CN112499685A - Preparation of MnO2Method for preparing @ porous carbon composite wave-absorbing material - Google Patents
Preparation of MnO2Method for preparing @ porous carbon composite wave-absorbing material Download PDFInfo
- Publication number
- CN112499685A CN112499685A CN202011353123.5A CN202011353123A CN112499685A CN 112499685 A CN112499685 A CN 112499685A CN 202011353123 A CN202011353123 A CN 202011353123A CN 112499685 A CN112499685 A CN 112499685A
- Authority
- CN
- China
- Prior art keywords
- mno
- preparing
- absorbing material
- composite wave
- prepared
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G45/00—Compounds of manganese
- C01G45/02—Oxides; Hydroxides
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
-
- 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
-
- 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
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
Abstract
The invention discloses a method for preparing MnO2A method for preparing a @ porous carbon (NPC) composite wave-absorbing material, relating to a method for preparing a composite wave-absorbing material. The invention aims to solve the technical problems of complex preparation method, high equipment requirement, high cost and single strongest absorption peak of the existing carbon-based microwave absorption material, and provides a method for preparing MnO by using Mn-MOF-74 as a template2A method for preparing a @ NPC composite wave-absorbing material. The invention comprises the following steps: firstly, preparing a Mn-MOF-74 template; secondly, pyrolysis; and thirdly, in-situ oxidation reduction. Compared with the existing carbon-based microwave absorbing material, the invention has the problems of complex preparation method, high equipment requirement, high cost and single microwave absorbing response frequency bandThe preparation method has the advantages of simple process, low production cost, simple and convenient subsequent treatment, no need of complex synthesis equipment and full-band microwave absorption response, and is suitable for industrial large-scale production and popularization and application.
Description
Technical Field
The invention relates to the technical field of composite wave-absorbing materials, in particular to a method for preparing MnO2A method for preparing a @ porous carbon composite wave-absorbing material.
Background
With the continuous development of electromagnetic wave technology, novel wave-absorbing materials gradually develop towards light weight, thin thickness, wide frequency band and strong absorption, and in recent years, carbon-based materials have attracted extensive attention as light wave-absorbing materials due to the advantages of small carbon material density, strong electromagnetic attenuation capacity and the like. The metal organic framework compound Mn-MOF-74 has high thermal stability, and in addition, has the advantages of large specific surface area, high porosity, simple preparation process and the like, is suitable for batch production, and the carbon material obtained by adopting the metal organic framework compound Mn-MOF-74 as a precursor has good graphitization property and has important conditions for developing a light microwave absorbing material.
MnO2The product has natural abundance, low cost and environmental compatibility, and can be widely applied to the fields of super capacitors, lithium ion batteries, wastewater treatment, molecular/ionic sieves, catalysts and the like. In particular, MnO2As a typical transition metal oxide, has excellent dielectric properties and chemical stability. These properties contribute to promotion of dielectric loss, further improving absorption efficiency. Prepared cotton cloth @ MnO by che Tan super et al2The composite material has a maximum Reflection Loss (RL) of-53.2 dB at 5.4GHz, a bandwidth of 5.84GHz with RL less than or equal to-10 dB, and a thickness of only 2.0mm (X.Li, L.Wang, W.B.you, L.S.xing, L.T.Yang, X.F.Yu, J.Zhang, Y.S.Li, R.C.Che, Enhanced polarization from flexible resonant MnO2arrays on cotton button with excellent microwave absorption, Nanoscale 11(2019): 13269-. Manganese dioxide/iron trioxide/polyaniline (MnO) prepared by chenchen macrolon et al2/Fe2O3/PANI) composite material, MnO when the coating thickness is 2.5mm2/Fe2O3The maximum reflection loss of PANI at 9.6GHz is-43.22 dB, and the bandwidth with the reflection loss less than-10 dB is 3.44GHz (Wangsheng, Wanglong, Zhuyanting, Liu Zheng Feng, Wan Lei, manganese dioxide/ferric oxide/polyaniline composite material preparation and microwave absorption performance research, novel chemical materials, 2017, 45, 6, 76-79). But for the MnO mentioned above2The composite wave-absorbing material has the defect that the composite material only has one strong absorption peak.
Disclosure of Invention
The invention aims to solve the problems that: provides a method for preparing MnO2The method of the @ porous carbon composite wave-absorbing material can solve the problems of high equipment requirement, high cost and single microwave absorption response frequency band of the existing carbon-based microwave absorbing material.
