CN112174217A - Carbon-coated magnetic ferroferric oxide hollow sphere material and preparation method and application thereof - Google Patents
Carbon-coated magnetic ferroferric oxide hollow sphere material and preparation method and application thereof Download PDFInfo
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- SZVJSHCCFOBDDC-UHFFFAOYSA-N ferrosoferric oxide Chemical compound O=[Fe]O[Fe]O[Fe]=O SZVJSHCCFOBDDC-UHFFFAOYSA-N 0.000 title claims abstract description 122
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 107
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 106
- 239000000463 material Substances 0.000 title claims abstract description 85
- 238000002360 preparation method Methods 0.000 title claims abstract description 19
- 238000006243 chemical reaction Methods 0.000 claims abstract description 17
- 150000003863 ammonium salts Chemical class 0.000 claims abstract description 14
- 238000004729 solvothermal method Methods 0.000 claims abstract description 11
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 7
- 239000011358 absorbing material Substances 0.000 claims description 28
- 238000000034 method Methods 0.000 claims description 22
- 238000010521 absorption reaction Methods 0.000 claims description 18
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical group [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims description 15
- 239000001099 ammonium carbonate Substances 0.000 claims description 15
- 235000012501 ammonium carbonate Nutrition 0.000 claims description 15
- 239000012188 paraffin wax Substances 0.000 claims description 12
- 239000011230 binding agent Substances 0.000 claims description 10
- 230000035484 reaction time Effects 0.000 claims description 7
- 239000011258 core-shell material Substances 0.000 claims description 6
- 230000001476 alcoholic effect Effects 0.000 claims description 2
- 150000003839 salts Chemical class 0.000 claims 2
- 230000000694 effects Effects 0.000 abstract description 24
- 150000002505 iron Chemical class 0.000 abstract description 7
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 14
- 239000002131 composite material Substances 0.000 description 12
- 230000008569 process Effects 0.000 description 12
- 239000000243 solution Substances 0.000 description 11
- 238000002474 experimental method Methods 0.000 description 8
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 7
- USFZMSVCRYTOJT-UHFFFAOYSA-N Ammonium acetate Chemical group N.CC(O)=O USFZMSVCRYTOJT-UHFFFAOYSA-N 0.000 description 7
- 239000005695 Ammonium acetate Substances 0.000 description 7
- 229940043376 ammonium acetate Drugs 0.000 description 7
- 235000019257 ammonium acetate Nutrition 0.000 description 7
- 239000011259 mixed solution Substances 0.000 description 7
- 230000015572 biosynthetic process Effects 0.000 description 6
- 238000003917 TEM image Methods 0.000 description 5
- -1 hydroxide ions Chemical class 0.000 description 5
- 230000010287 polarization Effects 0.000 description 5
- 238000001878 scanning electron micrograph Methods 0.000 description 5
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 229910052742 iron Inorganic materials 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- NQXWGWZJXJUMQB-UHFFFAOYSA-K iron trichloride hexahydrate Chemical compound O.O.O.O.O.O.[Cl-].Cl[Fe+]Cl NQXWGWZJXJUMQB-UHFFFAOYSA-K 0.000 description 4
- 229910000069 nitrogen hydride Inorganic materials 0.000 description 4
- 230000002195 synergetic effect Effects 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- KAESVJOAVNADME-UHFFFAOYSA-N 1H-pyrrole Natural products C=1C=CNC=1 KAESVJOAVNADME-UHFFFAOYSA-N 0.000 description 3
- QTBSBXVTEAMEQO-UHFFFAOYSA-N Acetic acid Chemical compound CC(O)=O QTBSBXVTEAMEQO-UHFFFAOYSA-N 0.000 description 3
- CWYNVVGOOAEACU-UHFFFAOYSA-N Fe2+ Chemical compound [Fe+2] CWYNVVGOOAEACU-UHFFFAOYSA-N 0.000 description 3
- 238000005411 Van der Waals force Methods 0.000 description 3
- 238000002441 X-ray diffraction Methods 0.000 description 3
- 230000009471 action Effects 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-N carbonic acid Chemical compound OC(O)=O BVKZGUZCCUSVTD-UHFFFAOYSA-N 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 229940044631 ferric chloride hexahydrate Drugs 0.000 description 3
- 229960004887 ferric hydroxide Drugs 0.000 description 3
- 229910001448 ferrous ion Inorganic materials 0.000 description 3
