Two-dimensional structural composite material and method for manufacturing the same

Abstract

To provide a two-dimensional structural composite material and a manufacturing method for the same, two-dimensional structural composite material being a two-dimensional structural material and other functional materials that may improve functionality derived from the two-dimensional structural material.SOLUTION: The two-dimensional structural composite material is configured by an aerosol deposition film 20 of two-dimensional structural material particles 21 and functional material particles 22. The two-dimensional structural material particles 21 are laminated and show a c-axis orientation. The functional material particles 22 are encapsulated by the two-dimensional structural material particles 21.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a two-dimensional structural composite material and a method for producing the same. [Background technology]

[0002] Two-dimensional structural materials, exemplified by the nanocarbon material graphene, are layered materials bonded by strong covalent bonds in the in-plane direction and relatively weak van der Waals forces in the c-axis direction. Due to their unique electronic state resulting from their two-dimensional structure, they exhibit extremely high electrical conductivity, thermal conductivity, and mechanical strength in the in-plane direction. This has led to expectations for a wide range of applications, including conductive materials, radio wave absorbing materials, electronic materials, heat dissipation materials, and structural materials, and numerous two-dimensional structural materials composed of elements other than carbon are also being discovered.

[0003] As an electromagnetic wave absorbing material that can ensure electromagnetic wave absorption at frequencies of 10 GHz or higher, a composite material consisting of a matrix and a plurality of flaky graphite fillers dispersed in the matrix has been proposed (see, for example, Patent Document 1). The average angle θ of the smaller of the two angles formed between the basal surface of the flaky graphite filler and each of the two surfaces of the composite material is adjusted to 30° or less.

[0004] The loss of electromagnetic wave absorbers used in situations close to high-frequency sources (near-field), such as noise suppression in mobile communication devices like smartphones, is due to the sheet resistance R. S There are controllable eddy current losses and ferromagnetic resonance losses inherent to magnetic materials, and it is known that the former, eddy current losses, have a particularly large influence (see, for example, Patent Document 2). [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2019-134011 [Patent Document 2] Japanese Patent Publication No. 2006-279912 [Overview of the project] [Problems that the invention aims to solve]

[0006] However, the presence of a matrix made of thermoplastic resin or elastomer reduces the volume occupancy rate of the filler in the electromagnetic wave absorbing material, thus diluting the electromagnetic wave absorbing properties of the filler.

[0007] Two-dimensional structural materials, or graphite, are known to have low electrical resistance within the c-plane and exhibit significant electromagnetic wave absorption even on their own. However, when combined with high-resistance materials, the sheet resistance R S By adjusting these parameters, eddy current losses can be maximized, improving electromagnetic wave absorption characteristics in the near field. Furthermore, using magnetic materials in the composite structure can add the effect of ferromagnetic resonance loss, leading to further improvements in performance.

[0008] Therefore, the present invention aims to provide a two-dimensional structural composite material and a method for manufacturing the same, which is a composite material of a two-dimensional structural material and other functional materials, and which can improve the functionality derived from the two-dimensional structural material. [Means for solving the problem]

[0009] The two-dimensional structural composite material of the present invention is It is composed of an aerosol deposition film of two-dimensional structural material particles and functional material particles. Two-dimensional structural material particles are stacked to exhibit c-axis orientation. Functional material particles are encapsulated by two-dimensional structural material particles.

[0010] The present invention provides a method for producing a two-dimensional structural composite material, which includes the step of spraying a mixed powder of a two-dimensional structural material and a functional material onto a substrate according to an aerosol deposition method.

[0011] According to the two-dimensional structure composite material of this configuration, the volume occupancy of the two-dimensional structure material and the functional material particles can be improved by the amount that the matrix does not exist. For this reason, functions such as electromagnetic wave absorption characteristics derived from the two-dimensional structure material are not diluted, and the functions are assisted by the functional material particles.

