CN115449343B - Silicon nitride wave-absorbing material and preparation method thereof - Google Patents
Silicon nitride wave-absorbing material and preparation method thereof Download PDFInfo
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- CN115449343B CN115449343B CN202211284570.9A CN202211284570A CN115449343B CN 115449343 B CN115449343 B CN 115449343B CN 202211284570 A CN202211284570 A CN 202211284570A CN 115449343 B CN115449343 B CN 115449343B
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- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 title claims abstract description 45
- 229910052581 Si3N4 Inorganic materials 0.000 title claims abstract description 44
- 239000011358 absorbing material Substances 0.000 title claims abstract description 24
- 238000002360 preparation method Methods 0.000 title claims abstract description 17
- 239000000463 material Substances 0.000 claims abstract description 42
- 239000011258 core-shell material Substances 0.000 claims abstract description 30
- 239000011521 glass Substances 0.000 claims abstract description 27
- 229910015136 FeMn Inorganic materials 0.000 claims abstract description 25
- 229910044991 metal oxide Inorganic materials 0.000 claims abstract description 19
- 150000004706 metal oxides Chemical class 0.000 claims abstract description 19
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000007599 discharging Methods 0.000 claims abstract description 7
- 238000001035 drying Methods 0.000 claims abstract description 7
- 238000011049 filling Methods 0.000 claims abstract description 7
- 238000001914 filtration Methods 0.000 claims abstract description 7
- 238000010438 heat treatment Methods 0.000 claims abstract description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 7
- 150000007524 organic acids Chemical class 0.000 claims abstract description 7
- 239000012047 saturated solution Substances 0.000 claims abstract description 7
- 238000007789 sealing Methods 0.000 claims abstract description 7
- 239000012265 solid product Substances 0.000 claims abstract description 7
- 238000005406 washing Methods 0.000 claims abstract description 7
- 238000001816 cooling Methods 0.000 claims description 12
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims description 9
- JTPNRXUCIXHOKM-UHFFFAOYSA-N 1-chloronaphthalene Chemical compound C1=CC=C2C(Cl)=CC=CC2=C1 JTPNRXUCIXHOKM-UHFFFAOYSA-N 0.000 claims description 6
- RTBFRGCFXZNCOE-UHFFFAOYSA-N 1-methylsulfonylpiperidin-4-one Chemical compound CS(=O)(=O)N1CCC(=O)CC1 RTBFRGCFXZNCOE-UHFFFAOYSA-N 0.000 claims description 6
- JFCQEDHGNNZCLN-UHFFFAOYSA-N anhydrous glutaric acid Natural products OC(=O)CCCC(O)=O JFCQEDHGNNZCLN-UHFFFAOYSA-N 0.000 claims description 6
- 150000001732 carboxylic acid derivatives Chemical group 0.000 claims description 6
- MVPPADPHJFYWMZ-UHFFFAOYSA-N chlorobenzene Chemical compound ClC1=CC=CC=C1 MVPPADPHJFYWMZ-UHFFFAOYSA-N 0.000 claims description 6
- CCUWGJDGLACFQT-UHFFFAOYSA-N 2,2,3,3,4,4-hexafluoropentanedioic acid Chemical compound OC(=O)C(F)(F)C(F)(F)C(F)(F)C(O)=O CCUWGJDGLACFQT-UHFFFAOYSA-N 0.000 claims description 4
- 239000003960 organic solvent Substances 0.000 claims description 4
- YPJUNDFVDDCYIH-UHFFFAOYSA-N perfluorobutyric acid Chemical compound OC(=O)C(F)(F)C(F)(F)C(F)(F)F YPJUNDFVDDCYIH-UHFFFAOYSA-N 0.000 claims description 4
- 238000000034 method Methods 0.000 claims 1
- 230000000694 effects Effects 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 230000010287 polarization Effects 0.000 abstract description 2
- 239000002131 composite material Substances 0.000 description 5
- 239000002070 nanowire Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 239000003575 carbonaceous material Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 150000008422 chlorobenzenes Chemical class 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000003989 dielectric material Substances 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000012188 paraffin wax Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 229910021426 porous silicon Inorganic materials 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 150000003613 toluenes Chemical class 0.000 description 1
- 230000035899 viability Effects 0.000 description 1
- 239000011800 void material Substances 0.000 description 1
Classifications
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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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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
Abstract
The invention belongs to the technical field of functional material manufacturing, and particularly relates to a silicon nitride wave-absorbing material and a preparation method thereof. A silicon nitride wave-absorbing material is prepared from FeMn@C 60 The core-shell structure material is compounded with silicon nitride; the FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps: step 1: metal oxide, organic acid, C 60 Filling the saturated solution into a glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube; step 2: placing the glass tube into an oven and heating; step 3: filtering the solid product, washing for 3 times, and drying to obtain FeMn@C 60 A core-shell structural material. FeMn@C 60 The heterogeneous interface between the core and the shell in the core-shell structure material can also generate an interface polarization effect, so that the dielectric loss of the material is increased, the wave absorbing performance of the material is improved, the density of the material is reduced, and the dielectric loss capacity of the material is improved by repeated reflection between the core and the shell.
