CN113329608B - Preparation method of nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance - Google Patents

Preparation method of nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance Download PDF

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CN113329608B
CN113329608B CN202110736189.0A CN202110736189A CN113329608B CN 113329608 B CN113329608 B CN 113329608B CN 202110736189 A CN202110736189 A CN 202110736189A CN 113329608 B CN113329608 B CN 113329608B
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谢雨希
齐建全
韩鹏
于天池
厉正琴
管彤
孙海波
李煜
李宏峰
韩秀梅
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Northeastern University Qinhuangdao Branch
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Abstract

The invention relates to a preparation method of a high wave-absorbing nano barium titanate/ferroferric oxide hybrid material. The method comprises the step of adding nano Fe into a solution3O4Direct in-situ deposition of particles on nano BaTiO3The surface of the material forms hybrid material powder, nano Fe3O4In nano BaTiO3The surface forms surface contact, a large number of interfaces are generated, and an electromagnetic wave barrier is formed due to the accumulation of a large number of defects and ions on two sides of the interfaces, so that electromagnetic waves of various frequency bands are strongly absorbed and scattered. The hybrid material formed by the powder has high electric loss and magnetic loss. At 20Hz-3GHz, the dielectric constant is 10-1000, and the electric loss is 0.1-44.3; at 10Hz-1GHz, the magnetic conductivity is 3.69-9.5, and the magnetic loss is 6.7-15.9; when the thickness of the hybrid material is 2mm, the reflectivity is-9.84 to-29.4 dB at 2GHz, and the absorptivity is 89.62% -99.89%. Has good electromagnetic wave absorption performance, and is particularly suitable for being used as a wave-absorbing material or an electromagnetic shielding material.

Description

Preparation method of nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance
The technical field is as follows:
the invention belongs to the technical field of wave-absorbing materials and electromagnetic shielding material preparation, and particularly relates to a preparation method of a high-wave-absorbing-performance nano barium titanate/ferroferric oxide hybrid material.
Background art:
the wave-absorbing material is a material which can absorb electromagnetic wave energy projected on the surface of the wave-absorbing material and convert the electromagnetic wave energy into heat energy or other forms of energy through the dielectric loss of the material. Generally, the absorbent is compounded by a matrix material and the absorbent. According to the wave-absorbing mechanism, the wave-absorbing material can be divided into an electric loss type and a magnetic loss type: the electric loss type wave-absorbing material mainly absorbs and attenuates electromagnetic waves through electronic polarization, ionic polarization, interface polarization and the like of a medium; the magnetic loss type wave-absorbing material mainly absorbs and attenuates electromagnetic waves through magnetic excitation mechanisms such as magnetic hysteresis loss, domain wall resonance, after effect loss and the like.
BaTiO3And Fe3O4The coating wave-absorbing material belongs to the traditional coating wave-absorbing material, has the advantages of simple preparation method, low price of raw materials and the like, but also has the defects of narrow absorption band, low absorption strength and the like. BaTiO 23Is a dielectric material, but the wave absorption performance of the unmodified pure barium titanate is not ideal. Fe3O4The ferrite is a magnetic loss material, is a more and more mature wave-absorbing material, and has the advantages of high absorption efficiency, thin coating, wide frequency band and large relative density, so that the weight of the component is increased, the overall performance of the component is influenced, and the high-frequency effect is not ideal. With the rapid development of modern science and technology, traditional materials and single-phase materials cannot meet higher and higher application requirements, and hybrid materials may be an ideal way for solving the problem. The existing preparation method is mainly a traditional mechanical mixing method, so that the particles of various materials are in point-to-point contact, and the contact area is small.
Comprises partially utilizing piezoelectric property and electromagnetic wave absorption property in the prior art to mix BaTiO3And Fe3O4Dispersing the nano particles into PAN solution to obtain BaTiO3/Fe3O4The PAN spinning solution is then subjected to electrostatic spinning, and in order to meet the requirement that electromagnetic shielding can be applied in a large range, the spinning preparation 1 is high in cost and unstable in process, needles are easily blocked during PAN production, the efficiency is low and environment-friendly, and 2. the size is large, particles are not uniformly distributed on the filament, and the efficiency is lowAnd 3, the material prepared by the spinning method needs to be sintered, so that the problems of environmental protection and energy consumption are easily caused.
In addition, in the preparation process of the wave-absorbing material of graphene/ferroferric oxide powder, an ultrasonic dispersion method is utilized to obtain a graphene oxide colloidal solution, and the graphene oxide colloidal solution and the ferroferric oxide powder are mechanically mixed, and the graphene oxide colloidal solution and the ferroferric oxide are in point-to-point contact, so that the contact area is small.
The invention also provides a preparation process of the polyaniline-barium ferrite-graphene electromagnetic shielding material, which comprises the steps of preparing three-dimensional porous graphene oxide by using an ultrasonic dispersion method, then preparing cobalt-titanium co-doped barium ferrite, adding aniline and ammonium persulfate, and then preparing the polyaniline-barium ferrite-graphene electromagnetic shielding material by using a physical ultrasonic dispersion method.
Additionally using FeCl3And FeSO4Preparation of nano Fe by chemical coprecipitation method3O4Particles of Fe prepared by in-situ chemical reaction3O4a/PANI complex system. Preparing nano BaTiO by sol-gel method3Powder of nano Fe3O4With nano BaTiO3The powder is mechanically mixed evenly according to different mass ratios to obtain Fe3O4/BaTiO3The composite system has point-to-point contact between particles.
