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Preparation method of a nanometer core-shell microwave absorbing material

A wave-absorbing material and nano-core-shell technology, applied in the field of wave-absorbing materials, can solve problems such as complex preparation and narrow absorption bandwidth, and achieve the effects of simple preparation method, wide wave-absorbing bandwidth and good application prospects

Active Publication Date: 2019-01-25
UNIV OF SCI & TECH BEIJING +1
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] Aiming at the disadvantages of complex preparation of absorbing materials and narrow absorption bandwidth in the prior art, the present invention provides a core-shell structure Fe@C@Co 3 o 4 Preparation method of nanopowder and its application in the field of microwave absorption

Method used

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  • Preparation method of a nanometer core-shell microwave absorbing material
  • Preparation method of a nanometer core-shell microwave absorbing material
  • Preparation method of a nanometer core-shell microwave absorbing material

Examples

Experimental program
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Embodiment 1

[0033] (1) Preparation of precursors

[0034] Add potassium ferricyanide and surfactant PVP K30 with a molar ratio of 4:1 to a hydrochloric acid solution with a concentration of 0.1mol / L, so that the concentration of ferricyanide is 5mmol / L; then react the solution at 80°C Heating in the kettle for 12 hours, centrifuging and drying the obtained solution to obtain nano-powder; using ethanol and water as solvent, the volume ratio is 1:2, adding the dried nano-powder and cobalt chloride in a mass ratio of 2:1 to In the solvent, add surfactant CTAB, the concentration of surfactant CTAB in the solution is 0.1g / ml, add ammonia water, the concentration of ammonia water in the solution is 0.75mol / L, put the mixed solution in an airtight container and keep it at 80°C After heating for 8 hours, the obtained solution was centrifuged and dried to obtain a precursor.

[0035] (2) Heat treatment of the precursor

[0036] The precursor obtained in step (1) was heat-treated in a tube furnac...

Embodiment 2

[0039] (1) Preparation of precursors

[0040] Add potassium ferricyanide and surfactant SDS with a molar ratio of 2:1 to the hydrochloric acid solution with a concentration of 0.1mol / L, so that the concentration of ferricyanide is 5mmol / L; Heating in middle temperature for 12h, centrifuging and drying the obtained solution to obtain nano-powder; using ethanol and water as solvent, adding the dried nano-powder and cobalt chloride to the solvent in a mass ratio of 2:1, adding surfactant CTAB, The concentration of surfactant CTAB in the solution is 0.1g / ml, add ammonia water, the concentration of ammonia water in the solution is 0.75mol / L, put the mixed solution in a closed container and heat it at 80°C for 8h, centrifuge the obtained solution, Dry to obtain the precursor.

[0041] (2) Heat treatment of the precursor

[0042] The precursor obtained in step (1) was heat-treated in a tube furnace filled with nitrogen, firstly at 200°C for 2 hours, then heated to 500°C at a heatin...

Embodiment 3

[0045] (1) Preparation of precursors

[0046] Add potassium ferricyanide and surfactant PVP K15 with a molar ratio of 1:1 to a hydrochloric acid solution with a concentration of 0.2mol / L, so that the concentration of ferricyanide is 5mmol / L; then react the solution at 80°C Heating in the kettle for 12 hours, centrifuging and drying the obtained solution to obtain nano-powder; using ethanol and water as solvents, adding the dried nano-powder and cobalt acetate into the solvent at a mass ratio of 1:1, adding surfactant CTAB, The concentration of surfactant CTAB in the solution is 0.2g / ml, add ammonia water, the concentration of ammonia water in the solution is 1.50mol / L, put the mixed solution in a closed container and heat it at 80°C for 8h, centrifuge the obtained solution, Dry to obtain the precursor.

[0047] (2) Heat treatment of the precursor

[0048] The precursor nano-powder obtained in step (1) was heat-treated in a tube furnace filled with nitrogen, first kept at 200...

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Abstract

A preparation method of nano core-shell microwave absorbing material relates to in-situ obtaining core-shell structure Fe @ C @ Co3O4 nanometer powder by heat treatment of precursor and applying it inmicrowave absorbing field. The invention takes ferricyanide and cobalt salt as raw materials, firstly synthesizes the precursor nano-meter powder with core-shell structure, and secondly heat-treats the precursor to obtain Fe @ C @ Co3O4 nano-meter powder with core-shell structure in situ. The process is not only simple, but also has excellent microwave absorbing properties, especially wide absorption bandwidth, which has a good application prospect.

Description

technical field [0001] The invention relates to a core-shell structure Fe@C@Co 3 o 4 The invention discloses a preparation method of nanometer powder, which belongs to the field of wave-absorbing materials. Background technique [0002] With the acceleration of the informationization process and the intensification of electronic warfare in modern warfare, the performance of absorbing materials [0003] Can make higher and higher demands. The absorbing material has gradually developed from a single high absorption strength to a direction of small volume, light weight, wide frequency band and strong absorption. A single absorber cannot meet the conditions of impedance matching and strong absorption at the same time, which makes composite absorber materials with the properties of two or more materials attract extensive attention. The core-shell structure design concept is applied to the research of electromagnetic wave absorbing materials, and the electromagnetic parameters...

Claims

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Application Information

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IPC IPC(8): H05K9/00C09K3/00
CPCC09K3/00H05K9/0088
Inventor 俞宏英孙冬柏王宁
Owner UNIV OF SCI & TECH BEIJING
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