The technical scheme provided by the invention for solving the problems is as follows: preparation of MnO2A method of a @ porous carbon composite wave-absorbing material, the method comprising the steps of:
Preferably, the molar ratio of the manganese chloride tetrahydrate to the 2, 5-dihydroxyterephthalic acid is (3.2-3.4): 1; the ratio of the volume of the deionized water to the amount of the 2, 5-dihydroxyterephthalic acid substance is (2 mL-4 mL):1 mmol. .
Preferably, the ratio of the volume of the ethanol to the volume of the deionized water is (0.8-1.2): 1.
Preferably, the ratio of the volume of the DMF to the volume of the deionized water is (14-16): 1.
Preferably, the mass ratio of the potassium permanganate to the MnO @ NPC is (1.5-1.7): 1.
Preferably, the ratio of the volume of the hydrochloric acid to the mass of MnO @ NPC is (4 mL-6 mL):0.1 g.
Preferably, the ratio of the volume of the deionized water to the volume of the hydrochloric acid is (1.8-2.2): 1.
Preferably, the heat preservation temperature in the step 1 is 120-150 ℃, and the heat preservation time is 24-26 h; the vacuum drying temperature is 55-65 ℃.
Preferably, the roasting in the step 2 is to heat the mixture from room temperature to 700-800 ℃ under the condition that the heating rate is 2-5 ℃/min and roast the mixture for 2-3 h.
Preferably, the heat preservation temperature in the step 3 is 170-190 ℃, and the heat preservation time is 2-4 h; the vacuum drying temperature is 55-65 ℃.
Compared with the prior art, the invention has the advantages that: the invention selects Mn-MOF-74 as a precursor, and synthesizes the MnO @ NPC composite material by calcining. Oxidation of MnO to MnO by in situ redox reaction2Successfully prepare MnO2@ NPC composite wave-absorbing material; preparation of MnO in accordance with the present invention2The method of the @ NPC composite wave-absorbing material is to combine pyrolysis Mn-MOF-74 with in-situ redox reaction, achieve the purpose of changing the graphitization degree of carbon by changing the calcination temperature, and introduce semiconductor MnO by in-situ redox2And further regulate impedance matching. The obtained composite wave-absorbing material is matched with paraffin to reflect excellent light microwave absorption performance under the condition of a low coating thickness, and extremely strong microwave absorption response of full frequency bands is obtained; through the adjustment of the thickness, more than 90% of wave-absorbing efficiency can be obtained in the full frequency band; compared with the existing carbon-based microwave absorbing material, the preparation method has the problems of high equipment requirement, high cost and single microwave absorbing response frequency band, has the advantages of simple process, low production cost, simple and convenient subsequent treatment, no need of complex synthesis equipment and extremely strong microwave absorbing response of full frequency band, and is suitable for industrial large-scale production.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.
FIG. 1 is an X-ray diffraction pattern;
FIG. 2 is an SEM picture of Mn-MOF-74 prepared in step 1 of example 2;
FIG. 3 is an SEM picture of MnO @ NPC prepared in step 2 of example 2;
FIG. 4 shows MnO prepared in step 3 of example 22SEM pictures of @ NPC;
FIG. 5 is a reflection loss spectrum of the MnO @ NPC composite wave-absorbing material prepared in example 2;
FIG. 6 shows MnO prepared in example 22The reflection loss spectrum of the @ NPC composite wave-absorbing material;
FIG. 7 shows MnO prepared in example 22The effective bandwidth of the @ NPC composite wave-absorbing material under different thicknesses is set;
Detailed Description
The embodiments of the present invention will be described in detail with reference to the accompanying drawings and examples, so that how to implement the technical means for solving the technical problems and achieving the technical effects of the present invention can be fully understood and implemented.
Example 1: the invention has the following specific implementation steps:
and 2, heating the Mn-MOF-74 rod-shaped crystal prepared in the step 1 from room temperature to 700 ℃ under the conditions of nitrogen atmosphere and heating rate of 2 ℃/min, roasting for 2h, and naturally cooling to room temperature under the nitrogen atmosphere to obtain MnO @ NPC.
