Topological insulator solid solution wave-absorbing material and preparation method thereof

Abstract

The invention discloses a topological insulator solid solution wave-absorbing material and a preparation method thereof, and belongs to the field of electromagnetic wave absorbing materials. The invention aims to solve the problem that an existing topological insulator wave-absorbing material is difficult to deal with a complex electromagnetic environment. The chemical expression of the invention is Mn < 1-x > Sn < x > Bi < 2 > Te < 4 >. The topological insulator single crystal grows through spontaneous nucleation. According to the invention, the Sn element is introduced for doping, the energy level position of the topological surface state is adjusted, and the intrinsic high impedance matching advantage of the topological insulator is combined, so that the excellent electromagnetic wave absorption performance is obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electromagnetic wave absorbing materials, and particularly relates to a topological insulator solid solution absorbing material and a preparation method thereof. BACKGROUND

[0002] The vigorous development of electronic information technology has promoted the commercial application of various electronic devices, but the electromagnetic pollution problem caused thereby is also increasingly serious. As a quantum material with surface conduction and bulk insulating characteristics, the easily adjustable surface state characteristics of topological insulator can produce optimal impedance matching performance and have high conductivity, and thus have considerable potential in the treatment of electromagnetic pollution.

[0003] The topological energy band characteristics of topological insulator make it have strong performance adjustability, which provides a basis for its application in the field of electromagnetic functional materials. In recent years, Hou Zhiling et al. (ACSAppl.Mater.Interfaces, 2019, 11, 33285-33291) prepared Bi2Te3 topological insulator nanosheets with different thicknesses by hydrothermal reaction, and realized the tuning of the absorbing performance through the thickness-dependent conductivity characteristics; in 2025, they again prepared Bi2Te3 topological insulator nanorods (J.Mater Sci.Technol., 2026, 244, 149-155) by hydrothermal reaction, realized optimal microwave absorbing performance, and further designed an electromagnetic-thermal-electric energy conversion device. However, the absorbing performance obtained by these works is insufficient, and it is still difficult to cope with complex electromagnetic environments. SUMMARY

[0004] In order to make up for the deficiencies of the existing topological insulator absorbing materials and realize the application of topological insulator solid solution in the field of electromagnetic functions, the application provides a topological insulator absorbing material and a preparation method thereof. The topological insulator single crystal is grown by spontaneous nucleation, and Mn 1-x Sn x Bi2Te4 absorbing material is synthesized. By introducing Sn element doping, the energy level position of the topological surface state is adjusted, and the intrinsic high impedance matching advantage of the topological insulator is combined, so that excellent electromagnetic wave absorbing performance is obtained.

[0005] In order to realize the above technical problems, the following technical solutions are adopted in the application: The purpose of the application is to provide a topological insulator solid solution absorbing material, which contains four metal elements: manganese, tin, bismuth and tellurium; and the chemical expression is Mn 1-x Sn x Bi2Te4, x =0.1-1.0.

[0006] Further limit, the crystal system of the wave-absorbing material is hexagonal crystal system, and the space group is R-3m.

[0007] Another object of the present application is to provide a preparation method of the topological insulator solid solution wave-absorbing material. Step 1, the stoichiometric ratio of manganese powder, tin powder, bismuth powder and tellurium powder is weighed, and then fully ground, placed in a double-layer quartz tube, and blocked with quartz wool in the inner tube to prevent the powder from being sucked out during vacuumizing, and then the quartz tube is sealed after vacuumizing, and placed in a muffle furnace, and the angle between the placement direction and the horizontal direction is greater than or equal to 60°. Step 2, sintering, the quartz tube is taken out and quenched to room temperature. Step 3, then the bulk body is taken out, cleaved and separated, the shiny plate-shaped part is taken, ground, and the wave-absorbing material is obtained.

[0008] Further limit, the mass purity of the manganese powder, tin powder, bismuth powder and tellurium powder is all greater than or equal to 99.9%.

[0009] Further limit, the sintering process is: heated to 650-800 DEG C within 200-400 min, and then immediately cooled to 590-600 DEG C at a rate of 0.1-0.01 DEG C / min, and kept for 10-21 d.