In addition, the coprecipitation method is adopted to prepare the nano Fe3O4Powder mode, and preparation of nano BaTiO by using sol-gel method3And (2) powder, namely mechanically mixing the two kinds of powder uniformly according to different mass ratios, mixing each ingredient with paraffin according to the mass ratio of 3: 1, heating to melt and uniformly stirring to prepare a required test sample, wherein the two kinds of powder are mechanically mixed, so that particles are in point-to-point contact with each other, and the contact area is small.
The invention content is as follows:
the invention aims to overcome the defects in the prior art and provides a preparation method of a nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance.
The hybrid materialThe advantages of barium titanate and ferroferric oxide are integrated, so that the barium titanate and the ferroferric oxide are not simply superposed, and the two single nano-structure materials are compounded together to form a novel functional hybrid material. The hybrid material is prepared by adding two kinds of nano barium titanate BaTiO3Nano ferroferric oxide Fe3O4In addition to the absorption and scattering of the particles, there is also absorption and scattering at a number of interfaces between the two. The continuity of the ferroferric oxide magnetic medium improves the magnetic performance, so that high magnetic conductivity can be ensured, the magnetic loss can be improved, and the electrical loss is improved after the barium titanate is subjected to hybridization modification. The hybrid material enables nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material has high magnetic permeability, electric loss and magnetic loss.
The hybrid material is of a nano structure, so that the electric loss and the magnetic loss of the material are obviously increased, and the hybrid material has more excellent wave-absorbing performance, thereby realizing practical application such as electromagnetic shielding. In order to improve the wave absorbing performance of the hybrid material, nano Fe3O4Direct in-situ deposition of particles on nano BaTiO3The surface of the material forms hybrid material powder, nano Fe3O4In nano BaTiO3The surfaces are in surface contact, a large number of interfaces are generated, and due to the accumulation of a large number of defects and ions on two sides of the interfaces, an electromagnetic wave barrier is formed, so that the electromagnetic waves of all frequency bands are strongly absorbed and scattered.
Because the optimization function of the dielectric constant and the magnetic conductivity of the material is influenced by the thickness of the material, the thickness can influence the wave-absorbing performance of the wave-absorbing material, and the wave-absorbing performance of the material can be controlled by changing the thickness of the material.
In order to achieve the purpose, the invention adopts the following technical scheme:
the preparation method of the nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance comprises the following steps:
s1 preparation of nano BaTiO by DSS method, ball milling method, Sol-gel method or hydrothermal method3(ii) a Pulverizing, sieving to obtain nanometer BaTiO with particle size of 10-500 nm3Powder;
s2, pressMolar ratio of FeCl2·4H2O:FeCl3·6H2Dissolving the two in a solvent to prepare a Fe source solution;
s3 step S1 of nano BaTiO3Adding a small amount of solvent into the powder, grinding the powder into slurry, and mixing the slurry with NaOH solution to obtain mixed slurry, wherein the nano BaTiO is3The mass ratio of the powder to the NaOH solute is (0.5-2) to 1;
s4, dropwise adding the Fe source solution obtained in the step S2 into the mixed slurry obtained in the step S3 through a burette under the water bath heating condition, and carrying out hybridization reaction, wherein the heating temperature is 60-80 ℃, the heating time is 20-40min, and nano barium titanate/ferroferric oxide hybrid materials are generated, wherein the molar ratio of barium titanate: ferroferric oxide (0.05-0.95) and (0.95-0.05);
s5, washing and drying the hybrid material to obtain the nano barium titanate/ferroferric oxide (BaTiO) with high wave absorption performance3/Fe3O4) The nano barium titanate/ferroferric oxide (BaTiO) powder of the hybrid material3/Fe3O4) The hybrid material comprises BaTiO3Phase and magnetic Fe3O4Phase of said nano Fe3O4Particles directly deposited on nano BaTiO3Forming hybrid material powder on the surface, depositing on the nano BaTiO3Nano Fe of surface3O4The particle size is tiny, the two are in face-to-face contact, the contact area is large, and the distribution is uniform and compact.
The step S1 is to obtain the nano BaTiO when the Sol-gel method or the hydrothermal method is adopted3The powder needs to be refluxed in 0.01-0.1mol/L barium hydroxide solution for 10-14h to hydroxylate the powder. The nano BaTiO3Hydroxylating to obtain nano BaTiO3The surface generates oxyhydrogen bonds to realize nano Fe3O4Better in-situ deposition on nano BaTiO3A surface.
In the step S1, when the DSS method is adopted, the specific preparation process is as follows:
1. 31.544g of barium hydroxide octahydrate is added into 100g of water, a beaker is sealed by a preservative film, and the beaker is placed into a magnetic stirrer at room temperature, wherein the magnetic stirrer is set to be at 80 ℃ and 7 rpm;
2. after the temperature of the magnetic stirrer reaches 80 ℃, 100ml of absolute ethyl alcohol is poured, and then a preservative film is sealed;
3. pouring 80ml of absolute ethyl alcohol into another beaker, pouring 34.032g of tetrabutyl titanate into 80ml of absolute ethyl alcohol, rinsing the tetrabutyl titanate beaker by using 20ml of absolute ethyl alcohol, and pouring the rinsed tetrabutyl titanate beaker into the absolute ethyl alcohol beaker together;
4. pouring the solution 3 into a transfusion tube after the solution is prepared, adjusting the dropping speed by using a roller after an isomagnetic stirrer is stabilized at 80 ℃ for ten minutes, and dropping the solution 3 into a beaker 2 dropwise;
5. after the solution 3 is completely dripped, keeping the temperature of 80 ℃ and the rpm of 7 unchanged, and aging the mixed solution for 3 hours;
6. and after 3 hours of aging, pouring out the supernatant, putting the beaker into an oven, drying, fully grinding, and bagging for later use.