Description
Technical Field
The invention belongs to the technical field of functional material manufacturing, and particularly relates to a silicon nitride wave-absorbing material and a preparation method thereof.
Background
In recent years, electromagnetic pollution has become an increasingly serious problem with the widespread use of electromagnetic waves in people's lives. For example, electromagnetic waves radiated by a mobile phone can affect the normal operation of precision electronic medical instruments; electromagnetic waves can also severely interfere with communications facilities onboard an aircraft; electromagnetic leakage of electronic devices such as computers may cause leakage of important information; in military aspect, development of radar detection technology based on electromagnetic waves will seriously threaten the viability of aircraft, tanks and vessels; moreover, electromagnetic waves are also a long-term hazard to the human body. Therefore, the development of the wave-absorbing material with excellent performance has important significance in both military and civil aspects.
The carbon material belongs to one of dielectric materials, has the advantages of ultralow density, high conductivity, excellent microwave absorption performance, environmental stability and the like, and the single carbon material cannot meet the requirements in the aspects of mechanical property, strength and the like. Silicon nitride not only has high strength, abrasion resistance, corrosion resistance, oxidation resistance and good thermal shock resistance and mechanical impact resistance at room temperature and high temperature, but also has low dielectric constant and electromagnetic loss, and the composite use of carbon materials can mutually make up the defects of each other.
Disclosure of Invention
The invention provides a silicon nitride wave-absorbing material and a preparation method thereof in order to overcome the problems in the prior art.
The technical scheme provided by the invention is as follows:
a silicon nitride wave-absorbing material is prepared from FeMn@C 60 The core-shell structure material is compounded with silicon nitride;
the FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, organic acid, 1L of C 60 Filling the saturated solution into a glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: putting the glass tube in the step 1 into an oven, heating to 160-200 ℃, keeping for 48-96h, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube and preparing C again 60 Washing the saturated solution with organic solvent for 3 times, and drying to obtain FeMn@C 60 A core-shell structural material.
Specifically, the molar ratio of FeO to MnO is 0.8-1.2:1.
specifically, the organic acid adopts any one of heptafluorobutyric acid, hexafluoroglutaric acid and glutaric acid, and the molar ratio of carboxylic acid functional groups to metal oxides in the organic acid is 0.5-3:1.
Specifically, in the step 1C 60 The organic solvent of the saturated solution is any one of chlorobenzene, toluene and 1-chloronaphthalene.
The invention also provides a preparation method of the silicon nitride wave-absorbing material, which comprises the steps of mixing FeMn@C 60 Core-shell structural material and nitrogenSilicon carbide is ground for 2-3h in a ball mill.
The invention provides a silicon nitride wave-absorbing material, wherein FeMn@C 60 The heterogeneous interface between the core and the shell in the core-shell structure material can generate an interface polarization effect, so that the dielectric loss of the material is increased, the wave absorbing performance of the material is improved, and the density of the material is reduced. Multiple reflections between the core and the shell increase the dielectric loss capability of the material. In addition, feMn@C 60 The core-shell structure material is compounded with the porous silicon nitride to form a more complex porous material, so that the void ratio is further improved, the number of interfaces is increased, and the wave absorbing performance of the material is improved. The complex formed by the iron and manganese metal elements has a certain magnetic consumption effect, and can further improve the wave absorbing performance of the material.