Example 2: the present embodiment differs from embodiment 1 in that: in the step 2, the Mn-MOF-74 rod-shaped crystal prepared in the step 1 is heated to 800 ℃ from room temperature under the conditions of nitrogen atmosphere and heating rate of 2 ℃/min and is roasted for 2h, and the crystal is naturally cooled to room temperature under the nitrogen atmosphere. The rest is the same as in example 1.
FIG. 1 is an X-ray diffraction pattern and the products of pyrolysis of Mn-MOF-74 at 700 ℃ and 800 ℃ are labeled MnO @ NPC-700 and MnO @ NPC-800, respectively. The oxidation products of MnO @ NPC-700 and MnO @ NPC-800 are labeled as MnO, respectively2@ NPC-700 and MnO2@ NPC-800. As can be seen from FIG. 1, MnO @ NPC-700 and MnO @ NPC-800 show five different peaks at 34.9 °, 40.5 °, 58.7 °, 70.2 ° and 73.8 °, corresponding to the (111), (200), (220), (311) and (222) crystal planes of MnO (PDF #07-0230), respectively. MnO2@ NPC-700 and MnO2The XRD patterns of @ NPC-800 are also similar, showing nine distinct peaks at 28.7 °, 37.3 °, 41.0 °, 42.8 °, 56.7 °, 59.4 °, 64.8 °, 67.2 ° and 68.5 °, corresponding to MnO, respectively2(PDF #24-0735) having (110), (101), (200), (111), (211), (220), (002), (310) and (221) crystal planes.
FIG. 2 is an SEM picture of Mn-MOF-74 prepared in step 1 of example 2. it can be seen from FIG. 2 that the Mn-MOF-74 crystals prepared in example 2 have a rod-like shape.
FIG. 3 is an SEM picture of MnO @ NPC-800 prepared in step 2 of example 2. from FIG. 3, it can be seen that the porous carbon composite absorbing material inlaid with MnO substantially maintains a rod-like structure, but has some gaps, so that the shape of the MnO @ NPC-800 sample looks like a caterpillar.
FIG. 4 shows MnO prepared in step 3 of example 22SEM photograph of @ NPC-800, from FIG. 4 it can be seen that MnO was generated after the redox reaction2The @ NPC-800 sample exhibited a hedgehog-like structure.
FIG. 5 is a reflection loss spectrum of the MnO @ NPC-800 composite wave-absorbing material prepared in example 2, and as can be seen from FIG. 5, the MnO @ NPC-800 shows a good low-frequency wave-absorbing effect, the optimal RL value can reach-54.38 dB when the frequency is 5.12GHz and the matching thickness is 4.48mm, and the frequency bandwidth with the RL smaller than-10 dB is 1.52 GHz.
FIG. 6 shows MnO prepared in example 22The reflection loss spectrum of the @ NPC-800 composite wave-absorbing material can be seen from figure 6, MnO2The @ NPC-800 has the best wave-absorbing performance, the frequency is 12.48GHz, the matching thickness is 2.05mm, the optimal RL value can reach-63.21 dB, and the frequency bandwidth with the RL being less than-10 dB is 4.04 GHz. In addition, the sample also has extremely strong microwave absorption response performance of the full frequency band: the RL maxima at S, C, X and Ku bands were-51.43 dB, -57.22dB, -54.96dB and-63.21 dB, respectively.
FIG. 7 shows MnO prepared in example 22The effective bandwidth of the @ NPC composite wave-absorbing material under different thicknesses can be seen from figure 7, and the wave-absorbing efficiency of more than 90% can be obtained in a full frequency band through the adjustment of the thickness.
The foregoing is merely illustrative of the preferred embodiments of the present invention and is not to be construed as limiting the claims. The present invention is not limited to the above embodiments, and the specific structure thereof is allowed to vary. All changes which come within the scope of the invention as defined by the independent claims are intended to be embraced therein.
Claims (10)
1. Preparation of MnO2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the method comprises the following steps of,
step 1, dissolving manganese chloride tetrahydrate and 2, 5-dihydroxy terephthalic acid into a mixed solution of DMF (dimethyl formamide), deionized water and ethanol, transferring the mixed solution into an autoclave, preserving heat, and centrifugally washing an obtained product for three times by using DMF; finally, placing the obtained product in a vacuum oven for vacuum drying to obtain Mn-MOF-74 rod-shaped crystals;
step 2, roasting the Mn-MOF-74 rod-shaped crystal prepared in the step 1 in a nitrogen atmosphere, and naturally cooling to room temperature in the nitrogen atmosphere to obtain MnO @ NPC;
step 3, dissolving MnO @ NPC and potassium permanganate prepared in the step 2 and 1.0M hydrochloric acid into deionized water, transferring the deionized water into a high-pressure kettle, and keeping the temperature, wherein the obtained product is alternately washed with deionized water and absolute ethyl alcohol for three times; finally, the mixture is placed in a vacuum oven to be dried under the vacuum condition to obtain MnO2@ NPC composite wave-absorbing material.
2. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the molar ratio of the manganese chloride tetrahydrate to the 2, 5-dihydroxy terephthalic acid is (3.2-3.4): 1; the ratio of the volume of the deionized water to the amount of the 2, 5-dihydroxyterephthalic acid substance is (2 mL-4 mL):1 mmol.
3. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the volume ratio of the ethanol to the deionized water is (0.8-1.2): 1.
4. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the ratio of the volume of the DMF to the volume of the deionized water is (14-16): 1.
5. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the mass ratio of the potassium permanganate to the MnO @ NPC is (1.5-1.7): 1.
6. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the ratio of the volume of the hydrochloric acid to the mass of MnO @ NPC is (4 mL-6 mL):0.1 g.
7. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the ratio of the volume of the deionized water to the volume of the hydrochloric acid is (1.8-2.2): 1.
8. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the heat preservation temperature in the step 1 is 120-150 ℃, and the heat preservation time is 24-26 h; the vacuum drying temperature is 55 DEG C～65℃。
9. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the roasting in the step 2 is specifically to heat the mixture from room temperature to 700-800 ℃ under the condition that the heating rate is 2-5 ℃/min and roast the mixture for 2-3 h.
10. The method of claim 1, wherein said MnO is prepared2The method for preparing the @ porous carbon composite wave-absorbing material is characterized by comprising the following steps: the heat preservation temperature in the step 3 is 170-190 ℃, and the heat preservation time is 2-4 h; the vacuum drying temperature is 55-65 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011353123.5A CN112499685B (en) | 2020-11-26 | 2020-11-26 | Preparation of MnO 2 Method for preparing @ porous carbon composite wave-absorbing material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011353123.5A CN112499685B (en) | 2020-11-26 | 2020-11-26 | Preparation of MnO 2 Method for preparing @ porous carbon composite wave-absorbing material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112499685A true CN112499685A (en) | 2021-03-16 |
| CN112499685B CN112499685B (en) | 2023-02-10 |
Family
ID=74966591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011353123.5A Active CN112499685B (en) | 2020-11-26 | 2020-11-26 | Preparation of MnO 2 Method for preparing @ porous carbon composite wave-absorbing material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112499685B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113747777A (en) * | 2021-09-08 | 2021-12-03 | 济南市中恒光机电技术中心 | Electromagnetic wave shielding material |
| CN114433073A (en) * | 2021-12-29 | 2022-05-06 | 广东省科学院化工研究所 | Manganese-based catalyst and preparation method and application thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104229768A (en) * | 2014-07-01 | 2014-12-24 | 江西师范大学 | Porous carbon method with three-dimensional structure |
| CN105932291A (en) * | 2016-06-14 | 2016-09-07 | 华南师范大学 | Method for preparing porous carbon material by taking metal organic framework as template, and application thereof |
| CN108940304A (en) * | 2018-07-27 | 2018-12-07 | 华南理工大学 | A kind of Mn/Ce/Cu base low-temperature plasma body catalyst and preparation and application |
| CN111675242A (en) * | 2020-06-18 | 2020-09-18 | 浙江倪阮新材料有限公司 | Hollow honeycomb flower-shaped manganese dioxide material |
-
2020
- 2020-11-26 CN CN202011353123.5A patent/CN112499685B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104229768A (en) * | 2014-07-01 | 2014-12-24 | 江西师范大学 | Porous carbon method with three-dimensional structure |
| CN105932291A (en) * | 2016-06-14 | 2016-09-07 | 华南师范大学 | Method for preparing porous carbon material by taking metal organic framework as template, and application thereof |
| CN108940304A (en) * | 2018-07-27 | 2018-12-07 | 华南理工大学 | A kind of Mn/Ce/Cu base low-temperature plasma body catalyst and preparation and application |