In the step S1, when the ball milling method is adopted, the specific preparation process is as follows: a general reaction of Ba (OH)2·8H2O, Anhydrous ethanol and Ti (OBu)4Mixing, ball milling in a ball milling tank for 1-20 hr to obtain nanometer BaTiO3Wherein, in volume ratio, Ba (OH)2·8H2O: absolute ethyl alcohol ═ (0.001-9.999): (9.999-0.001), Ba (OH)2·8H2O:Ti(OBu)4=(0.05-0.95):(0.95-0.05)。
In the step S1, nanometer BaTiO3After the powder is subjected to sintering heat treatment operation, grinding the powder into slurry in the subsequent step S3, wherein the sintering temperature is 300-800 ℃, the heat preservation time is 2-4h, the sintering is carried out in a muffle furnace, and specifically, the nano BaTiO is3Pressing the powder into a briquette, sintering, cooling along with the furnace to obtain the heat-treated BaTiO3And (3) powder blocks.
In the step S1, the sintering temperature is preferably 550-.
In the steps S2 and S3, the solvent is one or a mixture of several of methanol, ethanol, water, hexane, carbon tetrachloride, benzene, toluene, xylene, diethyl ether, acetic acid, formaldehyde or acetone.
In step S2, to avoid FeCl2·4H2The O is dissolved and is not subjected to air oxidation for a long time, and FeCl is dissolved firstly3·6H2O, FeCl to be added2·4H2O immediately followed the experiment.
In the step S3, the mass concentration of the NaOH solution is 2-3 g/ml.
In step S4, the heating method is water bath heating.
The nano barium titanate/ferroferric oxide (BaTiO) obtained in the step S43/Fe3O4) Hybrid material powder by changing hybrid ratio and BaTiO3The heat treatment process of the nano powder and a proper forming method can obtain the hybrid materials with different dielectric constants, electric losses, magnetic conductivities, magnetic losses and hysteresis loops.
In the step S4, the prepared hybrid material powder is formed into a sheet, electrodes are introduced into two surfaces of the sheet, and performance detection is performed, the nano hybrid material formed by the hybrid material powder has very high electric loss and magnetic loss, the dielectric constant can reach 10-1000 and the electric loss can reach 0.1-44.3 at 20Hz-3 GHz; the magnetic conductivity can reach 3.69-9.5 and the magnetic loss can reach 6.7-15.9 at 10Hz-1 GHz; when the thickness of the hybrid material is 2mm, the reflectivity can reach-9.84 to-29.4 dB at 2GHz, and the absorptivity can reach 89.62-99.89%.
In the step S4, preferably, the reflectivity of the hybrid material at 2GHz can reach-12.7 to-29.4 dB, and the absorptivity can reach 92.76% -99.89%.
And after the thickness D and the diameter l of the round ceramic sample are measured by a micrometer, the dielectric constant epsilon and the dielectric loss D of the round ceramic sample are measured by an impedance analyzer.
The electrode introduction mode comprises methods such as pressing, evaporation or silver paste coating, and the like, wherein:
when the pressing method is adopted, the concrete process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is placed between two layers of aluminum foils, and is pressed into a required sheet by 1-100MPa pressure for 0.5-20min, wherein the aluminum foils are used as electrode materials.
When the evaporation method is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is pressed into a required sheet by 1-300MPa pressure, and then metal electrodes are formed on the two sides of the sheet by methods such as vapor deposition and the like.
When the silver coating slurry method is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is used as an electrode by using a screen printing process and then sintered at a high temperature of 500-1300 ℃.
The hybrid material powder molding mode is injection molding, dry pressing molding, tape casting molding, isostatic pressing molding, hot die casting molding or extrusion molding and the like, wherein:
when injection molding is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is pressed, injected, cooled, separated and the like to manufacture a semi-finished product with a certain shape.
When dry pressing molding is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is added with a small amount of adhesive for granulation, then put into a die, and pressurized on a press machine, so that the powder particles are close to each other in the die and firmly combined by internal friction force to form a blank with a certain shape.
When the tape casting is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The method comprises the steps of crushing the hybrid material, mixing the crushed hybrid material with an organic plasticizer solution according to a proper proportion to prepare slurry with a certain viscosity, enabling the slurry to flow down from a container, scraping and coating the slurry on a special base belt by a scraper with a certain thickness, drying and curing the slurry, peeling the dried and cured slurry to form a film of a green belt, punching, laminating and other processing treatments on the green belt according to the size and shape of a finished product, and preparing a blank to be sinteredAnd (5) finishing.
When isostatic pressing is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is placed in a high-pressure container, and the sample is uniformly pressurized from all directions by utilizing the incompressible property and the uniform pressure transmission property of the liquid medium, so that the powder is formed into a compact blank.
When hot-press casting molding is adopted, the specific process is as follows: under the action of pressure, melting wax-containing nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material is filled in a metal mold, cooled and solidified in the mold, and then demolded.
When extrusion molding is adopted, the specific process is as follows: mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) And (3) extruding the hybrid material by using a hydraulic press to extrude the hybrid material from the die in the non-rubber extruder processing. The extruder is heated and plasticized by the barrel and the screw, and the mixture is pushed forwards by the screw while continuously passing through the machine head to be manufactured into products or semi-products with various sections.
The nano barium titanate/ferroferric oxide hybrid material powder with high wave absorption performance is used for preparing wave-absorbing paint or electromagnetic shielding material.
