prepared in Example 3. As Figure 5 shown, the minimum reflection loss of Ni3InC 0.5 is -19.45 dB, and the effective absorption bandwidth is 3.98 GHz.

[0062] In summary, the above are only embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A Ni3InC 0.5 microwave absorbing material, characterized in that Spherical particles are the main component, and a small number of spherical particles are sintered and agglomerated to form a small amount of rod-shaped particles. The diameter of the spherical particles is 50 - 80 nm, the surface is relatively smooth and evenly distributed; the length of the rod-shaped particles is 100 - 150 nm, and the diameter is 50 - 80 nm. The surfaces of both types of particles are Ni3InC 0.5 phase.

2. A preparation method of an Ni3InC 0.5 absorbing material, characterized in that Including the following steps; (1) Disperse Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O into N, N-dimethylformamide (DMF), and obtain liquid A after magnetic stirring; (2) Disperse terephthalic acid (PTA) and triethylamine (TEA) into DMF, and obtain liquid B after magnetic stirring; (3) Pour the liquid B obtained in step (2) into the liquid A obtained in step (1), and continue stirring to obtain Ni3InC 0.5 Precursor solution; (4) The Ni3InC 0.5 precursor solution obtained in step (3) is placed in a circulating water suction filter for suction filtration to obtain a gel-like sample; (5) The gel-like sample obtained in step (4) is calcined under a nitrogen atmosphere. After being naturally cooled to room temperature, Ni3InC is obtained. 0.5 Wave-absorbing material; In step (5), the sample obtained in step (4) is heated to 700 - 900 °C at a heating rate of 5 °C / min under a nitrogen atmosphere and held for 10 - 12 h. At this calcination time and temperature, it is possible to ensure the preparation of single-phase Ni3InC 0.5 .

3. A method for preparing an Ni3InC 0.5 absorbing material, characterized in that In the step (1), disperse Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O into 125 - 300 mL of DMF; wherein, the molar ratio between Ni(CH3COO)2·4H2O and In(CH3COO)2·6H2O is 3:1; In the step (1), perform magnetic stirring for 0.5 - 1 h.

4. A preparation method of Ni3InC 0.5 absorbing material, characterized in that In the step (2), disperse 7 - 10 mmol of PTA and 2 - 4 mL of TEA into 100 - 200 mL of DMF; In the step (2), perform magnetic stirring for 0.5 - 1 h.

5. A preparation method of an Ni3InC 0.5 absorbing material, characterized in that In the step (3), perform magnetic stirring for 1 - 20 h.

6. An application of a Ni3InC 0.5 absorbing material, characterized in that The Ni3InC 0.5 material is applied to the field of wave absorption.

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