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CN-116463105-B - Preparation method of diamond dodecahedron cavity structure electromagnetic wave absorbent Fe/ZnO@C

CN116463105BCN 116463105 BCN116463105 BCN 116463105BCN-116463105-B

Abstract

The invention discloses a preparation method of an electromagnetic wave absorber Fe/ZnO@C with a rhombic dodecahedron cavity structure, which belongs to the technical field of composite materials and comprises the steps of firstly synthesizing magnetic Fe 3 O 4 particles, further preparing a precursor Fe 3 O 4 @ZIF-8, coating polydopamine on the surface of the precursor Fe 3 O 4 @ZIF-8@PDA to obtain Fe 3 O 4 @ZIF-8@PDA, and finally obtaining a rhombic carbon shell coated zinc-iron alloy through high-temperature carbonization treatment. The Fe/ZnO@C compound with the rhombic dodecahedron cavity structure prepared by the method has excellent electromagnetic wave absorption performance. The invention has simple preparation process, is suitable for large-scale production, has novel material structure, relatively small density and excellent product performance.

Inventors

  • QIU HONGFANG
  • PENG JIAN
  • CHEN GUIYONG
  • LIU ZHIJIE
  • ZHENG LIHENG
  • LIU SITONG

Assignees

  • 成都飞机工业（集团）有限责任公司

Dates

Publication Date
20260512
Application Date
20230421

Claims (12)

  1. 1. The preparation method of the electromagnetic wave absorber Fe/ZnO@C with the rhombic dodecahedron cavity structure is characterized by comprising the steps of synthesizing a methanol solution of magnetic Fe 3 O 4 particles, preparing a precursor Fe 3 O 4 /ZIF-8, coating polydopamine on the surface of the precursor Fe 3 O 4 /ZIF-8 to obtain an intermediate Fe 3 O 4 /ZIF-8@PDA, and performing high-temperature carbonization treatment to obtain the electromagnetic wave absorber Fe/ZnO@C with the rhombic dodecahedron cavity structure; The preparation method of precursor Fe 3 O 4 /ZIF-8 comprises diluting 1-5mL of methanol solution of magnetic Fe 3 O 4 particles with methanol to 40mL, adding 0.6g PVP, and dripping Zn (NO) 3 ) 2 6H 2 O and 2-methylimidazole DMI, stirring ultrasonically and standing, filtering the obtained product, washing and drying.
  2. 2. The method of claim 1, wherein the step of preparing the methanol solution of the magnetic Fe 3 O 4 particles comprises the steps of mixing FeCl 3 6H 2 O、NaHCO 3 are respectively dissolved in deionized water, L-ascorbic acid is added after mixing, the obtained mixed solution is placed in a reaction kettle after ultrasonic treatment, the hydrothermal reaction is carried out at 80-140 ℃ for 2-8H, the obtained solution is cooled, washed, filtered and dispersed in methanol solution.
  3. 3. The process according to claim 2, wherein FeCl 3 The molar ratio of 6H 2 O to NaHCO 3 is 1:2-4, feCl 3 The molar ratio of 6H 2 O to L-ascorbic acid is 1:0.1-0.2.
  4. 4. The method according to claim 1, wherein Zn (NO 3 ) 2 The mass ratio of 6H 2 O to 2-methylimidazole DMI is 1:1-4.
  5. 5. The preparation method of the intermediate Fe 3 O 4 /ZIF-8@PDA according to claim 1, wherein the preparation process comprises the steps of dispersing the prepared precursor Fe 3 O 4 /ZIF-8 in deionized water by ultrasonic, respectively adding dopamine hydrochloride and 3-hydroxymethyl aminomethane THAM, stirring, washing the obtained product with water, filtering and drying.
  6. 6. The preparation method according to claim 1 or 5, wherein the preparation process of Fe/ZnO@C comprises the steps of placing the prepared intermediate Fe 3 O 4 /ZIF-8@PDA in a tube furnace, and calcining at high temperature under argon atmosphere to obtain Fe/ZnO@C.
  7. 7. The preparation method according to claim 2, wherein the hydrothermal reaction temperature is 120 ℃ and the reaction time is 6 hours.
  8. 8. The preparation method according to claim 5, wherein the mass ratio of the precursor Fe 3 O 4 /ZIF-8 to the dopamine hydrochloride is 1:2-6, and the mass ratio of the dopamine hydrochloride to the 3-hydroxymethyl aminomethane THAM is 1:0.5-2.
  9. 9. The process of claim 6, wherein the intermediate Fe 3 O 4 /ZIF-8@PDA is calcined at a temperature of 500-800 ℃ for a calcination time of 1-6 h.
  10. 10. The method according to claim 4, wherein 2mLFe 3 O 4 of methanol solution is diluted to 40mL 3 ) 2 6H 2 O concentration was 0.05g/mL methanol, zn (NO 3 ) 2 The mass ratio of 6H 2 O to 2-methylimidazole DMI is 1:1.5.
  11. 11. The preparation method according to claim 8, wherein the mass ratio of the precursor Fe 3 O 4 /ZIF-8 to the dopamine hydrochloride is 1:4, and the mass ratio of the dopamine hydrochloride to the 3-hydroxymethyl aminomethane THAM is 1:1.
  12. 12. The method according to claim 6, wherein the intermediate Fe 3 O 4 /ZIF-8@PDA has a calcination temperature of 700 ℃ and a calcination time of 2 h.