- IEECXTSVVFWGSE-UHFFFAOYSA-M iron(3+);oxygen(2-);hydroxide Chemical compound [OH-].[O-2].[Fe+3] IEECXTSVVFWGSE-UHFFFAOYSA-M 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 235000019270 ammonium chloride Nutrition 0.000 description 2
- BFNBIHQBYMNNAN-UHFFFAOYSA-N ammonium sulfate Chemical compound N.N.OS(O)(=O)=O BFNBIHQBYMNNAN-UHFFFAOYSA-N 0.000 description 2
- 229910052921 ammonium sulfate Inorganic materials 0.000 description 2
- 235000011130 ammonium sulphate Nutrition 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 238000005253 cladding Methods 0.000 description 2
- 229910021506 iron(II) hydroxide Inorganic materials 0.000 description 2
- NCNCGGDMXMBVIA-UHFFFAOYSA-L iron(ii) hydroxide Chemical compound [OH-].[OH-].[Fe+2] NCNCGGDMXMBVIA-UHFFFAOYSA-L 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 229910052760 oxygen Inorganic materials 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- VTLYFUHAOXGGBS-UHFFFAOYSA-N Fe3+ Chemical compound [Fe+3] VTLYFUHAOXGGBS-UHFFFAOYSA-N 0.000 description 1
- WQZGKKKJIJFFOK-GASJEMHNSA-N Glucose Natural products OC[C@H]1OC(O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-GASJEMHNSA-N 0.000 description 1
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- WQZGKKKJIJFFOK-VFUOTHLCSA-N beta-D-glucose Chemical compound OC[C@H]1O[C@@H](O)[C@H](O)[C@@H](O)[C@@H]1O WQZGKKKJIJFFOK-VFUOTHLCSA-N 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010668 complexation reaction Methods 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000005670 electromagnetic radiation Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229940032296 ferric chloride Drugs 0.000 description 1
- 229910001447 ferric ion Inorganic materials 0.000 description 1
- 229940032950 ferric sulfate Drugs 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000008103 glucose Substances 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical group Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- RUTXIHLAWFEWGM-UHFFFAOYSA-H iron(3+) sulfate Chemical compound [Fe+3].[Fe+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O RUTXIHLAWFEWGM-UHFFFAOYSA-H 0.000 description 1
- 229910000360 iron(III) sulfate Inorganic materials 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920001690 polydopamine Polymers 0.000 description 1
- 125000000168 pyrrolyl group Chemical group 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 239000012265 solid product Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 238000012795 verification Methods 0.000 description 1
Images
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G49/00—Compounds of iron
- C01G49/02—Oxides; Hydroxides
- C01G49/08—Ferroso-ferric oxide [Fe3O4]
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K3/00—Materials not provided for elsewhere
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
- C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
- C01P2004/04—Particle morphology depicted by an image obtained by TEM, STEM, STM or AFM
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/80—Particles consisting of a mixture of two or more inorganic phases
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
- Hard Magnetic Materials (AREA)
- Compounds Of Iron (AREA)
Abstract
The invention discloses a carbon-coated magnetic ferroferric oxide hollow sphere material, and a preparation method and application thereof. The preparation method comprises the following steps: carrying out solvothermal reaction on iron salt, ammonium salt and an alcohol solution to obtain a magnetic ferroferric oxide hollow sphere, mixing the magnetic ferroferric oxide hollow sphere with a carbon source, and carrying out closed heating reaction to obtain a carbon-coated magnetic ferroferric oxide hollow sphere material; wherein, the solvothermal reaction conditions are as follows: the temperature is 80-250 ℃, and the time is 10.5-17.5 h. The material provided by the invention not only has excellent wave-absorbing effect, but also has simple and easy preparation method, low cost and great industrial application prospect.
Description
Technical Field
The invention belongs to the technical field of electromagnetic wave absorbing materials, and relates to a carbon-coated magnetic ferroferric oxide hollow sphere material, and a preparation method and application thereof.
Background
The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.