Brief Description of the Drawings

[0012] [Figure 1] Schematic explanatory diagram of a two-dimensional structure composite material as an embodiment of the present invention. [Figure 2A] Scanning electron microscope photograph of sample 1 of the two-dimensional structure composite material. [Figure 2B] Scanning electron microscope photograph (high magnification) of sample 1 of the two-dimensional structure composite material. [Figure 3A] Explanatory diagram regarding the X-ray diffraction spectrum of sample 1. [Figure 3B] Explanatory diagram regarding the X-ray diffraction spectrum of sample 2. [Figure 3C] Explanatory diagram regarding the X-ray diffraction spectrum of sample 3. [Figure 3D] Explanatory diagram regarding the X-ray diffraction spectrum of sample 4. [Figure 3E] Explanatory diagram regarding the X-ray diffraction spectrum of sample 5. [Figure 4A] Explanatory diagram regarding the X-ray diffraction spectrum of reference sample 1. [Figure 4B] Explanatory diagram regarding the X-ray diffraction spectrum of reference sample 2. [Figure 4C] Explanatory diagram regarding the X-ray diffraction spectrum of reference sample 3. [Figure 5A] Explanatory diagram regarding the magnetization curve of sample 1. [Figure 5B] Explanatory diagram regarding the magnetization curve of sample 2. [Figure 5C] Explanatory diagram regarding the magnetization curve of sample 3. [Figure 5D] Explanatory diagram regarding the magnetization curve of sample 4. [Figure 5E] Explanatory diagram regarding the magnetization curve of sample 5. [Figure 6A] Explanatory diagram regarding the magnetization curve of reference sample 1. [Figure 6B] An explanatory diagram regarding the magnetization curve of reference sample 2. [Figure 6C] An explanatory diagram regarding the magnetization curve of reference sample 3. [Figure 7A] An explanatory diagram showing the evaluation results of the Ploss / Pin characteristics of sample 6. [Figure 7B] An explanatory diagram regarding the evaluation results of the return loss S11 of sample 6. [Figure 7C] An explanatory diagram regarding the evaluation results of the transmission attenuation S21 of sample 6. [Modes for carrying out the invention]

[0013] (composition) A two-dimensional structural composite material, schematically shown in Figure 1 as one embodiment of the present invention, is composed of an AD film 20 (aerosol deposition film) formed on a substrate 10. The AD film 20 is composed of a plurality of two-dimensional structural material particles 21 stacked in a c-axis orientation and a plurality of functional material particles 22 arranged to fill the gaps between the plurality of two-dimensional structural material particles 21.

[0014] As the substrate 10, a substrate made of at least one compound selected from the group consisting of various ceramics such as quartz, alumina, zirconia, silicon carbide, and silicon nitride, and flexible sheets such as polyethylene terephthalate (PET), acrylic, polyacetal, polycarbonate, polyethylene, polypropylene, polyimide, silicone rubber, and pyrolysis graphite is used.

[0015] The thickness of the AD film 20 is in the range of 0.1 to 2000 μm, preferably in the range of 1 to 10 μm. The porosity of the AD film 20 is in the range of 1% to 15%, preferably in the range of 1% to 5%. The sheet resistance R of the AD film SThe impedance is in the range of 0.1 to 1000 Ω, preferably in the range of 10 to 200 Ω. The mass ratio of the functional material particles 22 to the total mass of the two-dimensional structural material particles 21 and functional material particles 22 in the AD film 20 is in the range of 0.1 to 40 mass%, preferably in the range of 5 to 35 mass%, and more preferably in the range of 10 to 30 mass%.

[0016] The two-dimensional structural material particles 21 are a concept that encompasses not only single-layer two-dimensional structural materials but also multilayer two-dimensional structural material particles in which basal planes overlap. Materials having a single-layer or multilayer two-dimensional structure, such as graphene, hexagonal boron nitride (h-BN), TMDs such as MoS2, phosphorene (black phosphorus), and conductive carbides or nitrides such as MXene (maxine), may be used as the two-dimensional structural material. The average diameter of the two-dimensional structural material particles 21 is in the range of 0.1 to 100 μm, preferably 0.5 to 50 μm, more preferably 0.5 to 10 μm, and even more preferably 0.5 to 5 μm, and the thickness is in the range of 0.3 to 300 nm (1 to 1000 layers of two-dimensional structural material molecules), preferably 0.3 to 30 nm (1 to 100 layers of two-dimensional structural material molecules), and even more preferably 0.3 to 10 nm (1 to 30 layers of two-dimensional structural material molecules).

