Heterogeneous element doped transition metal disulfide electromagnetic wave absorbent and preparation method thereof
Through the method of heterogeneous element doping, the defects of transition metal disulfide are increased, and the shortcomings of wave absorption performance and frequency bandwidth in the prior art are solved, efficient electromagnetic wave absorption effect is achieved, and the preparation process is simplified.
Patent Information
- Application Number
- CN202510297146.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-13
- Publication Date
- 2025-05-13
AI Technical Summary
Existing transition metal disulfide electromagnetic wave absorbers have challenges in improving the absorption performance and wideband electromagnetic wave absorption, especially because the process is complex, costly and difficult to meet the requirements of the thin thickness and absorption frequency bandwidth of the absorbing material.
Through heterogeneous element doping, the defects of transition metal disulfide are increased, and their dipole polarization losses are enhanced, thereby improving the absorbance performance. This method is realized by a one-step hydrothermal method, with a simple preparation process and low cost, and through uniform doping element distribution, it meets the requirements of thin thickness and absorption frequency bandwidth of the absorbing material.
The absorption performance of transition metal disulfide electromagnetic wave absorber has been improved, and full absorption can be achieved in the Ku band, while reducing the preparation cost and complexity.
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Figure CN119976955A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of electromagnetic wave absorber preparation, and in particular to a heterogeneous element doped transition metal disulfide electromagnetic wave absorber and a preparation method thereof. Background Art
[0002] With the continuous development of modern electronic technology, especially the widespread use of radio communication equipment based on megahertz electromagnetic waves, the electromagnetic environment we live in has become increasingly complex. Electromagnetic pollution has become a new environmental problem after water, noise and air pollution. It not only interferes with the normal operation of communication electronic equipment, but also harms human health. Therefore, the development of electromagnetic wave absorbing materials with excellent performance and the disclosure of their absorbing mechanism are current hot issues.
[0003] Graphene-like transition metal disulfides (MS2, M = Mo, W, V, Nb) have been widely used in catalysis, energy storage, sensors and other fields. Due to their graphene-like honeycomb lattices and unique electronic structures, transition metal disulfides have been used as electromagnetic wave absorbers in the field of electromagnetic protection in recent years. However, how to further improve the wave absorption performance of transition metal disulfides and achieve broadband electromagnetic wave absorption is still a technical problem that needs to be solved.
[0004] Current research mostly combines transition metal disulfides with other materials such as carbon materials to construct heterogeneous interfaces to enhance interface polarization loss and thus improve their absorbing performance. However, this method is complex and costly, and because it is difficult to completely and evenly combine two different materials, it is also difficult to simultaneously meet the requirements of thin absorbing material thickness and wide absorption bandwidth. Summary of the invention
[0005] In view of the deficiencies of the above-mentioned prior art, the purpose of the present invention is to provide a heterogeneous element doped transition metal disulfide electromagnetic wave absorber and a preparation method thereof. The heterogeneous element doping of the present invention can enhance its dipole polarization loss by increasing the defects of the transition metal disulfide, thereby further improving its wave absorbing performance. This method can often be achieved through a one-step hydrothermal method, the preparation process is simple and the cost is low, and because the precursor solution of the heterogeneous element doped transition metal disulfide is a uniform single-phase system, the doping elements are evenly distributed, which can simultaneously meet the two requirements of thin thickness of the absorbing material and wide absorption bandwidth.
[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:
[0007] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0008] Glycerol is added into water, and after stirring, aqueous ammonia is added thereto to obtain a first mixed solution.
[0009] Soluble vanadate and soluble molybdate are added into the first mixed solution, and stirred to obtain a second mixed solution.
[0010] An organic sulfur compound is added to the second mixed solution, and after stirring, a precursor solution of heterogeneous elements doped with transition metal disulfide is obtained. The precursor solution of Mo doped with VS2 is subjected to a hydrothermal reaction, cooled, and centrifuged to obtain an electromagnetic wave absorber.
[0011] The heterogeneous element doping of the present invention can enhance the dipole polarization loss of the transition metal disulfide by increasing its defects, thereby further improving its absorbing performance. This method can be achieved through a one-step hydrothermal method, and the preparation process is simple and low-cost. Moreover, since the precursor solution of the heterogeneous element doped transition metal disulfide is a uniform single-phase system, the doping elements are evenly distributed, which can simultaneously meet the two requirements of thin thickness and wide absorption bandwidth of the absorbing material.