| CN111675242A (en) * | 2020-06-18 | 2020-09-18 | 浙江倪阮新材料有限公司 | Hollow honeycomb flower-shaped manganese dioxide material |
Non-Patent Citations (5)
| Title |
|---|
| 常照荣 等: ""湿法制备纳米二氧化锰及其电化学性能的研究"", 《河南师范大学学报 (自然科学版)》 * |
| 李志华 等: "双金属功能化的 MOF-74 合成及气体吸附性能", 《无机化学学报》 * |
| 王录才，王芳: "《泡沫金属制备、性能及应用》", 31 October 2012, 国防工业出版社 * |
| 胡丽娟: "《化学分析技术》", 30 September 2018, 延边大学出版社 * |
| 苏秀娟: "《锰及其化合物微波吸收性能研究》", 《冶矿工程》 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113747777A (en) * | 2021-09-08 | 2021-12-03 | 济南市中恒光机电技术中心 | Electromagnetic wave shielding material |
| CN113747777B (en) * | 2021-09-08 | 2022-04-08 | 北京伊斯普电子技术有限公司 | Electromagnetic wave shielding material |
| CN114433073A (en) * | 2021-12-29 | 2022-05-06 | 广东省科学院化工研究所 | Manganese-based catalyst and preparation method and application thereof |
| CN114433073B (en) * | 2021-12-29 | 2023-12-05 | 广东省科学院化工研究所 | Manganese-based catalyst and preparation method and application thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112499685B (en) | 2023-02-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109705808B (en) | Cobalt-nickel alloy-porous carbon composite wave-absorbing material with MOF structure and preparation method thereof | |
| CN109233740B (en) | Method for preparing Fe/Co/C composite wave-absorbing material based on modified MOF material pyrolysis | |
| CN108034408B (en) | Preparation method of graphene-based composite wave-absorbing material | |
| CN112499685B (en) | Preparation of MnO 2 Method for preparing @ porous carbon composite wave-absorbing material | |
| CN108997971B (en) | Preparation method of ZIF-67 reduced graphene oxide-based wave-absorbing composite material CoC-rGo | |
| CN112961650A (en) | Tri-metal organic framework derived iron-nickel alloy/porous carbon ultrathin wave absorber and preparation method thereof | |
| CN108190876B (en) | A kind of graphene composite absorber and preparation method thereof | |
| CN111218112A (en) | rGO/polyimide composite aerogel and preparation method and application thereof | |
| CN112980390B (en) | Preparation method of bimetal organic framework derived magnetic carbon composite wave-absorbing material | |
| CN111137874B (en) | Method for preparing composite wave-absorbing material by taking HKUST-1 as template | |
| CN110746931B (en) | Method for preparing ITO/porous carbon composite wave-absorbing material by taking In-MOFs as template | |
| CN111014711B (en) | Porous napped NiFe/C/Na2MoO4Composite wave-absorbing material and preparation method thereof | |
| CN115074086A (en) | Zn-MOFs derived ZnO/C/Ti 3 C 2 Composite wave-absorbing material and preparation method thereof | |
| CN111484080A (en) | Neodymium-doped praseodymium-manganese oxide wave-absorbing powder material and preparation method thereof | |
| CN112280533B (en) | Preparation method of ternary composite wave-absorbing material with hollow structure | |
| CN115318210B (en) | Preparation method and application of cobalt disulfide/porous carbon/silicon carbide aerogel composite material for electromagnetic shielding | |
| CN113511687B (en) | Wave-absorbing material and preparation method thereof | |
| CN113697795A (en) | Fe carrier of sorghum stalk core3C/C composite wave-absorbing material and preparation method thereof | |
| CN113426386A (en) | Graphene-ferrite composite aerogel wave-absorbing material and preparation method thereof | |
| CN111874888A (en) | Preparation method of ultra-wideband wave absorber of micron-scale square carbon material | |
| CN114875391B (en) | Preparation method of FeCo alloy coated foam nickel wave-absorbing material | |
| CN115785905B (en) | MOF derived carbon-based wave-absorbing material with low calcination temperature, and preparation method and application thereof | |
| CN112292016B (en) | Preparation method of rare earth composite wave-absorbing material | |
| CN111205106B (en) | Silicon nitride @ carbon wave-absorbing foam and preparation method and application thereof | |
| CN114554822B (en) | Composite wave-absorbing film material and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |