CN-121975399-A - Fe-B MBene-RGO wave-absorbing corrosion-preventing integrated coating, preparation method and application

Abstract

The invention belongs to the technical field of functional composite materials, and particularly relates to an Fe-B MBene-RGO wave-absorbing and corrosion-preventing integrated coating, a preparation method and application. The method aims to solve the dual technical bottlenecks of wave-absorbing efficiency attenuation and corrosion prevention function failure caused by single electromagnetic loss mechanism, weak interface combination and easy structural degradation of the existing wave-absorbing material in corrosive service environments such as ocean high humidity and high salt, industrial acid rain and the like. The technical scheme includes that the method comprises the steps of preparing a working electrode after pickling Fe 2 AlB 2 powder, selectively removing aluminum element through electrochemical etching to obtain Fe-B MBene with positively charged surface, carrying out amination modification on Fe-B MBene to maintain positive electricity, carrying out electrostatic attraction self-assembly and reduction on modified Fe-B MBene and graphene oxide to form a composite material, dispersing the composite material in an epoxy resin system, coating a metal substrate, and solidifying the metal substrate to form a film to construct an integrated functional coating.

Inventors

• HOU HONGBO
• MENG FANBIN
• Xiong Changfeng
• YANG QIAN
• LI TIAN
• OU YANG
• YI SHUN
• ZOU YAO

Assignees

• 西南交通大学

Dates

Publication Date

20260505

Application Date

20260323

Claims (10)

1. 1. The preparation method of the Fe-B MBene-RGO wave-absorbing and corrosion-preventing integrated coating is characterized by comprising the following steps of: Step 1, pickling Fe 2 AlB 2 powder with hydrochloric acid solution, washing and drying, mixing with superconductive carbon black and polyvinylidene fluoride, coating on the surface of a foam nickel screen, and drying to obtain a working electrode; Step 2, using the working electrode as a working electrode, adopting a three-electrode system, and carrying out electrochemical etching in 5-25 wt% sodium hydroxide aqueous solution at 70 ℃ and with a current density of 0.5 mA cm -2 , and selectively removing Al element to obtain Fe-B MBene with positively charged surface; step 3, dispersing the Fe-B MBene in an ethanol/water mixed solution, and adding 3-aminopropyl trimethoxy silane for amination modification to ensure that the surface maintains positive electricity; Mixing amination modified Fe-B MBene and graphene oxide in a water phase, utilizing electrostatic attraction of positive and negative charges to realize self-assembly, and reducing the graphene oxide by sodium ascorbate to obtain a Fe-B MBene/RGO composite material, wherein the mass fraction of the graphene oxide relative to Fe-B MBene is 0.5-2.5 wt%; And 5, dispersing Fe-B MBene/RGO in an epoxy resin matrix, coating the matrix on the surface of a metal substrate, and curing to obtain the wave-absorbing corrosion-resistant integrated coating.
2. 2. The method of claim 1, wherein the washing in step 1 is three times with deionized water; the drying is carried out for 12 hours at 40 ℃ in vacuum; The mass ratio of the superconducting carbon black to the polyvinylidene fluoride to the Fe 2 AlB 2 powder is 6:3:20, and the drying is carried out for 6 hours at 50 ℃.
3. 3. The preparation method of the three-electrode system according to claim 1, wherein in the step 2, the counter electrode of the three-electrode system is a platinum sheet, the reference electrode is Ag/AgCl, after etching is finished, the working electrode is placed in N-methylpyrrolidone solution for ultrasonic treatment for 30 minutes, etching products are collected through magnetic separation, and the etching products are alternately washed by the N-methylpyrrolidone and deionized water and freeze-dried for 24 hours.
4. 4. The preparation method of claim 1, wherein in the step 3, the volume ratio of the ethanol/water mixed solution is 9:1, the mass ratio of the 3-aminopropyl trimethoxy silane to the Fe-B MBene is 2:1, glacial acetic acid is added in the amination modification process, the use amount of the glacial acetic acid is 4 mL per 150: 150 mL mixed solution, the reaction is stirred at room temperature for 24 hours, and after the reaction is completed, the mixture is collected by magnetic separation and freeze-dried.
5. 5. The preparation method of claim 1, wherein in step 4, after the amination modified Fe-B MBene is mixed with graphene oxide, the mixture is subjected to ultrasonic treatment for 30 minutes and then stirred for 2 hours, the mass ratio of sodium ascorbate to graphene oxide is 1:1, the mixture is reduced at 50 ℃ for 2 hours, after the reduction is completed, the mixture is collected through magnetic separation, is alternately washed with absolute ethyl alcohol and deionized water, and is dried at 60 ℃ in vacuum for 12 hours.
6. 6. The method according to any one of claims 1 and 5, wherein in step 4, the mass fraction of the graphene oxide relative to Fe-B MBene is 2: 2 wt%.
7. 7. The method according to claim 1, wherein in step 5, Dispersing the Fe-B MBene/RGO composite material in epoxy resin according to a mass ratio of 1:70, adding a curing agent with a mass ratio of 1:7, coating the surface of a metal substrate, and curing for 72 hours at room temperature to form the wave-absorbing and corrosion-preventing integrated coating.
8. 8. A method according to any one of claims 1 or 3, wherein in step 2, the concentration of the aqueous sodium hydroxide solution is 20 wt%.
9. 9. An integrated Fe-B MBene-RGO wave-absorbing and corrosion-preventing coating, prepared by the method according to any one of claims 1-8.
10. 10. The Fe-B MBene-RGO wave-absorbing corrosion-resistant integrated coating of claim 9 applied to the field of corrosion resistance of 5G/6G communication equipment, radar stealth equipment, and marine engineering structures.