[0010] Further limit, the quartz tube is sealed by acetylene flame after reaching the vacuum degree.

[0011] Further limit, the vacuum degree is less than 10 -2 Pa.

[0012] Further limit, quenching in circulating water or liquid nitrogen.

[0013] Further limit, the bulk body is cleaved and separated along different cleavage planes of the single crystal.

[0014] The present application introduces Sn element solid solution, and the prepared Mn 1-x Sn x Bi2Te4 topological insulator material can optimize the topological surface state energy level position of the material, realize more optimal impedance matching performance, stronger electromagnetic wave absorption performance and wider effective absorption bandwidth. At the same time, the preparation process is simple and convenient, the equipment requirement is low, the cost is low, the raw material is safe and easy to obtain, and it is very important for preparing topological insulator electromagnetic wave absorption material.

[0015] Compared with the prior art, the present application has the following beneficial effects: This invention synthesizes a topological insulator solid solution absorbing material, wherein Sn doping modulates the energy level position of the topological surface states, raising both the surface states and Fermi level of the MnBi2Te4 material at room temperature from the valence state to the band gap. At the same time, Sn doping reduces the effective electronic mass of the MnBi2Te4 material, improves carrier mobility and conductivity, optimizes impedance matching performance and enhances conductivity loss, thereby improving electromagnetic wave absorption performance.

[0016] This invention precisely dops the Mn sites with a specific metal element Sn, thereby controllably synthesizing single-crystal and polycrystalline materials of topological insulator solid solution, fully exploring the potential of topological insulators in the field of electromagnetic attenuation.

[0017] The preparation process of this invention is simple to operate, can synthesize topological insulator materials in one step, has low equipment requirements, and is inexpensive.

[0018] For a deeper understanding of the features and technical content of this invention, please refer to the accompanying detailed description and drawings. It should be noted that the drawings are provided for illustrative purposes only and are not intended to limit the scope of the invention. Attached Figure Description

[0019] Figure 1 This is a physical image of the double-layer vacuum-encapsulated quartz tube used in this invention; Figure 2 The X-ray diffraction (XRD) patterns of the topological insulator single-crystal bulk materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention are shown. Figure 3 The X-ray diffraction (XRD) patterns of the topological insulator polycrystalline powder materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention are shown. Figure 4 The images shown are scanning electron microscope (SEM) images and elemental distribution maps (EDS) of the topological insulator single-crystal bulk materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention. Figure 5 The topological insulator material MnBi2Te4 in Example 1 of this invention ( x Electromagnetic wave absorption performance diagram (=0); Figure 6 The topological insulator material Mn in Example 2 of this invention 0.9 Sn 0.1 Bi2Te4 ( x Electromagnetic wave absorption performance diagram (=0.1); Figure 7 The topological insulator material Mn in Example 3 of this invention 0.8 Sn 0.2 Bi2Te4 (x =0.2) electromagnetic wave absorption performance graph; Figure 8 MnSnBi2Te4(topological insulator material) in Example 4 of the present invention 0.7 Sn 0.3 Bi2Te4( x =0.3) electromagnetic wave absorption performance graph; Figure 9 MnSnBi2Te4(topological insulator material) in Example 5 of the present invention 0.6 Sn 0.4 Bi2Te4( x =0.4) electromagnetic wave absorption performance graph; Figure 10 MnSnBi2Te4(topological insulator material) in Example 6 of the present invention 0.5 Sn 0.5 Bi2Te4( x =0.5) electromagnetic wave absorption performance graph; Figure 11 MnSnBi2Te4(topological insulator material) in Example 7 of the present invention 0.4 Sn 0.6 Bi2Te4( x =0.6) electromagnetic wave absorption performance graph; Figure 12 MnSnBi2Te4(topological insulator material) in Example 8 of the present invention 0.3 Sn 0.7 Bi2Te4( x =0.7) electromagnetic wave absorption performance graph; Figure 13 MnSnBi2Te4(topological insulator material) in Example 9 of the present invention 0.2 Sn 0.8 Bi2Te4( x =0.8) electromagnetic wave absorption performance graph; Figure 14 MnSnBi2Te4(topological insulator material) in Example 10 of the present invention 0.1 Sn 0.9 Bi2Te4( x =0.9) electromagnetic wave absorption performance graph; Figure 15 MnSnBi2Te4(topological insulator material) in Example 11 of the present invention x =1.0) electromagnetic wave absorption performance graph. DETAILED DESCRIPTION

[0020] The present invention will be described in detail below with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but should not be considered as limiting the present invention. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0021] The following manganese powder has a purity of 99.9%, tin powder has a purity of 99.99%, bismuth powder has a purity of 99.99%, and tellurium powder has a purity of 99.99%.