With the appearance of a great number of various electrical and electronic devices in daily life of people, electromagnetic radiation pollution interferes with normal life of people while providing great convenience for life of people, even threatens normal functions of human bodies in serious cases, and becomes the fifth largest pollution seriously threatening human health. The electromagnetic waves can also interfere with the normal operation of other electronic equipment and damage the precise electronic equipment. The serious electromagnetic leakage may cause various kinds of information of people to be scattered in a space by the leaked electromagnetic waves. In the aspect of military weaponry, the electromagnetic wave absorbing material is an important component of radar stealth technology and plays an important role in military weaponry research. Therefore, electromagnetic wave absorbing materials are attracting more and more attention and attention. The inventor finds that the existing magnetic wave-absorbing material has the defects of complex preparation method, poor impedance matching, poor electromagnetic wave absorption performance and the like, and the existing material cannot have a strong absorption effect on the electromagnetic waves of 8-12 GHz.
Disclosure of Invention
In order to solve the defects of the prior art, the invention aims to provide the carbon-coated magnetic ferroferric oxide hollow sphere material, and the preparation method and the application thereof, which not only have excellent wave absorbing effect, but also have simple and easy preparation method, low cost and great industrial application prospect.
In order to achieve the purpose, the technical scheme of the invention is as follows:
on the one hand, the carbon-coated magnetic ferroferric oxide hollow sphere material is of a nano hollow core-shell structure, the nano hollow core-shell structure is composed of a shell and an inner core, and the inner core is a magnetic ferroferric oxide hollow sphere.
The carbon-coated magnetic ferroferric oxide hollow sphere material has the advantages that the carbon layer is coated on the surface of the magnetic ferroferric oxide hollow sphere through Van der Waals force, and good impedance matching is obtained through the synergistic effect of the dielectric loss of the carbon layer and the magnetic loss of the magnetic ferroferric oxide, so that the material has excellent wave-absorbing performance. Compare in carbon cladding magnetism ferroferric oxide solid sphere, when the incident electromagnetic wave got into the clean shot inside, can carry out more reflection scattering loss in the cavity inside, and reflection loss path is longer in the cavity, and the electromagnetic wave of dissipation is more, and it is better to inhale the wave property promptly.
The carbon-coated magnetic ferroferric oxide hollow sphere material has the advantages that due to the interface between the carbon layer and the magnetic ferroferric oxide hollow sphere and the large specific surface area of the inner cavity wall of the magnetic ferroferric oxide, when electromagnetic waves are incident into the material, more interface polarization can be generated, the dissipation of the electromagnetic waves is facilitated, and the wave absorbing performance of the material is improved.
On the other hand, the preparation method of the carbon-coated magnetic ferroferric oxide hollow ball material comprises the steps of carrying out solvothermal reaction on iron salt, ammonium salt and an alcohol solution to obtain a magnetic ferroferric oxide hollow ball, mixing the magnetic ferroferric oxide hollow ball with a carbon source, and carrying out closed heating reaction to obtain the carbon-coated magnetic ferroferric oxide hollow ball material; wherein, the solvothermal reaction conditions are as follows: the temperature is 80-250 ℃, and the time is 10.5-17.5 h.
In the solvent thermal reaction system of the iron salt, the ammonium salt and the alcoholic solution, the magnetic ferroferric oxide hollow spheres grow large in nucleation in the reaction process, and a hollow structure is formed under the action of the ammonium salt through the Cokendall effect. Experiments show that when the time is 10h, a solid structure is obtained, and when the time is too long (18h), the excessive Kenkard effect causes the wall thickness of part of the hollow sphere to be too thin, so that the spherical damage is caused.
The carbon-coated magnetic ferroferric oxide hollow sphere material prepared by the optimized parameters obtains better impedance matching through the reasonable regulation and control of the thickness of the carbon layer and the hollow size of the magnetic ferroferric oxide and the synergistic effect of the dielectric loss of the carbon layer and the magnetic loss of the magnetic ferroferric oxide, thereby having excellent wave-absorbing performance.
According to the invention, through a closed heating reaction, the carbon layer can generate more interface polarization in the formation process of the surface of the magnetic ferroferric oxide hollow sphere, so that the wave absorbing performance of the carbon layer is improved.
The ammonium salt is ammonium acetate, ammonium sulfate, ammonium chloride or ammonium carbonate, however, experiments show that the carbon-coated magnetic ferroferric oxide hollow sphere material prepared by the ammonium carbonate has better wave absorbing performance.
In a third aspect, the carbon-coated magnetic ferroferric oxide hollow sphere material is applied to the field of electromagnetic wave absorption materials.