The invention has the beneficial effects that:
the invention relates to a preparation method of a high wave-absorbing nano barium titanate/ferroferric oxide hybrid material, which is characterized in that nano Fe is in solution3O4Direct in-situ deposition of particles on nano BaTiO3The surface of the material forms hybrid material powder, nano Fe3O4In nano BaTiO3The surfaces are in surface contact, a large number of interfaces are generated, and due to the accumulation of a large number of defects and ions on two sides of the interfaces, an electromagnetic wave barrier is formed, so that the electromagnetic waves of all frequency bands are strongly absorbed and scattered. The wave-absorbing material has the following basic characteristics: when the electromagnetic wave is transmitted and incident to the surface of the wave-absorbing material, the electromagnetic wave can enter the wave-absorbing material to the maximum extent so as to reduce the direct reflection of the electromagnetic wave. Secondly, once the electromagnetic wave enters the material, the wave-absorbing material can absorb the incident electromagnetic waveThe wave energy is effectively absorbed or attenuated, i.e., electromagnetic losses are generated, and the electromagnetic wave energy is converted into heat energy or other forms of energy, so that the electromagnetic waves are maximally absorbed in the medium.
The hybrid material formed by the prepared hybrid material powder has very high electric loss and magnetic loss. The synthetic process is green and environment-friendly, the raw materials are nontoxic and have no side effect, the biocompatibility is good, the cost is greatly reduced, the method is suitable for industrial production, and the obtained material powder is low in cost, high in performance and high in electric loss and magnetic loss. And the method has wide practical application, can be widely applied to the fields of electronic instruments, finance, commerce, environmental protection and the like, and can be used for making compatibility measures for various electronic products and equipment. The electromagnetic protection is carried out in the area (such as the vicinity of a high-voltage line and a signal tower) with the electromagnetic radiation intensity exceeding the standard, and the electromagnetic protection can also be used for absorbing the electromagnetic radiation at the moment of opening large-scale electric equipment, so that the electromagnetic interference of a computer center machine room is prevented, and the like. In the preparation of nano BaTiO3If the DSS method is adopted to prepare the nano BaTiO3Nano BaTiO obtained by other methods without hydroxylation3The powder is required to be refluxed in 0.01-0.1mol/L barium hydroxide solution for 12 hours to be hydroxylated. Nano BaTiO3Hydroxylation can be carried out on nano BaTiO3The surface generates oxyhydrogen bonds to lead the nano Fe3O4Better in-situ deposition on nano BaTiO3A surface.
The hybrid material is prepared by adding two kinds of nano barium titanate BaTiO3Nano ferroferric oxide Fe3O4Besides the absorption and scattering of the particles, a large number of interfaces between the particles absorb and scatter, so that the absorption performance of the electromagnetic waves can be greatly enhanced.
The invention relates to nano barium titanate/ferroferric oxide (BaTiO) with high wave absorption performance3/Fe3O4) Preparation and application of hybrid material. It is characterized in that the nano Fe is in solution3O4Direct in-situ deposition of particles on nano BaTiO3The surface of the material forms hybrid material powder, nano Fe3O4In nano BaTiO3The surfaces are in surface contact, a large number of interfaces are generated, and electricity is formed due to the accumulation of a large number of defects and ions on both sides of the interfacesAnd the magnetic wave is shielded, so that the electromagnetic waves of all frequency bands are strongly absorbed and scattered.
Description of the drawings:
FIG. 1 examples 1 and 2 and other examples of nano BaTiO prepared at different raw material ratios3/Fe3O4The low-frequency relative dielectric constant and the low-frequency dielectric loss chart of the hybrid material powder;
FIG. 2 examples 1 and 2 and other examples of nano BaTiO prepared at different raw material ratios3/Fe3O4A low frequency dielectric loss plot of the hybrid material powder;
FIG. 3 examples 3 and 4 and other examples of nano BaTiO prepared with different raw material ratios3/Fe3O4The low-frequency relative dielectric constant and the low-frequency dielectric loss chart of the hybrid material powder;
FIG. 4 examples 3 and 4 and other examples of nano BaTiO prepared at different sintering temperatures3/Fe3O4A low frequency dielectric loss plot of the hybrid material powder;
FIG. 5 example 5 ball milling preparation of nano BaTiO3/Fe3O4A low frequency dielectric loss plot of the hybrid material powder;
FIG. 6 nanometer BaTiO prepared in example 13/Fe3O4High-frequency dielectric constant, electric loss and electric loss angle diagram of the hybrid material powder;
FIG. 7 nanometer BaTiO prepared in example 33/Fe3O4High-frequency dielectric constant, electric loss and electric loss angle diagram of the hybrid material powder;
FIG. 8 nanometer BaTiO prepared in example 13/Fe3O4Low-frequency magnetic conductivity and magnetic loss diagram of the hybrid material powder;
FIG. 9 nanometer BaTiO prepared in example 33/Fe3O4Low-frequency magnetic conductivity and magnetic loss diagram of the hybrid material powder;
FIG. 10 nanometer BaTiO prepared in example 13/Fe3O4The magnetic conductivity, magnetic loss and magnetic loss angle of the hybrid material powder at 10Hz-1GHz are shown;
FIG. 11 prepared in examples 1 and 3Nano BaTiO3/Fe3O4Magnetic hysteresis of the hybrid material powder;
FIG. 12 nanometer BaTiO prepared in examples 1 and 2 and other different raw material ratios3/Fe3O4XRD pattern of the hybrid material powder;
FIG. 13 nanometer BaTiO prepared in example 13/Fe3O4SEM image of the hybrid material powder under 5 ten thousand times;
FIG. 14 nanometer BaTiO prepared in example 23/Fe3O4SEM image of the hybrid material powder under 5 ten thousand times;
FIG. 15 nanometer BaTiO prepared in example 33/Fe3O4SEM image of the hybrid material powder under 5 ten thousand times;
FIG. 16 nanometer BaTiO prepared in example 43/Fe3O4SEM image of the hybrid material powder under 5 ten thousand times.