[0017] As functional material particles 22, for example, magnetic particles and / or dielectric particles are used. The average particle size of the functional material particles 22 is in the range of 0.1 to 1000 μm, preferably in the range of 0.5 to 100 μm, preferably in the range of 1 to 10 μm, and preferably in the range of 1 to 5 μm, and the thickness is in the range of 1 to 100 μm, preferably in the range of 1 to 50 μm. The mass ratio of the functional material powder to the total mass of the two-dimensional structural material powder and the functional material powder in the AD film raw material is in the range of 50 to 99.9 mass%, preferably in the range of 70 to 99 mass%, and more preferably in the range of 80 to 95 mass%.

[0018] As the magnetic material, at least one compound selected from the group consisting of various element-substituted compounds based on carbonyl iron nanoparticles, iron-based alloys containing reduced iron nanoparticles, strontium ferrite, barium ferrite, spinel ferrite, and epsilon ferrite is used. From the viewpoint of improving the electromagnetic wave absorption characteristics of the AD film 20 in the 3 to 30 GHz frequency band, it is preferable to use carbonyl iron nanoparticles, M-type strontium ferrite substituted with Co and Ti, and Y-type and Z-type ferroxprana-type barium ferrite as the magnetic material. M-type, Y-type, Z-type, and spinel ferrites usually have their crystal lattices destroyed by mechanical shocks associated with AD film formation, leading to deterioration of their magnetic properties. However, by compounding them with a two-dimensional structural material, the shocks can be mitigated and the deterioration of properties can be prevented. From the viewpoint of improving the electromagnetic wave absorption characteristics of the AD film 20 in the millimeter-wave frequency band of 35 to 220 GHz, it is preferable to use epsilon ferrite with elemental substitutions such as gallium, aluminum, and rhodium as the magnetic material. Furthermore, since it is a multiferromaterial possessing both ferromagnetic and ferroelectric properties, a combined effect can also be expected.

[0019] As the dielectric, at least one compound selected from the group consisting of, for example, barium titanate, bismuth ferrite, corundum-structured oxides represented by alumina, hematite, mica, silica, titania, and fullerene is used. From the viewpoint of improving the electromagnetic wave absorption characteristics of the AD film 20 in the 10-20 GHz frequency band, barium titanate is preferably used as the dielectric. From the viewpoint of improving the electromagnetic wave absorption characteristics of the AD film 20 in the 8-12 GHz frequency band, bismuth ferrite is preferably used as the dielectric, and since it is a multiferromaterial, a combined effect can also be expected. To maximize the eddy current loss of the AD film 20, it is desirable to mix various insulating dielectric nanoparticles to increase the sheet resistance and control the conductivity of the two-dimensional structural material, and in particular, it is desirable from the viewpoint of improving film quality to use fullerene powder, which is an insulating nanocarbon with low density.

[0020] (Manufacturing method) A method for manufacturing a two-dimensional structural composite material, as one embodiment of the present invention, is described below.

[0021] (Film deposition by AD method) In a vacuum, two-dimensional structural material powder and functional material powder, for example, with a particle size in the range of 0.1 to 5 μm (average 0.6 μm), are injected onto the substrate 10 from separate or common nozzles and collide with the substrate 10, thereby performing film deposition by aerosol deposition (AD). This AD method forms an AD film 20 with a desired thickness of 1 to 2000 μm. At this time, a high injection gas velocity is desirable, and it is desirable to increase the gas velocity during film deposition by using light element gases such as helium, supersonic nozzles such as Laval nozzles, or high-temperature gases heated to several hundred degrees Celsius. This contributes to improving the film quality as well as improving crystal defects in the two-dimensional structural material. When depositing a film by mixing two-dimensional structural material powder and functional material powder, it is desirable to perform a composite treatment beforehand by milling or using a high-speed blender. If the bonding strength of the two-dimensional structural material is weak and it is prone to peeling, it is desirable to use an inorganic material binder such as polyvinyl alcohol (PVA) or polyvinyl butyral (PVB). While powder is typically supplied to a vacuum chamber using a shaker, using a table-type powder feeder allows for more stable supply and thus more stable film quality.