In a fourth aspect, the electromagnetic wave absorbing material is a layered structure and is composed of the carbon-coated magnetic ferroferric oxide hollow sphere material and a binder.
The thickness of the layered structure influences the wave absorbing performance of the electromagnetic wave absorbing material, and experiments prove that when the thickness is 3.5-3.6 mm, the wave absorbing effect is better, the absorption of the electromagnetic wave of 8-12 GHz can reach-71 dB, and the effective absorption bandwidth can reach 4.3 GHz.
In a fifth aspect, a preparation method of the electromagnetic wave absorbing material is to mix the carbon-coated magnetic ferroferric oxide hollow sphere material and a binder.
In a sixth aspect, the electromagnetic wave absorbing material is applied to the field of electromagnetic wave interference resistance.
The invention has the beneficial effects that:
the carbon-coated magnetic ferroferric oxide hollow sphere material prepared by the method has the advantages of simple synthesis method, controllable appearance, short synthesis period and strong absorption. The final product can be obtained only by one-time hydrothermal and one-time roasting in the preparation process, and for the prepared carbon-coated magnetic ferroferric oxide hollow sphere material, on one hand, due to rich interfaces between the two materials, interface polarization can be provided, and the dielectric loss of the material to electromagnetic waves is increased, and on the other hand, due to proper impedance matching of the material, as much electromagnetic waves as possible can enter the material, so that the whole process is simple in process, low in cost and good in effect.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.
Fig. 1 is an XRD diffraction pattern of the carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 1 of the present invention.
FIG. 2 is an SEM image of a carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 1 of the invention; wherein a and b are SEM images of the magnetic ferroferric oxide hollow sphere material; and c is an SEM image and an EDS (electronic discharge system) surface scanning image of the carbon-coated magnetic ferroferric oxide hollow sphere material.
FIG. 3 is a TEM image of the carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 1 of the present invention.
FIG. 4 is a reflection loss diagram of the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material prepared in example 1 of the present invention.
FIG. 5 is a TEM image of the carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 4 of the present invention.
Fig. 6 is a reflection loss diagram of the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material prepared in embodiment 4 of the invention.
FIG. 7 is a TEM image of the carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 5 of the present invention.
Fig. 8 is a reflection loss diagram of the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material prepared in embodiment 5 of the invention.
Detailed Description
It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments according to the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.
The invention provides a carbon-coated magnetic ferroferric oxide hollow sphere material, and a preparation method and application thereof, in view of the defects of complex preparation method, poor impedance matching, poor electromagnetic wave absorption performance and the like of the existing magnetic wave absorbing material, and the existing material cannot have a strong absorption effect on 8-12 GHz electromagnetic waves.
The invention provides a typical embodiment of a carbon-coated magnetic ferroferric oxide hollow sphere material, which is a nano hollow core-shell structure, wherein the nano hollow core-shell structure is composed of a shell and an inner core, and the inner core is a magnetic ferroferric oxide hollow sphere.
The carbon layer is coated on the surface of the magnetic ferroferric oxide hollow sphere through Van der Waals force, and good impedance matching is obtained through the synergistic effect of the dielectric loss of the carbon layer and the magnetic loss of the magnetic ferroferric oxide, so that the magnetic hollow sphere has excellent wave-absorbing performance. The interface between the carbon layer and the magnetic ferroferric oxide hollow sphere and the large specific surface area of the internal cavity wall of the magnetic ferroferric oxide enable electromagnetic waves to be incident into the material, so that more interface polarization can be generated, dissipation of the electromagnetic waves is facilitated, and the wave absorbing performance of the material is improved.
In some examples of this embodiment, the shell is a carbon layer, the wall thickness of the hollow sphere, and the diameter ratio of the hollow sphere are 5-15: 40-60: 650-700.
When the shape and size are fixed, the wall thickness is thinner, namely, the cavity space in the hollow ball is larger, when incident electromagnetic waves enter the hollow ball, more reflection scattering loss can be carried out, the reflection loss path in the cavity is longer, the dissipated electromagnetic waves are more, and the wave absorbing performance is better.
The carbon layer with increased thickness has impedance mismatching with the magnetic ferroferric oxide hollow sphere material, so that the wave absorbing performance of the carbon layer is poor.
Experiments show that the material with the size proportion has better wave-absorbing performance.
The invention also provides a preparation method of the carbon-coated magnetic ferroferric oxide hollow sphere material, which comprises the steps of carrying out solvothermal reaction on iron salt, ammonium salt and an alcohol solution to obtain a magnetic ferroferric oxide hollow sphere, mixing the magnetic ferroferric oxide hollow sphere with a carbon source, and carrying out closed heating reaction to obtain the carbon-coated magnetic ferroferric oxide hollow sphere material; wherein, the solvothermal reaction conditions are as follows: the temperature is 80-250 ℃, and the time is 10.5-17.5 h.
The carbon-coated magnetic ferroferric oxide hollow sphere material prepared by the optimized parameters obtains better impedance matching through the reasonable regulation and control of the thickness of the carbon layer and the hollow size of the magnetic ferroferric oxide and the synergistic effect of the dielectric loss of the carbon layer and the magnetic loss of the magnetic ferroferric oxide, thereby having excellent wave-absorbing performance. Meanwhile, the carbon layer can generate more interface polarization in the formation process of the surface of the magnetic ferroferric oxide hollow sphere through closed heating reaction, so that the wave absorbing performance of the magnetic ferroferric oxide hollow sphere is improved.
The ammonium salt is ammonium acetate, ammonium sulfate, ammonium chloride or ammonium carbonate, however, experiments show that the carbon-coated magnetic ferroferric oxide hollow sphere material prepared by the ammonium carbonate has better wave absorbing performance. This is because the process of preparing ferroferric oxide with ammonium carbonate is different from the process of preparing ferroferric oxide with ammonium salts such as ammonium acetate. When ammonium salts such as ammonium acetate are adopted, the process is as follows: hydrolysis of ammonium acetate to acetic acid and NH3·H2O,NH3·H2And (2) ionizing hydroxide ions by using O, combining the hydroxide ions with ferric ions and ferrous ions to generate ferric hydroxide and ferrous hydroxide, combining the ferric hydroxide and the ferrous hydroxide to generate ferroferric oxide, and in the process of forming the ferroferric oxide, discharging ammonia gas from the interior of the ferroferric oxide to form a hollow structure. However, when ammonium carbonate is used, the process is: along with the rise of temperature and pressure, ammonium carbonate is firstly decomposed, and under the action of a closed system, ammonium carbonate is decomposed to generate NH3·H2O and carbonic acid, NH3·H2O ionizes to generate hydroxide radical, and the hydroxide radical combines with iron ion and ferrous ion to generate ferric hydroxideFerrous hydroxide, iron ion, ferrous ion and carbonic acid carry out temporary complexation simultaneously, form the microballon jointly, and along with the reaction goes on, the ammonia of cladding in the microballon is constantly discharged, and the carbon dioxide that carbonic acid resoluble is discharged simultaneously to make and form hollow structure. Compared with the formation of a hollow structure of the carbon-coated magnetic ferroferric oxide hollow sphere material, the hollow structure is formed by the ammonium carbonate under the action of ammonium ions through the Cokendall effect, carbon dioxide can be formed at carbonate, the micro appearance of the hollow structure can be adjusted through the Cokendall effect, meanwhile, the formation process of the ferroferric oxide can be adjusted by the carbonate in the formation process of the ferroferric oxide, the micro appearance of the wall of the hollow structure is adjusted, the micro appearance of the hollow structure is further adjusted by the ammonium carbonate, and the wave absorbing performance of the carbon-coated magnetic ferroferric oxide hollow sphere material is greatly improved.
In some embodiments of this embodiment, the iron salt is ferric chloride, ferric sulfate, or ferric hydroxide.
In some embodiments of this embodiment, the alcohol solution is ethanol or ethylene glycol.
In some examples of this embodiment, the iron salt, the ammonium salt, and the alcohol solution are added in a ratio of 0.5-3.0 g to 2.0-12.0 g to 10-1000 mL. The effect is better when the ratio is 0.5-2.0 g: 2.0-6.0 g: 50-1000 mL.
In some embodiments of this embodiment, the solvothermal reaction conditions are: the temperature is 150-230 ℃, and the time is 15.5-16.5 h. Under the condition, the wall thickness of the prepared hollow sphere is thin, and the wave-absorbing performance is better.
In some embodiments of this embodiment, the carbon source is pyrrole, glucose, or polydopamine.