[0012] In a preferred embodiment of the present invention, the soluble vanadate is ammonium metavanadate, sodium metavanadate or potassium metavanadate, and the soluble molybdate is ammonium molybdate tetrahydrate, sodium molybdate dihydrate or potassium molybdate.
[0013] In a preferred embodiment of the present invention, the organic sulfur compound is thioacetamide or thiourea.
[0014] In a preferred embodiment of the present invention, the molar ratio of the organic sulfur compound to the soluble molybdate is 40:0.2-0.6.
[0015] In a preferred embodiment of the present invention, the molar percentage of the soluble molybdate in the soluble vanadate is 5% to 15%.
[0016] In a preferred embodiment of the present invention, the hydrothermal reaction temperature is 140° C. to 200° C., and the hydrothermal reaction time is 10 h to 24 h.
[0017] In a preferred embodiment of the present invention, the volume ratio of glycerol to water is 30:40-80, and the volume ratio of glycerol to aqueous ammonia is 30:4-12.
[0018] In a preferred embodiment of the present invention, the usage ratio of glycerol to soluble molybdate is 30 mL: 0.2 mmol to 0.6 mmol.
[0019] Another object of the present invention is to provide a heterogeneous element doped transition metal disulfide electromagnetic wave absorber prepared by any of the preparation methods described above.
[0020] Compared with the prior art, the present invention has the following beneficial effects:
[0021] The preparation method of the electromagnetic wave absorber of the present invention comprises the following steps: firstly mixing glycerol with water and ammonia water to prepare a first mixed solution, then adding soluble vanadate and soluble molybdate into the first mixed solution to prepare a second mixed solution, and finally adding an organic sulfur compound into the second mixed solution for physical mixing to obtain a precursor solution of a heterogeneous element doped with a transition metal disulfide, and subjecting the precursor solution of the heterogeneous element doped with the transition metal disulfide to hydrothermal treatment to obtain the electromagnetic wave absorber. The heterogeneous element doping of the present invention can enhance the dipole polarization loss of the transition metal disulfide by increasing the defects of the transition metal disulfide, thereby further improving the wave absorbing performance thereof. The method can be realized by a one-step hydrothermal method, and the preparation process is simple and the cost is low. Moreover, since the precursor solution of the heterogeneous element doped with the transition metal disulfide is a uniform single-phase system, the doping elements are evenly distributed, and the two requirements of thin thickness and wide absorption bandwidth of the wave absorbing material can be met at the same time. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is the precursor solution of Mo-doped VS2 in Example 1 of the present invention.
[0023] Figure 2 Scanning electron microscope images of samples prepared in Examples 1 to 3 of the present invention and Comparative Example 1, (a) VS2, (b) VS2-5%Mo, (c) VS2-10%Mo, (d) VS2-15%Mo, (e) to (h) EDS element distribution diagrams of VS2-10%Mo.
[0024] Figure 3 These are X-ray diffraction spectra of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo prepared in the present invention.
[0025] Figure 4 The X-ray photoelectron spectrum of VS2-10% Mo of the present invention, (a) is a wide scan spectrum, (b) to (d) are the corresponding high-resolution spectra.
[0026] Figure 5 (a) Real part of dielectric constant and (b) imaginary part of dielectric constant of prepared VS2, VS2-5%Mo, VS2-10%Mo and VS2-15%Mo.
[0027] Figure 6 These are the reflection loss diagrams of (a) VS2, (b) VS2-5%Mo, (c) VS2-10%Mo, and (d) VS2-15%Mo of the present invention.
[0028] Figure 7 These are the impedance matching diagrams of (a) VS2, (b) VS2-5% Mo, (c) VS2-10% Mo, and (d) VS2-15% Mo of the present invention, and (e) is the attenuation constant diagram. DETAILED DESCRIPTION
[0029] The following is a detailed description of the technical solutions in the embodiments of the present invention in combination with the preferred embodiments and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0030] It should be noted that all professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods.
[0031] Example 1
[0032] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0033] (1) Dissolve 30 mL of propylene glycol in 40 mL of water, stir evenly, and add 4 mL of aqueous ammonia, which is referred to as solution A.
[0034] (2) 4 mmol of ammonium metavanadate and 0.2 mmol of ammonium molybdate tetrahydrate were added to the solution A and stirred for three hours. This was recorded as solution B.