[0022] Because two-dimensional structural materials and graphite have reducing properties, when composited as functional nanoparticles with materials whose magnetic properties deteriorate due to oxidation, such as iron, surface oxidation can be reduced by high-temperature heat treatment of 800°C or higher after film formation. However, when composited with ferrite or various dielectric oxides, high-temperature heat treatment after film formation is undesirable because it reduces the constituent pure elements, such as iron, to a degree that degrades the properties.

[0023] (sample)

[0024] (Sample 1) As the two-dimensional structural material powder, graphene powder (two-dimensional structural material, manufactured by Graphene Platform Inc.) was used, having an average particle size d of 0.6 μm, a particle number ratio of 70% or more with 10 or more layers (thickness in the c-axis direction of approximately 3.3 nm or more), and a particle number ratio of 95% or more with 30 or more layers (thickness in the c-axis direction of approximately 10 nm or more). This two-dimensional structural material powder is obtained by delaminating the interlayers of natural graphite through a combined action of mechanical grinding with a jet mill or ball mill and physical energy irradiation with plasma or microwaves.

[0025] As a functional material powder, particle size D 50 Phosphate-coated iron carbonyl (CIP) powder (manufactured by Jiangsu Tianyi Ultrafine Metal Powder) containing particles in the range of 1.8 μm or less was used.

[0026] The mass ratio of the two-dimensional structural material powder to the total mass of the two-dimensional structural material powder and functional material powder in the AD film raw material was adjusted to 20% by mass. A rectangular plate-shaped substrate 10 (manufactured by Toshiba Ceramics Co., Ltd.) measuring 35 × 35 mm × 500 μm thick, made of quartz SiO2, was sprayed with the two-dimensional structural material powder and functional material powder according to the AD method to produce an AD film 20 with a thickness of 116 μm, which served as sample 1. In the AD film 20 (sample 1), the mass ratio of the two-dimensional structural material powder 21 to the total mass of the two-dimensional structural material particles 21 and functional material particles 22 was 90.4% by mass, and the sheet resistance R S The resistance was 0.63Ω.

[0027] The two-dimensional structural material powder and the functional material powder were pre-mixed in a high-speed blender and sealed in a glass shaker container. After the chamber was evacuated using a rotary pump, helium gas was introduced from the shaker into the chamber at a flow rate of 20 L / min, and the gaseous powder stream was blown onto the substrate. The injection nozzle had a 10 mm wide linear outlet, and film deposition was performed by scanning the substrate at a speed of 1 mm / sec.

[0028] Figures 2A and 2B show scanning electron microscope images of the surface of sample 2, respectively. The white spherical objects are carbonyl iron nanoparticles treated with phosphoric acid, while the other black areas are the two-dimensional structural material. From the magnified view of Figure 2B, it can be seen that a portion of the carbonyl iron particles are covered by the translucent two-dimensional structural material. Since c-axis orientation can be confirmed from X-ray diffraction, it is thought that the carbonyl iron particles are embedded between the layers of two-dimensional structural material stacked parallel to the substrate.

[0029] (Sample 2) Except for adjusting the mass ratio of the two-dimensional structural material powder to the total mass of the two-dimensional structural material powder and functional material powder in the AD film raw material to 10% by mass, an AD film 20 with a thickness of 524 μm was fabricated as Sample 2 under the same film formation conditions as Sample 1. In the AD film 20 as Sample 2, the mass ratio of the two-dimensional structural material powder 21 to the total mass of the two-dimensional structural material particles 21 and functional material particles 22 was 90.6% by mass, and the sheet resistance R S The resistance was 0.18Ω.