In some embodiments of the embodiment, the adding ratio of the magnetic ferroferric oxide hollow sphere material to the carbon source is 0.1-2.0 g: 2-8 g. When the ratio is 0.1-1.0g to 2-5g, the effect is better.
In some examples of this embodiment, the conditions for the closed heating reaction are: the temperature is 300-900 ℃, and the reaction time is 2-18 h. When the reaction temperature is 300-600 ℃ and the reaction time is 2-10 h, the effect is better. When the reaction temperature is 550 ℃ and the reaction time is 5.5 hours, the effect is more excellent.
The invention provides an application of the carbon-coated magnetic ferroferric oxide hollow sphere material in the field of electromagnetic wave absorbing materials.
In a fourth embodiment of the present invention, an electromagnetic wave absorbing material having a layered structure is provided, which is composed of the carbon-coated magnetic ferroferric oxide hollow sphere material and a binder.
The thickness of the layered structure influences the wave absorbing performance of the electromagnetic wave absorbing material, and experiments prove that when the thickness is 3.5-3.6 mm, the wave absorbing effect is better, the absorption of low-frequency electromagnetic waves can reach-71 dB, and the effective absorption bandwidth can reach 4.3 GHz.
In some embodiments of this embodiment, the binder is paraffin wax. The paraffin has a good wave-transmitting effect, the wave-absorbing effect is improved by matching the paraffin with the carbon-coated magnetic ferroferric oxide hollow ball material, and the wave-absorbing effect can be further improved by compounding the paraffin and the carbon-coated magnetic ferroferric oxide hollow ball material.
In one or more embodiments, the mass ratio of the carbon-coated magnetic ferroferric oxide hollow sphere material to the paraffin is 2: 3-5.
In a fifth embodiment of the present invention, a method for preparing the electromagnetic wave absorbing material is provided, wherein the carbon-coated magnetic ferroferric oxide hollow sphere material and a binder are mixed.
In some examples of this embodiment, the binder is paraffin wax and the mixing temperature is 45-55 ℃. The fluidity of the paraffin can be increased at the temperature, and the paraffin is favorably and fully mixed with the carbon-coated magnetic ferroferric oxide hollow sphere material.
In a sixth embodiment of the present invention, an application of the electromagnetic wave absorbing material in the field of electromagnetic wave interference resistance is provided.
In order to make the technical solution of the present invention more clearly understood by those skilled in the art, the technical solution of the present invention will be described in detail below with reference to specific examples and comparative examples.
Example 1
A preparation method of a carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material comprises the following steps:
(1) adding 1.0g of ferric trichloride hexahydrate and 3.0g of ammonium carbonate into 80mL of glycol solution, and uniformly dispersing to obtain a mixed solution A;
(2) transferring the mixed solution A in the step (1) into a polytetrafluoroethylene-lined steel reaction kettle, and heating to 200 ℃ for 16 h. After the reactant is naturally cooled to room temperature, the obtained solid product is centrifugally separated, washed by ethanol/water mixed solution for many times, and dried for 12 hours under the vacuum condition of 60 ℃. Obtaining the magnetic ferroferric oxide hollow sphere material.
(3) And (3) uniformly mixing 0.4g of magnetic ferroferric oxide hollow sphere material and 3g of pyrrole to obtain a mixture B, transferring the mixture B into a stainless steel reaction kettle, heating the mixture B to 550 ℃ at a high temperature in a tubular furnace, and preserving the heat for 5.5 hours to obtain the carbon-coated magnetic ferroferric oxide hollow sphere material.
FIG. 1 is an XRD (X-ray diffraction) pattern of the carbon-coated magnetic ferroferric oxide hollow sphere material prepared in example 1, and shows that the synthesized composite material contains Fe and O and has a standard diffraction pattern of Fe3O4(JCPDS No.89-0688) has better goodness of fit. Under hydrothermal condition, iron salt and ammonium salt produce ferroferric oxide.
Fig. 2 a is an SEM image of the magnetic ferroferric oxide hollow sphere prepared in example 1, and fig. 2 b is an SEM image of the carbon-coated magnetic ferroferric oxide hollow sphere material, and it can be seen from the images that the diameter of the magnetic ferroferric oxide hollow sphere is about 680nm, the particle size distribution is relatively uniform, and the surface is relatively smooth. The diameter of the carbon-coated magnetic ferroferric oxide hollow sphere material is about 700nm, which shows that the surface becomes rough due to the increase of the size of the coated carbon layer. The carbon layer is coated on the surface of the magnetic ferroferric oxide hollow sphere through Van der Waals force. Fig. 2C is a partial EDS surface scan of the carbon-coated magnetic ferriferrous oxide hollow sphere, and the result shows that the carbon-coated magnetic ferriferrous oxide hollow sphere is composed of three elements, that is, Fe, O, and C, which also indicates the existence of a carbon layer on the surface of the magnetic ferriferrous oxide hollow sphere.
Fig. 3 is a TEM image of the carbon-coated magnetic ferroferric oxide hollow sphere, and it can be seen from the TEM image that the diameter size of the carbon-coated magnetic ferroferric oxide hollow sphere is about 700nm and the color in the middle is lighter, which indicates that the carbon-coated magnetic ferroferric oxide hollow sphere has a hollow structure and the wall thickness is about 50 nm.
Example 2
In step (1), 1.0g of ferric chloride hexahydrate and 3.5g of ammonium carbonate were added to 120mL of an ethylene glycol solution and uniformly dispersed to obtain a mixed solution A, as compared with example 1, and other conditions were not changed. And then preparing the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material according to the method of the embodiment 2.
Example 3
In step (1), 1.5g of ferric chloride hexahydrate and 3.0g of ammonium carbonate were added to 120mL of an ethylene glycol solution and uniformly dispersed to obtain a mixed solution A, as compared with example 1, and other conditions were not changed. And then preparing the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material according to the method of the embodiment 2.
Experimental example 1
The carbon-coated magnetic ferroferric oxide hollow sphere material prepared in the example 1 is mixed with paraffin according to the mass ratio of 2:3, and the temperature in the mixing process is 50 ℃. And stirring uniformly to obtain the carbon-coated magnetic ferroferric oxide hollow sphere material composite wave-absorbing material. The carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material is respectively made into materials with the thicknesses of 2.0mm, 3.0mm, 3.5mm and 4.0mm, electromagnetic waves are generated on one side of the material, and the loss of the electromagnetic waves is detected on the other side of the material, so that the result shown in figure 4 is obtained.
As can be seen from fig. 4, when the thickness is 3.54mm, the absorption effect on the electromagnetic wave is the best, and an effect of approximately-71 dB is obtained. When the frequency is 6.00-10.32 GHz, the reflection loss is less than-10 dB, namely the effective absorption bandwidth reaches 4.30 GHz.
The carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material is prepared into a thickness of 3.54mm for experimental verification, and the result is consistent with the conclusion.
Example 4
In comparison with example 1, 1.0g of ferric chloride hexahydrate and 5.0g of ammonium acetate were added to 80mL of an ethylene glycol solution and uniformly dispersed to obtain a mixed solution A. Other conditions were unchanged. The carbon-coated magnetic ferroferric oxide hollow sphere material is obtained, and as shown in figure 5, the diameter of the hollow sphere is about 700nm, and the wall thickness is about 50 nm. Then, the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material is prepared according to the method of the experimental example 1, and an electromagnetic wave loss experiment is carried out according to the experimental example 1, and as shown in fig. 6, when the thickness is 2.41mm, the absorption effect on the electromagnetic wave is the best, and the effect close to-54.66 dB is obtained. When the frequency is 8.76-12.50 GHz, the reflection loss is less than-10 dB, namely the effective absorption bandwidth reaches 3.74 GHz. The carbon-coated magnetic ferroferric oxide hollow sphere material prepared by ammonium acetate has better performance no matter the effective absorption bandwidth or the maximum reflection loss value is not the same as the carbon-coated magnetic ferroferric oxide hollow sphere prepared by ammonium carbonate.
Example 5
Compared with example 1, the solvothermal reaction temperature of the mixed solution A is 200 ℃, and the reaction time is 12 h. Other conditions were unchanged. The carbon-coated magnetic ferroferric oxide hollow sphere material is obtained, and as shown in figure 7, the diameter of the hollow sphere is about 700nm, and the wall thickness is about 250 nm. Then, the carbon-coated magnetic ferroferric oxide hollow sphere composite wave-absorbing material is prepared according to the method of the experimental example 1, and an electromagnetic wave loss experiment is carried out according to the experimental example 1, and as shown in fig. 8, when the thickness is 5.17mm, the absorption effect on the electromagnetic wave is the best, and the effect close to-27.25 dB is obtained. When the frequency is 8.80-12.80 GHz, the reflection loss is less than-10 dB, namely the effective absorption bandwidth reaches 4.00 GHz.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (10)
1. A carbon-coated magnetic ferroferric oxide hollow sphere material is characterized by being of a nano hollow core-shell structure, wherein the nano hollow core-shell structure is composed of a shell and an inner core, and the inner core is a magnetic ferroferric oxide hollow sphere.