[0035] (3) 40 mmol of thioacetamide was added to the B solution and stirred for two hours to obtain a precursor solution of Mo-doped VS2, such as Figure 1 As shown, the precursor solution was charged into a 100 mL hydrothermal autoclave and subjected to hydrothermal treatment at 180° C. for 24 h. After cooling, the sample was centrifuged and dried to obtain a Mo-doped VS2 electromagnetic absorber, which was recorded as VS2-5%Mo.
[0036] Example 2
[0037] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0038] (1) Dissolve 30 mL of propylene glycol in 40 mL of water, stir evenly, and add 4 mL of aqueous ammonia, which is referred to as solution A.
[0039] (2) 4 mmol of ammonium metavanadate and 0.4 mmol of ammonium molybdate tetrahydrate were added to the solution A and stirred for three hours. This was recorded as solution B.
[0040] (3) 40 mmol of thioacetamide was added to the B solution, and after stirring for two hours, a precursor solution of Mo-doped VS2 was obtained. The precursor solution was charged into a 100 mL hydrothermal autoclave, and hydrothermally treated at 180° C. for 24 hours. After cooling, a sample was taken and centrifuged and dried to obtain a Mo-doped VS2 electromagnetic absorber, which was recorded as VS2-10% Mo.
[0041] Example 3
[0042] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0043] (1) Dissolve 30 mL of propylene glycol in 40 mL of water, stir evenly, and add 4 mL of aqueous ammonia, which is referred to as solution A.
[0044] (2) 4 mmol of ammonium metavanadate and 0.6 mmol of ammonium molybdate tetrahydrate were added to the solution A and stirred for three hours. This was recorded as solution B.
[0045] (3) 40 mmol of thioacetamide was added to the B solution, and after stirring for two hours, a precursor solution of Mo-doped VS2 was obtained. The precursor solution was charged into a 100 mL hydrothermal autoclave, and hydrothermally treated at 180° C. for 24 hours. After cooling, a sample was taken and centrifuged and dried to obtain a Mo-doped VS2 electromagnetic absorber, which was recorded as VS2-15% Mo.
[0046] Example 4
[0047] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0048] (1) Dissolve 30 mL of propylene glycol in 60 mL of water, stir evenly, and add 8 mL of aqueous ammonia, which is referred to as solution A.
[0049] (2) 4 mmol of ammonium metavanadate and 0.2 mmol of ammonium molybdate tetrahydrate were added to the solution A and stirred for three hours. This was recorded as solution B.
[0050] (3) Add 40 mmol of thioacetamide to the B solution, stir for two hours to obtain a precursor solution of Mo-doped VS2, put the precursor solution into a 100 mL hydrothermal autoclave, hydrothermally treat at 140° C. for 18 hours, cool down, take a sample, and centrifuge and dry to obtain a Mo-doped VS2 electromagnetic absorber.
[0051] Example 5
[0052] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0053] (1) Dissolve 30 mL of propylene glycol in 80 mL of water, stir evenly, and add 12 mL of aqueous ammonia, which is referred to as solution A.
[0054] (2) 4 mmol of ammonium metavanadate and 0.2 mmol of ammonium molybdate tetrahydrate were added to the solution A and stirred for three hours. This was recorded as solution B.
[0055] (3) 40 mmol of thioacetamide was added to the B solution, and the precursor solution of Mo-doped VS2 was obtained after stirring for two hours. The precursor solution was charged into a 100 mL hydrothermal autoclave, and hydrothermally treated at 200° C. for 10 hours. After cooling, a sample was taken and centrifuged and dried to obtain a Mo-doped VS2 electromagnetic absorber.
[0056] Comparative Example 1
[0057] A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber comprises the following steps:
[0058] (1) Dissolve 30 mL of propylene glycol in 40 mL of water, stir evenly, and add 4 mL of aqueous ammonia, which is referred to as solution A.
[0059] (2) Add 4 mmol of ammonium metavanadate to the solution A and stir for three hours, which is recorded as solution B.
[0060] (3) 40 mmol of thioacetamide was added to the B solution, and the precursor solution of Mo-doped VS2 was obtained after stirring for two hours. The precursor solution was charged into a 100 mL hydrothermal autoclave, and hydrothermally treated at 180° C. for 24 hours. After cooling, a sample was taken and centrifuged and dried to obtain a Mo-doped VS2 electromagnetic absorber, which was recorded as VS2.
[0061] Results Analysis
[0062] Figure 2 The following are the scanning electron microscope images of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo. As shown in the figure, VS2 presents a flower-like microsphere structure. After being doped with Mo, the microscopic morphology of Mo-doped VS2 does not change, and it still presents flower-like microspheres. The EDS element distribution diagram of VS2-10% Mo shows the uniform distribution of Mo, V and S on the surface of Mo-doped VS2 microspheres.
[0063] Figure 3 The following are the X-ray diffraction spectra of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo. As shown in the figure, all samples have the characteristic diffraction peaks of VS2 (001), (011), (012), (110), (004), (201) and (202) planes, indicating that the doping of Mo element does not change the crystal structure and purity of VS2.
[0064] Figure 4 It is the X-ray photoelectron spectrum of VS2-10% Mo. Figure 4 The characteristic peaks of three elements, V, S and Mo, appeared in the wide scan spectrum of (a), indicating the successful preparation of Mo-doped VS2. Figure 4 The high-resolution spectra corresponding to (b) to (d) also analyzed the chemical states and molecular structures of the three elements V, S, and Mo.
[0065] Figure 5 The dielectric constants of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo. As shown in the figure, compared with pure VS2, the real and imaginary parts of the dielectric constant of Mo-doped VS2 are improved, which shows that Mo doping can effectively enhance the dielectric properties of VS2, mainly because Mo doping can increase the defects of VS2 to enhance its dipole polarization.
[0066] Figure 6 The reflection loss of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo. As shown in the figure, the effective absorption bandwidth of pure VS2 is only 1.21GHz. After doping with Mo element, the absorbing performance of Mo-doped VS2 is significantly improved. When the thickness of the absorbing material is less than 1.7mm, the minimum reflection loss and effective absorption bandwidth of VS2-10% Mo can reach -54.36dB and 6.80GHz respectively, which can fully absorb below -10dB in the Ku band, and meet the two requirements of thin thickness of the absorbing material and wide absorption bandwidth.
[0067] Figure 7 The impedance matching and attenuation constants of VS2, VS2-5% Mo, VS2-10% Mo and VS2-15% Mo. As can be seen from the figure, Mo-doped VS2 has both excellent impedance matching and electromagnetic wave attenuation performance, which also explains why Mo-doped VS2 electromagnetic absorber has excellent wave absorbing performance.
[0068] In summary, the heterogeneous element doping of the present invention can enhance the dipole polarization loss of transition metal disulfide by increasing its defects, thereby further improving its absorbing performance. This method can be achieved by a one-step hydrothermal method, and the preparation process is simple and low-cost. Moreover, since the precursor solution of the heterogeneous element doped transition metal disulfide is a uniform single-phase system, the doping elements are evenly distributed, which can simultaneously meet the two requirements of thin thickness of the absorbing material and wide absorption bandwidth.
[0069] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the attached claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.
[0070] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.
Claims
1. A method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber, comprising the following steps: Adding glycerol to water, stirring and then adding ammonia water to obtain a first mixed solution; adding soluble vanadate and soluble molybdate to the first mixed solution and stirring to obtain a second mixed solution; An organic sulfur compound is added to the second mixed solution, and after stirring, a precursor solution of a heterogeneous element doped with a transition metal disulfide is obtained. The precursor solution of the heterogeneous element doped with a transition metal disulfide is subjected to a hydrothermal reaction, cooled, and centrifuged to obtain a heterogeneous element doped with a transition metal disulfide electromagnetic wave absorber.
2. The method for preparing the heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The soluble vanadate is ammonium metavanadate, sodium metavanadate or potassium metavanadate, and the soluble molybdate is ammonium molybdate tetrahydrate, sodium molybdate dihydrate or potassium molybdate.
3. The method for preparing the heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The organic sulfur compound is thioacetamide or thiourea.
4. The method for preparing the heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The molar ratio of the organic sulfur compound to the soluble molybdate is 40:0.2-0.
6.
5. The method for preparing the heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The molar percentage of soluble molybdate in soluble vanadate is 5% to 15%.
6. The method for preparing the heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The hydrothermal reaction temperature is 140°C to 200°C, and the hydrothermal reaction time is 10h to 24h.
7. The method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The volume ratio of glycerol to water is 30:40-80, and the volume ratio of glycerol to aqueous ammonia is 30:4-12.
8. The method for preparing a heterogeneous element doped transition metal disulfide electromagnetic wave absorber according to claim 1, characterized in that: The dosage ratio of glycerol to soluble molybdate is 30mL: 0.2mmol~0.6mmol.
9. A heterogeneous element doped transition metal disulfide electromagnetic wave absorber prepared by the preparation method according to any one of claims 1 to 8.