The specific implementation mode is as follows:
the present invention will be described in further detail with reference to examples.
The absorption of electromagnetic waves depends substantially on whether the wave impedances of the absorber and the air medium are matched. Because only the wave impedance of the two is matched, the electromagnetic wave can be incident into the absorber and can not be reflected greatly; when the electromagnetic wave has a wave impedance of ROIs incident on a dielectric or magnetic surface with an infinite wave impedance Zin, partial reflection will occur.
Calculating the reflectivity of the material by adopting an absorption screen theoretical formula according to the obtained electromagnetic parameters
Figure BDA0003140202320000071
Wherein: zinIs a normalized input impedance, which can be obtained by
Figure BDA0003140202320000072
In the formula: epsilonr=ε′-jε″,μrμ' -j μ ″; j is the imaginary unit; d is the thickness of the sample; f is the frequency; and c is the speed of light.
When Z isinWhen 1, the material is close to full absorption. The absorption properties of the material are thus determined by epsilon ', epsilon ", mu', mu", d and f impedance matching parameters.
For the purpose of better explaining the present invention and to facilitate understanding, the present invention will be described in detail by way of specific embodiments with reference to the accompanying drawings.
Example 1
Weighing 4.0g of NaOH and putting the NaOH into a beaker, then adding 10ml of water, and adding 10ml of absolute ethyl alcohol after the NaOH is dissolved in the water. 2.3319g of nano BaTiO3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. The XRD is as shown in figure 12 (BaTiO)3:Fe3O41: 1). It can be seen that in XRD of the composite material powder, XRD diffraction peaks of two ferroelectrics exist simultaneously, and a sharp small peak appearing at about 32-degree position is BaTiO3The crystal plane is (101); the small peak appearing at about the 34 degree position is Fe3O4The crystal plane of the main peak of (1) is (311). Due to BaTiO3Strong peak, making Fe3O4The peak was not evident, but the peak intensity was evident from software Jade. According to XRD spectrum, the sharp small peak appearing at about 24 degrees is BaCO3hetero-Peak to prepare titrated BaTiO3Carbonization products are produced. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer. The dielectric properties of the sample of this example were analyzed by frequency spectroscopy as shown in FIG. 1 (BaTiO)3:Fe3O41:1), fig. 2 (BaTiO)3:Fe3O41:1), as shown in fig. 6. It can be seen that when BaTiO3And Fe3O4When the materials are compounded at 70 ℃ in a ratio of 1:1, the dielectric constant can reach 241.5 to the maximum at 20Hz-2MHz, and the electric loss can reach 40.7 to the maximum; at 2MHz-3GHz, the dielectric constant can reach 14.1 at most, and the electric loss can reach 0.1363 at most.
The VSM hysteresis loop analysis of the sample of this example shows that the initial permeability is 1.000518 by obtaining the initial magnetization curve as shown in fig. 11 (room temperature). The low-frequency relative permittivity and the low-frequency dielectric loss chart of the sample of this example are shown in FIG. 1, the high-frequency permittivity, electrical loss, and electrical loss angle chart are shown in FIG. 6, the low-frequency permeability and magnetic loss chart are shown in FIG. 8, and the permeability, magnetic loss, and magnetic loss angle at 10Hz-1GHz are shown in FIG. 10. It can be seen that the maximum magnetic conductivity can reach 6.7 and the maximum magnetic loss can reach 13.6 when the frequency is 10kHz-100 kHz; the maximum magnetic conductivity can reach 7.9 and the maximum magnetic loss can reach 14.0 at 10Hz-1 GHz. The XRD pattern of the sample is shown in FIG. 12, and the SEM pattern at 5 ten thousand times is shown in FIG. 13;
when the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-19.6 dB, and the absorptivity can reach 98.9%.
The hybrid material is prepared by adding two kinds of nano barium titanate BaTiO3Nano ferroferric oxide Fe3O4In addition to the absorption and scattering of the particles, there is also absorption and scattering at a number of interfaces between the two. From the analysis of dielectric loss and magnetic loss, the hybrid material can be used for high-performance wave-absorbing materials and electromagnetic shielding materials.
Wherein, the raw material used in the examples 1-4 is nano BaTiO3The powder is obtained at room temperature by adopting a solution direct synthesis method, and the specific preparation process comprises the following steps:
1. 31.544g of barium hydroxide octahydrate is added into 100g of water, a beaker is sealed by a preservative film, and the beaker is placed into a magnetic stirrer at room temperature, wherein the magnetic stirrer is set to be at 80 ℃ and 7 rpm;
2. after the temperature of the magnetic stirrer reaches 80 ℃, 100ml of absolute ethyl alcohol is poured, and then a preservative film is sealed;
3. pouring 80ml of absolute ethyl alcohol into another beaker, pouring 34.032g of tetrabutyl titanate into 80ml of absolute ethyl alcohol, rinsing the tetrabutyl titanate beaker by using 20ml of absolute ethyl alcohol, and pouring the rinsed tetrabutyl titanate beaker into the absolute ethyl alcohol beaker together;
4. pouring the solution 3 into a transfusion tube after the solution is prepared, adjusting the dropping speed by using a roller after an isomagnetic stirrer is stabilized at 80 ℃ for ten minutes, and dropping the solution 3 into a beaker 2 dropwise;
5. after the solution 3 is completely dripped, keeping the temperature of 80 ℃ and the rpm of 7 unchanged, and aging the mixed solution for 3 hours;
6. after 3 hours of aging, pouring out the supernatant, putting the beaker into an oven, drying and fully grinding to obtain the hydroxylated nano BaTiO3And (6) assembling.
The method makes nano BaTiO3Hydroxylation on nano BaTiO3The surface generates oxyhydrogen bond to enable the nano Fe3O4Better in-situ deposition on nano BaTiO3Surface, and BaTiO3The grain diameter can reach 10-15 nm.
The magnetic stirrer in example 1 was turned on only with the heating switch, the rotational speed was adjusted to 0rmp, and an electric stirrer was used above.
Example 2
The used nano BaTiO3The powder was prepared as in example 1 by first synthesizing the solution directly to obtain nano-BaTiO3And (3) powder. Weighing 4.0g of NaOH and putting the NaOH into a beaker, then adding 10ml of water, and adding 10ml of absolute ethyl alcohol after the NaOH is dissolved in the water. 4.6638g of nano BaTiO3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9981g of FeCl2·4H2O and 2.7030gFeCl3·6H2O in 60ml of absolute ethanol, adding the solution to a burette, and droppingAdding the mixture into the emulsion dropwise through a fixed pipe, and stirring continuously. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer. An SEM image of the sample of this example at 5 ten thousand times is shown in FIG. 14; the low frequency relative permittivity and low frequency dielectric loss plot of this example is shown in FIG. 1 (BaTiO)3:Fe3O4As shown in 2:1), in addition to example 1, in other raw material ratios, including BaTiO3/Fe3O4Preparation of hetero ═ 2:3, 3:2 and 2:1 ratios, nano BaTiO prepared in examples 1, 2 and other different raw material ratios3/Fe3O4The low frequency dielectric loss plot of the hybrid material powder is shown in fig. 2.
It can be seen that when BaTiO3And Fe3O4When the composite material is compounded at 70 ℃ in a ratio of 2:1, the dielectric constant can reach 124.9 to the maximum at 20Hz to 2MHz, and the electric loss can reach 23.5 to the maximum. From the data analysis, BaTiO3And Fe3O4When compounded at 70 ℃ in a ratio of 2:1, the ratio of BaTiO to BaTiO3And Fe3O4The dielectric loss of the composite material is low at 70 ℃ in a ratio of 1: 1. The magnetic permeability of the sample in the embodiment can reach 4.4 at maximum in 10kHz-100kHz, and the magnetic loss can reach 11.7 at maximum. The XRD pattern of this sample is shown in fig. 12. An SEM image of the sample at 5 ten thousand magnification is shown in FIG. 14.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-12.7 dB, and the absorptivity can reach 94.6%.
Example 3
The used nano BaTiO3The powder was prepared as in example 1 by first synthesizing the solution directly to obtain nano-BaTiO3Presintering the powder at 550 ℃ for 2 hours, and as can be seen from figure 4, presintering to nano BaTiO with different temperatures3The dielectric loss of the powder is highest at 550 ℃. Weighing 4.0g of NaOH and putting the NaOH into a beaker, then adding 10ml of water, and adding 10ml of absolute ethyl alcohol after the NaOH is dissolved in the water. Then 2.3319g of nano BaTiO with the temperature of 550 ℃ is pre-sintered3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer. The low frequency relative permittivity and dielectric loss profile of the sample of this example are shown in FIG. 3 (BaTiO)3-550 ℃); on the basis of the embodiment 3, the nano BaTiO prepared under the conditions of 500 ℃, 650 ℃ and 700 ℃ and the embodiments 3 and 4 and other different sintering temperatures are respectively selected at other sintering temperatures3/Fe3O4The low-frequency dielectric loss graph of the hybrid material powder is shown in FIG. 4; the high-frequency dielectric constant, electrical loss, and electrical loss angle are shown in fig. 7.
It can be seen that when BaTiO3Pre-burning to 550 ℃, and then compounding at 70 ℃ according to the proportion of 1:1, wherein the dielectric constant can reach 1000 to the maximum at 20Hz-2MHz, and the electric loss can reach 22.6 to the maximum; the dielectric constant can reach 12.6 at most and the electric loss can reach 0.1726 at most when the frequency is 2MHz-3 GHz.
The VSM hysteresis loop analysis of the sample of this example is shown in FIG. 11(550 ℃ C.), and the initial permeability is 1.000430 by obtaining the initial magnetization curve. The low-frequency permeability and magnetic loss graph of the sample is shown in FIG. 9, and it can be seen that the maximum permeability can reach 7.8 and the maximum magnetic loss can reach 14.8 at 10kHz-100 kHz. The maximum magnetic conductivity can reach 9.5 and the maximum magnetic loss can reach 15.9 at 10Hz-1 GHz. An SEM image of the sample at 5 ten thousand magnification is shown in FIG. 15.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-29.4 dB, and the absorptivity can reach 99.89%.
Example 4
The used nano BaTiO3The powder was prepared as in example 1 by first synthesizing the solution directly to obtain nano-BaTiO3The powder was pre-sintered at 600 ℃ for 2 hours. Weighing 4.0g of NaOH and putting the NaOH into a beaker, then adding 10ml of water, and adding 10ml of absolute ethyl alcohol after the NaOH is dissolved in the water. Then 2.3319g of nano BaTiO which is pre-sintered to 600 DEG C3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer. The low frequency relative permittivity and dielectric loss profile of the sample of this example are shown in FIG. 3 (BaTiO)3-600 ℃); on the basis of the example 3, other sintering temperatures are respectively selected to be 500 ℃, 650 ℃ and 700 ℃, and the examples3. 4 nano BaTiO prepared at different sintering temperatures3/Fe3O4The low-frequency dielectric loss graph of the hybrid material powder is shown in FIG. 4; an SEM image of the sample at 5 ten thousand magnification is shown in FIG. 16.
It can be seen that when BaTiO3After pre-burning to 600 ℃, when the composition is carried out at 70 ℃ according to the proportion of 1:1, the dielectric constant can reach 750.9 to the maximum at 20Hz-2MHz, and the electric loss can reach 16.9 to the maximum. From data analysis, BaTiO presintered to 600 deg.C3And Fe3O4BaTiO prepared at 70 ℃ in a ratio of 1:1 and pre-sintered to 550 DEG C3And Fe3O4The dielectric loss is low when prepared at 70 ℃ in a ratio of 1: 1. The magnetic permeability of the sample in the embodiment can reach 6.9 at maximum at 10kHz-100kHz, and the magnetic loss can reach 13.566 at maximum.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-9.84 dB, and the absorptivity can reach 89.62%.
It can be seen from the scanning electron microscope combining the above-mentioned FIGS. 13-16 that the nano BaTiO prepared by the present application3/Fe3O4The hybrid material has the advantages of uniform powder, small particle size and small agglomeration, and is visible in face-to-face contact.
Example 5
Weighing 4.0g of NaOH and putting the NaOH into a beaker, then adding 10ml of water, and adding 10ml of absolute ethyl alcohol after the NaOH is dissolved in the water. Then 2.3319g of ball-milled nano BaTiO3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer. The low frequency dielectric loss plot for the sample of this example is shown in fig. 5 (ball mill).
It can be seen that when BaTiO3And Fe3O4When the composite material is compounded at 70 ℃ in a ratio of 1:1, the dielectric constant can reach 152.5 to the maximum at 20Hz-2MHz, and the electric loss can reach 44.3 to the maximum. The magnetic permeability of the sample in the embodiment can reach 6.18 at maximum in 10kHz-100kHz, and the magnetic loss can reach 12.64 at maximum.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-16.7 dB, and the absorptivity can reach 97.86%.
From the analysis of dielectric loss and magnetic loss, the nano hybrid material can be used for high-performance wave-absorbing materials and electromagnetic shielding materials.
Among them, BaTiO as a raw material used in this example3Is prepared from Ba (OH)2·8H2O, Anhydrous ethanol and Ti (OBu)4Mixing, and ball milling for 1-20h in a ball milling tank. Wherein Ba (OH)2·8H2The volume ratio of O to absolute ethyl alcohol is 1:1, Ba (OH)2·8H2O and Ti (OBu)4In a ratio of 0.5: 0.5. The preparation process comprises the following steps:
1. 0.1mol 31.546g of Ba (OH)2·8H2O and 50ml of absolute ethyl alcohol were mixed and put into a ball mill pot to ball mill for 6 hours to mix Ba (OH)2·8H2Ball milling to nanometer level, wherein the weight of the ball milling beads is 131.4g (the weight of the balls is related to the ball milling efficiency);
2. 0.1mol (34.032g) of Ti (OBu)4Pouring into 50ml of absolute ethyl alcohol (attention is paid to pouring sequence), uniformly stirring, putting into alkaline slurry of a ball milling pot in the first step, and carrying out ball milling for 18h to mix Ba (OH)2·8H2O and Ti (OBu)4And (4) uniformly mixing.
3. The resulting white slurry was poured into a large beaker and dried in a drying oven (temperature set at 70 ℃).
4. And drying and blocking the BT to obtain BT, and fully grinding the BT to obtain the ball-milled barium titanate.
Example 6
The used nano BaTiO3The powder was prepared as in example 5 by weighing 4.0g NaOH and placing in a beaker, then adding 10ml water first, and after dissolving the NaOH in the water, adding 10ml absolute ethanol. Then 4.6638g of ball-milled nano BaTiO3The powder is ground into slurry by adding absolute ethyl alcohol, then poured into the beaker, and then 100ml of absolute ethyl alcohol is added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer.
It can be seen that when BaTiO3And Fe3O4When the composite material is compounded at 70 ℃ in a ratio of 2:1, the dielectric constant can reach 106.2 at most and the electric loss can reach 25.53 at most at 20Hz-2 MHz. The magnetic permeability of the sample in the embodiment can reach 3.69 at maximum at 10kHz-100kHz, and the magnetic loss can reach 6.71 at maximum.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-11.4 dB, and the absorptivity can reach 92.76%.
Example 7
The used nano BaTiO3The powder was prepared as in example 5 by weighing 4.0g NaOH and placing in a beaker, then adding 10ml water first, and after dissolving the NaOH in the water, adding 10ml absolute ethanol. Then 2.3319g of ball-milled nano BaTiO with the temperature of 550 ℃ is pre-sintered3Adding anhydrous powderThe slurry was milled with ethanol and poured into the beaker, and 100ml of absolute ethanol was added. The beaker was placed in a magnetic stirrer and the temperature was set at 70 ℃. 1.9881g of FeCl2·4H2O and 2.7030g FeCl3·6H2Dissolving O in 60ml of absolute ethyl alcohol, adding the solution into a burette, and adding the solution into the emulsion dropwise through the burette with continuous stirring. After the solution is completely added, standing, layering, pouring out the supernatant, adding water, standing, pouring out the supernatant again, and repeating the step for three times (standing at room temperature for layering without aging). And after the mixture is subjected to suction filtration for five times, the mixture is placed into a drying oven with the temperature of 60 ℃ for drying for 24 hours, and brick red hybrid material powder is obtained. Mixing the nano barium titanate/ferroferric oxide (BaTiO)3/Fe3O4) The hybrid material powder is placed between two layers of aluminum foils, the required thin sheet is pressed at normal temperature by using 2MPa pressure, wherein the aluminum foils are used as electrode materials, and the dielectric constant epsilon and the dielectric loss D of the circular ceramic sample wafer are tested by using an impedance analyzer.