[0022] In this embodiment, the outer quartz tube has an outer diameter of approximately 17.8 mm, an inner diameter of approximately 14.9 mm, and a length of 15-25 cm. The inner quartz tube has an outer diameter of approximately 11.8 mm, an inner diameter of approximately 8.9 mm, and a length of 8-13 cm. After the inner tube is filled with a uniformly mixed raw material, the tube opening is plugged with quartz wool to prevent the raw material powder from being extracted during the vacuuming process.

[0023] Example 1 1. Weigh 0.2794g of manganese powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene (e.g. Figure 1 As shown in the figure, the quartz tube is placed in the muffle furnace at an angle of 75° to the horizontal direction. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 591℃ at a rate of 0.01℃ / min. After holding it at 591℃ for 14 days, take the quartz tube out and quench it in circulating water. IV. Remove the sintered block from the quartz tube, and use a blade to cleave the block along different cleavage planes of the single crystal. Grind the shiny plate-like portion for 1 hour to obtain MnBi2Te4 ( x =0) Polycrystalline powder sample.

[0024] Example 2 1. Weigh 0.2514g of manganese powder, 0.0604g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 592℃ at a rate of 0.01℃ / min. After holding it at 592℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.9 Sn 0.1 Bi2Te4 ( x =0.1) Polycrystalline powder sample.

[0025] Example 3 1. Weigh 0.2235g of manganese powder, 0.1207g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 593℃ at a rate of 0.01℃ / min. After holding it at 593℃ for 14 days, remove the quartz tube and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.8 Sn 0.2 Bi2Te4 ( x =0.2) Polycrystalline powder sample.

[0026] Example 4 1. Weigh 0.1956g of manganese powder, 0.1811g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 593℃ at a rate of 0.01℃ / min. After holding it at 593℃ for 14 days, remove the quartz tube and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn.0.7 Sn 0.3 Bi2Te4 ( x =0.3) Polycrystalline powder sample.

[0027] Example 5 1. Weigh 0.1676g of manganese powder, 0.2415g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 594℃ at a rate of 0.01℃ / min. After holding it at 594℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.6 Sn 0.4 Bi2Te4 ( x =0.4) Polycrystalline powder sample.

[0028] Example 6 1. Weigh 0.1397g of manganese powder, 0.3018g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 595℃ at a rate of 0.01℃ / min. After holding it at 595℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.5 Sn 0.5 Bi2Te4 ( x =0.5) Polycrystalline powder sample.

[0029] Example 7 1. Weigh 0.1117g of manganese powder, 0.3622g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 596℃ at a rate of 0.01℃ / min. After holding it at 596℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.4 Sn 0.6 Bi2Te4 ( x =0.6) Polycrystalline powder sample.

[0030] Example 8 1. Weigh 0.0838g of manganese powder, 0.4226g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 597℃ at a rate of 0.01℃ / min. After holding it at 597℃ for 14 days, remove the quartz tube and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.3 Sn 0.7 Bi2Te4 ( x =0.7) Polycrystalline powder sample.

[0031] Example 9 1. Weigh 0.0559g of manganese powder, 0.4829g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 598℃ at a rate of 0.01℃ / min. After holding it at 598℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.2 Sn 0.8 Bi2Te4 ( x =0.8) Polycrystalline powder sample.

[0032] Example 10 1. Weigh 0.0279g of manganese powder, 0.5433g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process. 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 599℃ at a rate of 0.01℃ / min. After holding it at 599℃ for 14 days, take the quartz tube out and quench it in circulating water. 4. Remove the sintered bulk from the quartz tube, and use a blade to cleave the bulk along different cleavage planes of the single crystal. Grind the shiny, plate-like portion for 1 hour to obtain Mn. 0.1 Sn 0.9 Bi2Te4 ( x =0.9) Polycrystalline powder sample.