Drawings
FIG. 1 is a graph showing the real part of complex permittivity of example 4 of a silicon nitride wave-absorbing material as a function of frequency.
Fig. 2 is a graph of the imaginary part of the complex dielectric constant versus frequency for example 4 of a silicon nitride wave-absorbing material.
Fig. 3 is a graph showing the real part of the complex permeability constant of example 4 of a silicon nitride wave-absorbing material as a function of frequency.
Fig. 4 is a graph of the imaginary part of the complex permeability constant of example 4 of a silicon nitride wave-absorbing material as a function of frequency.
FIG. 5 is a graph showing the wave absorbing performance of example 4 of a silicon nitride wave absorbing material at different thicknesses of paraffin.
Detailed Description
For a further understanding of the present invention, preferred embodiments of the invention are described below in conjunction with the examples, but it should be understood that these descriptions are merely intended to illustrate further features and advantages of the invention, and are not limiting of the claims of the invention.
Example 1
A silicon nitride wave-absorbing material is prepared from FeMn@C 60 A composite material formed by a core-shell structure material and silicon nitride; the preparation method comprises the following steps: feMn@C 60 The core-shell structure material and silicon nitride are ground for 2 hours in a ball mill.
The silicon nitride is a silicon nitride nanowire.
The FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, heptafluorobutyric acid and 1L of C 60 Filling saturated chlorobenzene solution into a high-temperature-resistant glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: putting the glass tube in the step 1 into a baking oven capable of being heated and cooled by a program, heating to 160 ℃, keeping for 96 hours, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube, washing 3 times with chlorobenzene, and drying to obtain FeMn@C 60 A core-shell structural material.
The molar ratio of FeO to MnO in step 1 is 0.8:1.
the molar ratio of carboxylic acid functional groups to metal oxide in the heptafluorobutyric acid in step 1 was 0.5:1.
Example 2
A silicon nitride wave-absorbing material is prepared from FeMn@C 60 A composite material formed by a core-shell structure material and silicon nitride; the preparation method comprises the following steps: feMn@C 60 The core-shell structure material and silicon nitride are ground for 2.5 hours in a ball mill.
The silicon nitride is a silicon nitride nanowire.
The FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, hexafluoroglutaric acid, 1L of C 60 Filling saturated toluene solution into a high-temperature-resistant glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: placing the glass tube in the step 1 into a baking oven capable of being heated and cooled by a program, heating to 180 ℃, keeping for 80 hours, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube, washing 3 times with toluene, and drying to obtain FeMn@C 60 A core-shell structural material.
The molar ratio of FeO to MnO in the step 1 is 1:1.
the molar ratio of carboxylic acid functional groups to metal oxide in hexafluoroglutaric acid in step 1 is 1:1.
Example 3
A silicon nitride wave-absorbing material is prepared from FeMn@C 60 A composite material formed by a core-shell structure material and silicon nitride; the preparation method comprises the following steps: feMn@C 60 The core-shell structure material and silicon nitride are ground for 2.5 hours in a ball mill.
The silicon nitride is a silicon nitride nanowire.
The FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, glutaric acid, 1L of C 60 Filling a saturated 1-chloronaphthalene solution into a high-temperature-resistant glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: placing the glass tube in the step 1 into a baking oven capable of being heated and cooled by a program, heating to 200 ℃, keeping for 72 hours, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube, washing 3 times with 1-chloronaphthalene, and drying to obtain FeMn@C 60 A core-shell structural material.
The molar ratio of FeO to MnO in step 1 is 1.1:1.
the molar ratio of carboxylic acid functional groups to metal oxide in glutaric acid in step 1 was 2:1.
Example 4
A silicon nitride wave-absorbing material is prepared from FeMn@C 60 A composite material formed by a core-shell structure material and silicon nitride; the preparation method comprises the following steps: feMn@C 60 The core-shell structure material and silicon nitride are ground for 3 hours in a ball mill.
The silicon nitride is a silicon nitride nanowire.
The FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, glutaric acid,C of 1L 60 Filling a saturated 1-chloronaphthalene solution into a high-temperature-resistant glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: placing the glass tube in the step 1 into a baking oven capable of being heated and cooled by a program, heating to 200 ℃, keeping for 48 hours, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube, washing 3 times with 1-chloronaphthalene, and drying to obtain FeMn@C 60 A core-shell structural material.
The molar ratio of FeO to MnO in step 1 is 1.2:1.
the molar ratio of carboxylic acid functional groups to metal oxide in glutaric acid in step 1 was 3:1.
Claims (4)
1. A silicon nitride wave-absorbing material is characterized by comprising FeMn@C 60 The core-shell structure material is compounded with silicon nitride;
the FeMn@C 60 The preparation method of the core-shell structure material comprises the following steps:
step 1: 0.07mol of metal oxide, organic acid, 1L of C 60 Filling the saturated solution into a glass tube, discharging air in the glass tube by using nitrogen, and sealing the tube, wherein the metal oxide consists of FeO and MnO;
step 2: putting the glass tube in the step 1 into an oven, heating to 160-200 ℃, keeping for 48-96h, and then cooling to room temperature at a cooling rate of 5 ℃/h;
step 3: filtering the solid product in the glass tube and preparing C again 60 Washing the saturated solution with organic solvent for 3 times, and drying to obtain FeMn@C 60 A core-shell structural material;
the organic acid adopts any one of heptafluorobutyric acid, hexafluoroglutaric acid and glutaric acid, and the molar ratio of carboxylic acid functional groups to metal oxides in the organic acid is 0.5-3:1.
2. The silicon nitride wave absorbing material according to claim 1, wherein the molar ratio of FeO to MnO is 0.8-1.2:1.
3. the silicon nitride wave absorbing material according to claim 1, wherein C in step 1 60 The organic solvent of the saturated solution is any one of chlorobenzene, toluene and 1-chloronaphthalene.
4. A method for preparing a silicon nitride wave-absorbing material, which is characterized in that the silicon nitride wave-absorbing material according to any one of claims 1-3 is adopted, and FeMn@C60 core-shell structure material and silicon nitride are ground for 2-3 hours in a ball mill.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105032355A (en) * | 2015-08-24 | 2015-11-11 | 东华大学 | Preparation method for core-shell structure type carbon-coated magnetic nano particles |
| CN111320165A (en) * | 2018-12-13 | 2020-06-23 | 山东欧铂新材料有限公司 | Graphene oxide/carbonyl iron composite material, preparation method thereof and graphene-based wave-absorbing material |
| CN111517372A (en) * | 2020-05-11 | 2020-08-11 | 山西医科大学 | Fullerene coated Fe3O4Composite nano material and preparation method thereof |
| CN111970778A (en) * | 2020-08-25 | 2020-11-20 | 昆明理工大学 | Method and device for microwave high-flux sintering of powder block |
| CN115003142A (en) * | 2022-04-13 | 2022-09-02 | 哈尔滨工业大学（威海） | Preparation method of carbon-based/metal simple substance/boron nitride core-shell structure microwave absorbing material |
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- 2022-10-17 CN CN202211284570.9A patent/CN115449343B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105032355A (en) * | 2015-08-24 | 2015-11-11 | 东华大学 | Preparation method for core-shell structure type carbon-coated magnetic nano particles |
| CN111320165A (en) * | 2018-12-13 | 2020-06-23 | 山东欧铂新材料有限公司 | Graphene oxide/carbonyl iron composite material, preparation method thereof and graphene-based wave-absorbing material |
| CN111517372A (en) * | 2020-05-11 | 2020-08-11 | 山西医科大学 | Fullerene coated Fe3O4Composite nano material and preparation method thereof |
| CN111970778A (en) * | 2020-08-25 | 2020-11-20 | 昆明理工大学 | Method and device for microwave high-flux sintering of powder block |
| CN115003142A (en) * | 2022-04-13 | 2022-09-02 | 哈尔滨工业大学（威海） | Preparation method of carbon-based/metal simple substance/boron nitride core-shell structure microwave absorbing material |
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