Description

Fe-B MBene-RGO wave-absorbing corrosion-preventing integrated coating, preparation method and application Technical Field The invention belongs to the technical field of functional composite materials, and particularly relates to an Fe-B MBene-RGO wave-absorbing and corrosion-preventing integrated coating, a preparation method and application. Background With the rapid development of modern electronic equipment and communication technology, the electromagnetic environment is increasingly complex, and electromagnetic pollution becomes an important hidden trouble affecting information safety, equipment compatibility and even human health. Particularly in the scenes of 5G/6G communication, radar systems, stealth platforms and the like, the demand for high-efficiency wave-absorbing materials with the characteristics of wide frequency, strong absorption and light weight is urgent. However, practical service environments, such as ocean high humidity and high salt, industrial acid rain or aerospace extreme climates, present serious challenges for the long-term stability of materials, in that conventional wave absorbers tend to fail rapidly due to corrosion, oxidation or structural degradation. The two-dimensional material has wide prospect in the field of electromagnetic wave absorption due to the ultra-large specific surface area, rich interface polarization effect and adjustable electromagnetic parameters. In recent years, new two-dimensional transition metal borides (MBene) have been attracting attention due to their unique strong covalent bond structure of M-B, which is significantly better in chemical and thermodynamic stability than the readily oxidizable MXene. Particularly, the Fe-based MBene prepared from the Fe 2AlB2 precursor not only maintains intrinsic ferromagnetism, but also has certain conductivity, and is expected to realize high-efficiency electromagnetic attenuation through a synergistic mechanism of magnetic loss and dielectric loss, and meanwhile, the structural integrity is maintained in a corrosive environment. However, the Fe-based MBene intrinsic conductive network is insufficient, and it is difficult to construct an efficient electron transport path, which limits the full play of dielectric loss capability. Reduced Graphene Oxide (RGO) has high conductivity and large specific surface area, but single RGO lacks a mechanism of magnetic loss and has limited corrosion resistance. Therefore, development of a compound strategy capable of cooperatively improving conductivity, electromagnetic loss efficiency and structural stability is needed to realize integration of wave-absorbing and corrosion-preventing functions. Disclosure of Invention The invention aims to solve the double technical bottleneck problems of rapid attenuation (low reflection loss and narrow effective bandwidth) and failure of anti-corrosion function (rapid penetration acceleration of corrosive medium and abrupt reduction of impedance value) of the wave absorbing efficiency caused by single electromagnetic loss mechanism, weak interface combination and easy degradation of structure in the corrosive service environment such as ocean high humidity and high salt, industrial acid rain and the like of the existing wave absorbing material (such as limited dielectric loss, lack of magnetic loss mechanism and weak anti-corrosion barrier caused by insufficient single Fe-based MBene conductive network). The invention adopts the following technical means to realize the purposes: the invention provides a preparation method of an Fe-B MBene-RGO wave-absorbing and corrosion-preventing integrated coating, which comprises the following steps: Step 1, treating Fe 2AlB2 powder with 1M hydrochloric acid solution for 30 seconds for pickling, washing and drying, mixing with superconductive carbon black and polyvinylidene fluoride, coating on the surface of a foam nickel screen, and drying to obtain a working electrode; step 2, using the working electrode as a working electrode, adopting a three-electrode system, and carrying out electrochemical etching at 70 ℃ in 5-25 wt% sodium hydroxide aqueous solution and with a current density of 0.5 mA cm < -2 >, and selectively removing Al element to obtain Fe-B MBene with positively charged surface; step 3, dispersing the Fe-B MBene in an ethanol/water mixed solution, and adding 3-aminopropyl trimethoxy silane for amination modification to ensure that the surface maintains positive electricity; Mixing amination modified Fe-B MBene and graphene oxide in a water phase, utilizing electrostatic attraction of positive and negative charges to realize self-assembly, and reducing the graphene oxide by sodium ascorbate to obtain a Fe-B MBene/RGO composite material, wherein the mass fraction of the graphene oxide relative to Fe-B MBene is 0.5-2.5 wt%; and 5, dispersing the Fe-B MBene/RGO composite material in epoxy resin according to a mass ratio of 1:70, adding a curing agent with a mass ratio of 1:7, coating the e