[0033] Example 11 1. Weigh 0.6036g of tin powder, 2.1253g of bismuth powder, and 2.5954g of tellurium powder, grind them thoroughly for 30 minutes, place them in a double-layered quartz tube, and plug the inner tube with quartz wool to prevent the powder from being extracted during the vacuuming process; 2. Evacuate the quartz tube to 10°C. -3 Pa, after reaching the vacuum level, the quartz tube is sealed with acetylene and placed in a muffle furnace with its orientation at an angle of 75° to the horizontal. 3. Heat the quartz tube to 700℃ within 400 minutes, then immediately cool it down to 600℃ at a rate of 0.01℃ / min. After holding it at 600℃ for 14 days, take the quartz tube out and quench it in circulating water. IV. Remove the sintered block from the quartz tube, and use a blade to cleave the block along different cleavage planes of the single crystal. Grind the shiny plate-like portion for 1 hour to obtain SnBi2Te4 ( x =1.0) Polycrystalline powder sample.

[0034] The X-ray diffraction (XRD) patterns of the topological insulator single-crystal bulk materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention are as follows: Figure 2 As shown, by Figure 2 It can be seen that all samples have high equidistant peaks, proving the successful synthesis of single crystals. The peak around 13° corresponds to (0006), and the peak around 46° corresponds to (00021).

[0035] The X-ray diffraction (XRD) patterns of the topological insulator polycrystalline powder materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention are as follows: Figure 3 As shown, by Figure 3 It can be seen that the XRD patterns of all samples correspond to their R-3m space group; Scanning electron microscope (SEM) images and elemental distribution maps (EDS) of the topological insulator single-crystal bulk materials in Examples 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 of this invention are as follows: Figure 4 As shown, by Figure 4 It can be seen that all doped samples exhibit obvious layering characteristics, presenting millimeter-scale plate-like single crystals. The edges of the single crystals show obvious layering and wrinkling, and the layers are easily separated, corresponding to the van der Waals interactions between the layers of MnBi2Te4 and SnBi2Te4 materials. EDS elemental distribution images show that the elemental proportions are uniformly distributed, the (001) surface of the single crystal is flat, with some polycrystalline debris attached, and a small number of strip-like tear marks generated during sample processing. These characteristics collectively indicate that millimeter-scale plate-like single crystal samples were successfully prepared under different doping compositions. In Example 1 of this invention, the topological insulator material MnBi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0) is shown in the figure. Figure 5 As shown, by Figure 5 It can be seen that the deepest reflection loss of MnBi2Te4 is -42.2dB, and the effective absorption bandwidth is 1.76GHz; In Example 2 of this invention, the topological insulator material Mn 0.9 Sn 0.1 Bi2Te4 ( x The electromagnetic wave absorption performance diagram with a ratio of 0.1 is shown in the figure below. Figure 6 As shown, by Figure 6 It can be seen that Mn 0.9 Sn 0.1The deepest reflection loss of Bi2Te4 is -22.4dB, and the effective absorption bandwidth is 2.64GHz; In Example 3 of this invention, the topological insulator material Mn 0.8 Sn 0.2 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.2) is shown in the figure. Figure 7 As shown, by Figure 7 It can be seen that Mn 0.8 Sn 0.2 The deepest reflection loss of Bi2Te4 is -15.3dB, and the effective absorption bandwidth is 2.56GHz; In Example 4 of this invention, the topological insulator material Mn 0.7 Sn 0.3 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.3) is shown in the figure. Figure 8 As shown, by Figure 8 It can be seen that Mn 0.7 Sn 0.3 The deepest reflection loss of Bi2Te4 is -19.5dB, and the effective absorption bandwidth is 3.20GHz; In Example 5 of this invention, the topological insulator material Mn 0.6 Sn 0.4 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.4) is shown in the figure. Figure 9 As shown, by Figure 9 It can be seen that Mn 0.6 Sn 0.4 The deepest reflection loss of Bi2Te4 is -50.5dB, and the effective absorption bandwidth is 3.36GHz; In Example 6 of this invention, the topological insulator material Mn 0.5 Sn 0.5 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.5) is shown in the figure. Figure 10 As shown, by Figure 10 It can be seen that Mn 0.5 Sn 0.5 The deepest reflection loss of Bi2Te4 is -56.1dB, and the effective absorption bandwidth is 3.84GHz; In Example 7 of this invention, the topological insulator material Mn 0.4 Sn 0.6 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.6) is shown in the figure. Figure 11 As shown, by Figure 11 It can be seen that Mn 0.4 Sn 0.6The deepest reflection loss of Bi2Te4 is -34.9dB, and the effective absorption bandwidth is 4.32GHz; In Example 8 of this invention, the topological insulator material Mn 0.3 Sn 0.7 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.7) is shown in the figure. Figure 12 As shown, by Figure 12 It can be seen that Mn 0.3 Sn 0.7 The deepest reflection loss of Bi2Te4 is -27.3dB, and the effective absorption bandwidth is 4.08GHz; In Example 9 of this invention, the topological insulator material Mn 0.2 Sn 0.8 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.8) is shown in the figure. Figure 13 As shown, by Figure 13 It can be seen that Mn 0.2 Sn 0.8 The deepest reflection loss of Bi2Te4 is -24.1dB, and the effective absorption bandwidth is 4.08GHz; In Example 10 of this invention, the topological insulator material Mn 0.1 Sn 0.9 Bi2Te4 ( x The electromagnetic wave absorption performance diagram of (=0.9) is shown in the figure. Figure 14 As shown, by Figure 14 It can be seen that Mn 0.1 Sn 0.9 The deepest reflection loss of Bi2Te4 is -28.4dB, and the effective absorption bandwidth is 3.92GHz; In Example 11 of this invention, the topological insulator material SnBi2Te4 ( x The electromagnetic wave absorption performance diagram of (=1.0) is shown in the figure. Figure 15 As shown, by Figure 15 It can be seen that the deepest reflection loss of SnBi2Te4 is -17.2dB, and the effective absorption bandwidth is 3.60GHz.

[0036] The specific embodiments of the present invention have been described in detail above. It should be noted that the present invention is not limited to the specific embodiments described above. Various modifications or alterations can be made by those skilled in the art without departing from the scope of protection defined by the claims, and all such modifications or alterations fall within the scope of the present invention.

Claims

1. A topological insulator solid solution absorbing material, characterized in that, Its chemical formula is Mn 1-x Sn x Bi2Te4, x =0.1-1.

0.

2. The microwave absorbing material according to claim 1, characterized in that, x= 0.1、0.2、0.3、0.4、0.5、0.6、0.7、0.8、0.9、1.0。 3. The microwave absorbing material according to claim 1, characterized in that, The microwave absorbing material has a hexagonal crystal system and a space group of R-3m.

4. The method for preparing the microwave absorbing material as described in claim 1, 2, or 3, characterized in that, Includes the following steps: Step 1: Weigh out the stoichiometric ratio of manganese powder, tin powder, bismuth powder, and tellurium powder, grind them thoroughly, place them in a double-layered quartz tube, plug the inner tube with quartz wool, evacuate and seal the quartz tube, and place it in a muffle furnace with the angle between its placement direction and the horizontal direction greater than or equal to 60°. Step 2: Sintering. After removing the quartz tube, quench it to room temperature. Step 3: Then remove the block, cleave and separate it, take the shiny plate-like part, grind it, and obtain the microwave absorbing material.

5. The method according to claim 4, characterized in that, The purity of manganese powder, tin powder, bismuth powder, and tellurium powder is ≥99.9%.

6. The method according to claim 4, characterized in that, Sintering process: Heat to 650℃-800℃ within 200min-400min, then immediately cool to 590℃-600℃ at a rate of 0.1℃ / min-0.01℃ / min, and hold for 10d-21d.

7. The method according to claim 4, characterized in that, Vacuum degree below 10 -2 Pa.

8. The method according to claim 4, characterized in that, Quenching in circulating water or liquid nitrogen.

9. The method according to claim 4, characterized in that, Cleavage of the bulk is separated along different cleavage planes of the single crystal.

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