[0030] (Sample 3) Except for adjusting the mass ratio of the two-dimensional structural material powder to the total mass of the two-dimensional structural material powder and functional material powder in the AD film raw material to 5% by mass, an AD film 20 with a thickness of 24 μm was fabricated as Sample 3 under the same film formation conditions as Sample 1. In the AD film 20 as Sample 3, the mass ratio of the two-dimensional structural material powder 21 to the total mass of the two-dimensional structural material particles 21 and functional material particles 22 was 80.5% by mass, and the sheet resistance R S The resistance was 4.1Ω.

[0031] (Sample 4) As a functional material powder, the particle size is in the range of 3 to 40 μm (D 50 Except for the use of reduced iron powder (manufactured by DOWA-IP Creation Co., Ltd.) contained in a 7μm film, an AD film 20 with a thickness of 2.8μm was fabricated as Sample 4 under the same film formation conditions as Sample 1. In the AD film 20 as Sample 4, the mass ratio of the two-dimensional structural material powder 21 to the total mass of the two-dimensional structural material particles 21 and functional material particles 22 was 96.0 mass%, and the sheet resistance RS was 81.0 Ω.

[0032] (Sample 5) As the functional material powder, Sr ferrite powder (manufactured by DOWA Eftec Co., Ltd.) with an average particle size of 1.18 μm, a specific surface area of 2.17 m 2 / g, and a tap density of 3.22 g / cm 3 was used. Except for this, under the same film formation conditions as in Sample 1, according to the AD method, it was sprayed onto the substrate 10 as a single crystal silicon substrate (supplied by AS ONE Corporation), and an AD film 20 with a film thickness of 950 μm was produced as Sample 5. The mass ratio of the two-dimensional structure material particles 21 to the total mass of the two-dimensional structure material particles 21 and the functional material particles 22 in the AD film 20 as Sample 5 was 87.7 mass%.

[0033] (Sample 6) [[ID=1​​​​​​​​​​​​​​​​​ The Sr ferrite powder used as the functional material powder in the preparation of sample 5 was sprayed onto a silicon single crystal substrate (supplied by AS ONE Corporation) substrate 10 under the same film deposition conditions as reference sample 1, following the AD method, thereby producing an AD film with a thickness of 2.7 μm as reference sample 2.

[0037] (Reference sample 3) The phosphate-coated iron carbonyl (CIP) powder used as a functional material powder in the preparation of Samples 1-3 and the Sr ferrite powder used as a functional material powder in the preparation of Sample 5 were sprayed onto a silicon single crystal substrate (supplied by AS ONE Corporation) 10 under the same deposition conditions as Reference Sample 1, according to the AD method, thereby producing an AD film with a thickness of 2.3 μm as Reference Sample 3. The mass ratio of phosphate-coated iron carbonyl (CIP) powder to Sr ferrite powder in the AD film raw materials was adjusted to 0.8:0.2.

[0038] (X-ray diffraction spectrum) Figures 3A to 3E show the XRD spectra of (1) Sample 1, (2) Sample 2, (3) Sample 3, (4) Sample 4, and (5) Reference Sample 1, respectively. As shown in Figures 3A to 3D, the XRD spectra of Samples 1 to 4 each show (002), (004), and (006) peaks originating from the two-dimensional structural material particles 21, and no peaks originating from other orientations are observed, indicating that in all cases the two-dimensional structural material particles are c-axis oriented. As shown in Figure 3E, the XRD spectrum of Sample 5 shows (002) and (004) peaks originating from the two-dimensional structural material particles 21, and no peaks originating from other orientations are observed, indicating that the two-dimensional structural material particles are c-axis oriented.

[0039] Figures 4A to 4C show the XRD spectra of (1) Reference Sample 1, (2) Reference Sample 2, and (3) Reference Sample 3, respectively. As shown in Figures 4A to 4C, the carbonyl iron AD films used as Reference Samples 1 to 3 show a low-intensity, broad halo only near the (110) orientation, indicating amorphous-like crystalline properties. In the composite AD films of two-dimensional structural materials and functional materials used as Samples 1 to 5, multiple crystalline peaks of iron are clearly observed, suggesting that the crystal lattice fracture is mitigated by the two-dimensional structural material.