Description

Preparation method of diamond dodecahedron cavity structure electromagnetic wave absorbent Fe/ZnO@C Technical Field The invention relates to the technical field of composite materials, in particular to a preparation method of an electromagnetic wave absorbent Fe/ZnO@C with a rhombic dodecahedron cavity structure. Background The high-speed development of electronic technology brings great convenience to our daily life and brings a great deal of electromagnetic pollution. Electromagnetic pollution has become another important pollution source after atmospheric pollution, water pollution and noise pollution, and excessive electromagnetic radiation seriously affects the physical and mental health of human beings. In modern war, radar detection technology is increasingly enhanced, and the demand of ships, warplanes and the like for higher wave-absorbing stealth capability is stimulated. Therefore, development of efficient electromagnetic wave absorbing materials to adapt to harsher battlefield environments becomes a hotspot of military national defense of various countries. Because the single-component magnetic metal material has the defects of narrow absorption bandwidth, high density, low absorption strength, easy corrosion and the like, the current requirements are difficult to meet, and therefore, the preparation of the multi-component composite wave absorber becomes a mainstream research direction. The Fe/ZnO@C is used as an electromagnetic wave absorber with a diamond dodecahedron cavity with a special structure, the outer carbon shell is favorable for protecting inner metal components and dielectric loss, the middle cavity can reduce the density of the material, the ZnO is used as a high dielectric material to provide dielectric loss, the Fe provides magnetic loss, and the ternary components cooperate to enable the material to have a good electromagnetic wave absorption effect. Disclosure of Invention The invention provides a preparation method of an electromagnetic wave absorber Fe/ZnO@C with a rhombic dodecahedron cavity structure, which has simple preparation process and good electromagnetic wave absorption performance of a finished product. In order to achieve the above object, the present invention has the following technical scheme: The preparation method of the electromagnetic wave absorbent Fe/ZnO@C with the rhombic dodecahedron cavity structure comprises the steps of synthesizing magnetic Fe 3O4 particles, preparing a precursor Fe 3O4/ZIF-8, coating polydopamine on the surface of the precursor Fe 3O4 @ZIF-8 to obtain an intermediate Fe3O4@ZIF-8@PDA, and performing high-temperature carbonization treatment to obtain the rhombic carbon-shell coated zinc-iron alloy Fe/ZnO@C. In one embodiment, the preparation process of the Fe 3O4 particles comprises the steps of respectively dissolving FeCl 3∙6H2O、NaHCO3 in deionized water, adding L-ascorbic acid after mixing, placing the obtained mixed solution in a reaction kettle after ultrasonic treatment, performing hydrothermal reaction at 80-140 ℃ for 2-8 h, cooling the obtained solution, washing, and filtering to disperse in methanol solution. In one embodiment, the molar ratio of FeCl 3∙6H2 O to NaHCO 3 is 1:2-4 and the molar ratio of FeCl 3∙6H2 O to L-ascorbic acid is 1:0.1-0.2. In one embodiment, the precursor Fe 3O4/ZIF-8 is prepared by diluting 1-5mL of the above-mentioned methanol solution of Fe 3O4 with methanol to 40mL, adding 0.6g PVP, respectively dropping methanol solution of Zn (NO 3)2∙6H2 O) and 2-methylimidazole (DMI), ultrasonic stirring, standing, filtering, washing, and oven drying. In one embodiment, the mass ratio of Zn (NO 3)2∙6H2 O) to 2-methylimidazole (DMI) is 1:1-4. In one embodiment, the preparation process of the intermediate Fe 3O4/ZIF-8@PDA comprises the steps of ultrasonically dispersing the prepared precursor Fe 3O4/ZIF-8 in deionized water, respectively adding dopamine hydrochloride and 3-hydroxymethyl aminomethane (THAM), stirring, washing the obtained product with water, filtering and drying. In one embodiment, the preparation process of the Fe/ZnO@C comprises the steps of placing the prepared intermediate Fe 3O4/ZIF-8@PDA in a tube furnace, and calcining at high temperature in an argon atmosphere to obtain the Fe/ZnO@C. In one embodiment, the hydrothermal reaction temperature is 120 ℃ and the reaction time is 6 hours. In one embodiment, the mass ratio of Fe 3O4/ZIF-8 to dopamine hydrochloride is 1:2-6, and the mass ratio of dopamine hydrochloride to 3-hydroxymethyl aminomethane (THAM) is 1:0.5-2. In one embodiment, the intermediate Fe 3O4/ZIF-8@PDA is calcined at a temperature of 500-800 ℃ for a calcination time of 1-6 h. In one embodiment, 2mLFe 3O4 of methanol solution is diluted to 40mL, zn (NO 3)2∙6H2 O concentration is 0.05g/mL methanol, zn (NO 3)2∙6H2 O to 2-methylimidazole (DMI) mass ratio is 1:1.5). In one embodiment, the mass ratio of Fe 3O4/ZIF-8 to dopamine hydrochloride is 1:4, and the mass ratio of dopamine hydr