It can be seen that BaTiO is ground when being ball milled3After pre-burning to 550 ℃, when the composition is carried out at 70 ℃ according to the proportion of 1:1, the dielectric constant can reach 116.2 to the maximum at 20Hz-2MHz, and the electric loss can reach 21.5 to the maximum. The magnetic permeability of the sample in the embodiment can reach 8.0 at the maximum between 10kHz and 100kHz, and the magnetic loss can reach 10.2 at the maximum.
When the thickness of the material is 2mm, the reflectivity of the material at 2GHz can reach-25.7 dB, and the absorptivity can reach 99.73%.
The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in other forms, and any person skilled in the art can change or modify the technical content disclosed above into an equivalent embodiment with equivalent changes. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention will still fall within the protection scope of the technical solution of the present invention.

Claims (8)

1. The preparation method of the high wave-absorbing nano barium titanate/ferroferric oxide hybrid material is characterized by comprising the following steps:
s1, preparing nano BaTiO by DSS method3(ii) a Pulverizing, sieving to obtain nanometer BaTiO with particle size of 10-500 nm3Powder;
s2, FeCl in molar ratio2·4H2O:FeCl3·6H2O =1 (1-3), dissolving the two in a solvent to prepare a Fe source solution;
s3 step S1 of nano BaTiO3Adding a solvent into the powder, grinding the powder into slurry, and mixing the slurry with a NaOH solution to obtain mixed slurry, wherein the nano BaTiO3The mass ratio of the powder to the NaOH solute is (0.5-2) to 1;
s4, dropwise adding the Fe source solution obtained in the step S2 into the mixed slurry obtained in the step S3 through a burette under the water bath heating condition, and carrying out hybridization reaction, wherein the heating temperature is 60-80 ℃, the heating time is 20-40min, and nano barium titanate/ferroferric oxide hybrid materials are generated, wherein the molar ratio of barium titanate: ferroferric oxide (= (0.05-0.95): 0.95-0.05);
s5, washing and drying the hybrid material to obtain high wave-absorbing nano barium titanate/ferroferric oxide hybrid material powder, wherein the nano barium titanate/ferroferric oxide hybrid material comprises BaTiO3Phase and magnetic Fe3O4Phase, directly depositing nano ferroferric oxide particles on the surface of nano barium titanate to form hybrid material powder, and enabling nano BaTiO to be in a DSS (dye-sensitized solar cell) method3Hydroxylation on nano BaTiO3The surface generates oxyhydrogen bonds to lead the nano Fe3O4In-situ deposition on nano BaTiO3A surface.
2. The preparation method of the high wave-absorbing nano barium titanate/ferroferric oxide hybrid material according to claim 1, wherein in the step S1, nano BaTiO is added3After the powder is subjected to sintering heat treatment operation, grinding into slurry in the subsequent step S3, wherein the sintering temperature is 300-3Pressing the powder into a compact, sintering, cooling along with the furnace to obtainBaTiO after heat treatment3And (3) powder.
3. The preparation method of the high wave-absorbing nano barium titanate/ferroferric oxide hybrid material according to claim 2, wherein in the step S1, the sintering temperature is 550-600 ℃, and the heat preservation time is 2-3 h.
4. The method for preparing a high wave-absorbing nano barium titanate/ferroferric oxide hybrid material according to claim 1, wherein in step S2 or S3, the solvent is one or more of methanol, ethanol, water, hexane, carbon tetrachloride, benzene, toluene, xylene, ether, acetic acid, formaldehyde or acetone.
5. The preparation method of the high wave-absorbing nano barium titanate/ferroferric oxide hybrid material according to claim 1, wherein in the step S3, the mass concentration of NaOH solution is 2-3 g/ml.
6. The method for preparing nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance according to claim 1, wherein in step S4, the prepared hybrid material powder is formed into a sheet, electrodes are introduced on both sides for performance detection, and the nano hybrid material formed by the hybrid material powder has a dielectric constant of 10-1000 and an electrical loss of 0.1-44.3 at 20Hz-3 GHz; at 10Hz-1GHz, the magnetic conductivity is 3.69-9.5, and the magnetic loss is 6.7-15.9; when the thickness of the hybrid material is 2mm, the reflectivity is-9.84 to-29.4 dB at 2GHz, and the absorptivity is 89.62-99.89%.
7. The preparation method of the high wave-absorbing nano barium titanate/ferroferric oxide hybrid material according to claim 6, wherein in the step S4, the reflectivity of the nano hybrid material after the hybrid material powder is molded is-12.7 to-29.4 dB at 2GHz, and the absorptivity is 92.76 to 99.89 percent.
8. The nano barium titanate/ferroferric oxide hybrid material with high wave-absorbing performance prepared by the method of claim 1 is characterized by being used for preparing wave-absorbing coating or electromagnetic shielding material.
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CN109095919A (en) * 2018-08-01 2018-12-28 浙江大学 A kind of barium titanate/cobaltosic oxide complex phase millimeter wave wave-absorbing powder and preparation method with multistage microstructural distribution

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