[0040] (Magnetization curve) Figures 5A to 5E show the magnetization curves for (1) Sample 1, (2) Sample 2, (3) Sample 3, (4) Sample 4, and (5) Sample 5, respectively. In all cases, a high saturation magnetic field, which is often observed when the particle size is small, is confirmed. Compared to the carbonyl iron-2D structural material composite AD films of Samples 1 to 3, the magnetization of the reduced iron-2D structural material composite AD film of Sample 4 and the carbonyl iron AD film of Reference Sample 1 are one to two orders of magnitude smaller. This is thought to be because Sample 4 lacks a surface protective layer, resulting in the effects of oxidation, and because Reference Sample 1 lacks the shock mitigation effect of the 2D structural material.

[0041] Figures 6A to 6C show the magnetization curves for (1) Reference Sample 1, (2) Reference Sample 2, and (3) Reference Sample 3, respectively. In all cases, a high saturation magnetic field, which is often observed with small particle sizes, is confirmed. Compared to Sample 5, the magnetization of Reference Samples 2 and 3 is about 1 / 25th the size. This is thought to be because Reference Samples 2 and 3 do not have the shock mitigation effect of the two-dimensional structural material.

[0042] (Evaluation of electromagnetic wave attenuation and transmission characteristics) Each sample is fixed on a microstrip line, and a vector network analyzer is used to analyze the near-field P in the frequency range of 10 MHz to 40 GHz. loss / P in Characteristics were measured. Measured (1) Incident quantity P inThe amount of incidence P to the said amount in and the difference P in transmission amount loss Ratio P loss / P in (2) Return loss S 11 and (3) transmission attenuation S 21 The relationship is expressed by the following equation (01), where the reflection and transmission attenuation are small and P is close to 1. loss / P in The more extreme the characteristic, the better it is considered to be.

[0043] P loss / P in =1-(|S 21 | 2 +|S 11 | 2 ) ... (01).

[0044] Figures 7A to 7C each show the frequency dependence (10 MHz to 40 GHz) of the measurement results (1) to (3) for sample 6, along with the measurement results for the substrate alone (dashed line).

[0045] (Effects of the present invention)

[0046] (1. c-axis orientation characteristics) In the present invention, the two-dimensional structural material of the two-dimensional structural material-based composite AD film is c-axis oriented regardless of the combination of functional material powders used in composite formation. Therefore, AD film formation is a favorable manufacturing method for electromagnetic wave absorbing materials, and functional material powders such as carbonyl iron powder, reduced iron powder, Sr ferrite, ε-ferrite, fullerene, alumina, and barium titanate can be applied to enhance electromagnetic wave absorption properties. Due to the unique two-dimensionality of its chemical bonding state, the two-dimensional structural material has extremely high electrical conductivity in the c-plane (ab-plane) compared to the c-axis direction, making it usable as a conductive or electromagnetic wave shielding / absorbing material. At the same time, it also has extremely high thermal conductivity in the c-plane (ab-plane), making it usable as a heat dissipation or heat dispersion sheet. The simultaneous possession of electromagnetic wave absorption / shielding properties and heat dispersion / dissipation properties is advantageous for applications in 5G and 6G mobile communication equipment where heat generation in electronic devices due to increasing data processing volume is a problem. Similar to carbon nanotubes, the two-dimensional structural composite material exhibits a large change in electrical resistance with mechanical deformation, making it applicable as a pressure or strain sensor. Carbon-based materials are advantageous for the above applications because they have a lower density and can be made lighter compared to inorganic materials such as metals and ceramics.