2. The carbon-coated magnetic ferroferric oxide hollow sphere material as claimed in claim 1, wherein the shell is a carbon layer, the wall thickness of the carbon layer and the hollow sphere and the diameter ratio of the hollow sphere are 5-15: 40-60: 650-700.
3. A preparation method of a carbon-coated magnetic ferroferric oxide hollow ball material is characterized in that ferric salt, ammonium salt and an alcohol solution are subjected to solvothermal reaction to obtain a magnetic ferroferric oxide hollow ball, and the magnetic ferroferric oxide hollow ball is mixed with a carbon source and then subjected to closed heating reaction to obtain the carbon-coated magnetic ferroferric oxide hollow ball material; wherein, the solvothermal reaction conditions are as follows: the temperature is 80-250 ℃, and the time is 10.5-17.5 h;
preferably, the ammonium salt is ammonium carbonate.
4. The method for preparing the carbon-coated magnetic ferroferric oxide hollow sphere material according to claim 3, wherein the adding ratio of the ferric salt, the ammonium salt and the alcoholic solution is 0.5-3.0 g, 2.0-12.0 g and 10-1000 mL; preferably, the ratio is 0.5-2.0 g: 2.0-6.0 g: 50-1000 mL;
or, the solvothermal reaction conditions are as follows: the temperature is 150-230 ℃, and the time is 15.5-16.5 h.
5. The method for preparing the carbon-coated magnetic ferroferric oxide hollow sphere material according to claim 3, wherein the adding ratio of the magnetic ferroferric oxide hollow sphere material to the carbon source is 0.1-2.0 g: 2-8 g; preferably, the ratio is 0.1-1.0g to 2-5 g.
6. The method for preparing the carbon-coated magnetic ferroferric oxide hollow sphere material according to claim 3, wherein the conditions of the closed heating reaction are as follows: the temperature is 300-900 ℃, and the reaction time is 2-18 h; preferably, the reaction temperature is 300-600 ℃, and the reaction time is 2-10 h; further preferably, the reaction temperature is 550 ℃ and the reaction time is 5.5 h.
7. An application of the carbon-coated magnetic ferroferric oxide hollow sphere material according to claim 1 or 2 or the carbon-coated magnetic ferroferric oxide hollow sphere material obtained by the preparation method according to any one of claims 3 to 6 in the field of electromagnetic wave absorption materials.
8. An electromagnetic wave absorbing material, which is characterized by having a layered structure and comprising the carbon-coated magnetic ferroferric oxide hollow sphere material according to claim 1 or 2 or the carbon-coated magnetic ferroferric oxide hollow sphere material obtained by the preparation method according to any one of claims 3 to 6 and a binder;
preferably, the thickness of the laminated structure is 3.5-3.6 mm;
preferably, the binder is paraffin wax; further preferably, the mass ratio of the carbon-coated magnetic ferroferric oxide hollow sphere material to the paraffin is 2: 3-5.
9. A method for preparing an electromagnetic wave absorbing material as claimed in claim 8, wherein the carbon-coated magnetic ferroferric oxide hollow sphere material is mixed with a binder;
preferably, the binder is paraffin wax, and the mixing temperature is 45-55 ℃.
10. An electromagnetic wave absorbing material as claimed in claim 8, for use in the field of interference rejection of electromagnetic waves.
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| CN113382623A (en) * | 2021-06-18 | 2021-09-10 | 西安交通大学 | Thermal and electromagnetic multifunctional protector and preparation method thereof |
| CN113462357A (en) * | 2021-07-02 | 2021-10-01 | 合肥工业大学 | Wave-absorbing particles and preparation method and application of composite material thereof |
| CN114540985A (en) * | 2022-01-17 | 2022-05-27 | 山东大学 | Preparation method and application of hollow core-shell fiber material |
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