[0047] (2. Impact mitigation characteristics) M-type Ba or Sr ferrites are hard ferrites with high saturation magnetic fields, making them promising as radio wave absorbers in the high-frequency bands of SHF (3-30 GHz) or EHF (30-300 GHz). However, the mechanical shock generated during AD deposition destroys the crystal lattice, significantly degrading magnetic properties such as coercivity and prismaticity. High-temperature heat treatment up to around 1000°C is required to restore these degraded properties, which is disadvantageous when used on flexible sheets with low heat resistance, such as polyimide. Similar effects have been reported with other carbon-based materials, but it is thought that the functional material particles exhibit shock-absorbing properties due to the composite with two-dimensional structural materials. As a result, there is almost no change in the X-ray diffraction pattern and magnetic properties before and after deposition, eliminating the need for post-deposition treatment, which is advantageous for applications.

[0048] (3. Improvement of film quality by compounding with dissimilar materials or modification with functional groups (-COOH,-NH3)) Because the bonds between two-dimensional structural materials are relatively weak van der Waals forces, it is difficult to obtain high-density films using two-dimensional structural materials alone. However, this can be improved by compounding with different materials or by modifying with functional groups such as carbonyl groups (-COOH) or amino groups (-NH3). Furthermore, to reinforce the bonding force between two-dimensional structural materials and functional material particles, powders pre-treated with binders such as polyvinyl alcohol (PVA) can be used as raw materials for AD film formation. Compounding with titania (TiO2) fine particles also makes it possible to apply this to dye-sensitized solar cells.

[0049] (4. Influence of composite magnetic materials or dielectrics on radio wave absorption properties) Since two-dimensional structural materials are conductive materials, eddy current losses are considered to be dominant in the manifestation of radio wave absorption characteristics. However, enhancement of absorption characteristics is expected by combining them with magnetic materials or dielectrics that have absorption in specific frequency bands. Carbonyl iron (f r ~30GHz), Sr ferrite (Co,Ti,Al substitution f r <~80GHz), ε-ferrite (Ga,Al,Rh substitution f r = 35~220GHz), fullerene, alumina, BaTiO3(f r While the filler content in mixed sheets with rubber, etc., is limited to around 30% (for frequencies above 10GHz), AD deposition allows for 100%, improving radio wave absorption characteristics.

[0050] (Application fields of the present invention) The two-dimensional structural composite material according to the present invention may be used as a radio wave absorbing material in the frequency band of 10 to 300 GHz. It can be applied to technical fields such as 5G / 6G mobile communications, intelligent transportation systems (ITS), and wireless LANs. High P in the 10 to 40 GHz band. loss / P inThe present invention possesses the following properties. The two-dimensional structured composite material may be used as a heat dissipation / thermal dispersion material, such as a thermal dispersion sheet for electronic elements inside smartphones. The two-dimensional structured composite material may be used as an electrode material for batteries such as lithium-ion batteries, lithium-air batteries, dye-sensitized solar cells, and supercapacitors. The two-dimensional structured composite material may be used as a stretchable strain sensor, exhibiting a gauge factor of 100-200 similar to that of semiconductors, and as a pressure / strain sensor such as a biological monitor (pulse / blood pressure) and a motion sensor. [Explanation of Symbols]

[0051] 10... Circuit board 20‥AD membrane (two-dimensional structure composite material) 21‥2D structure material particles 22‥Functional material particles.

Claims

1. It is composed of an aerosol deposition film of two-dimensional structural material particles and functional material particles, Two-dimensional structural material particles are stacked to exhibit c-axis orientation. Functional material particles are encapsulated by two-dimensional structural material particles. Two-dimensional structural composite material.

2. In the two-dimensional structural composite material according to claim 1, The mass ratio of two-dimensional structural material particles to the total mass of two-dimensional structural material particles and functional material particles falls within the range of 60 to 99.9% by mass. Two-dimensional structural composite material.

3. A method for manufacturing a two-dimensional structural composite material according to claim 1, The process includes a step of spraying two-dimensional structural material powder and functional material powder onto a substrate according to the aerosol deposition method. A method for manufacturing two-dimensional structural composite materials.

4. In the method for manufacturing a two-dimensional structural composite material according to claim 3, The mass ratio of functional material powder to the total mass of two-dimensional structural material powder and functional material powder falls within the range of 50 to 99.9% by mass. A method for manufacturing two-dimensional structural composite materials.

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