Preparation method of nano-barium titanate/iron tetroxide hybrid material with high wave-absorbing performance

Abstract

The invention relates to a method for preparing a nano-barium titanate / ferric oxide hybrid material with high wave-absorbing performance. In this method, nano-Fe 3 o 4 Particles were directly deposited in situ on nano-BaTiO 3 Form hybrid material powder on the surface, nano-Fe 3 o 4 In nano BaTiO 3 The surface forms a surface contact, resulting in a large number of interfaces. Due to the accumulation of a large number of defects and ions on both sides of the interface, an electromagnetic wave barrier is formed, which strongly absorbs and scatters electromagnetic waves in various frequency bands. These hybrid materials after powder molding have high electrical loss and magnetic loss. At 20Hz-3GHz, the dielectric constant is 10-1000, and the electrical loss is 0.1-44.3; at 10Hz-1GHz, the magnetic permeability is 3.69-9.5, and the magnetic loss is 6.7-15.9; when the thickness of the hybrid material is 2mm, At 2GHz, the reflection rate is -9.84~-29.4dB, and the absorption rate is 89.62%-99.89%. It has good electromagnetic wave absorption performance, especially suitable for use as a wave absorbing material or electromagnetic shielding material.

Description

Technical field: [0001] The invention belongs to the technical field of preparation of wave-absorbing materials and electromagnetic shielding materials, and in particular relates to a method for preparing a nano barium titanate / ferric oxide hybrid material with high wave-absorbing performance. Background technique: [0002] Absorbing materials refer to a class of materials that can absorb electromagnetic wave energy projected onto its surface, and convert electromagnetic wave energy into heat energy or other forms of energy through the dielectric loss of the material. Generally, it is composed of matrix material and absorbent. According to the absorbing mechanism, absorbing materials can be divided into two types: electric loss type and magnetic loss type: electric loss type absorbing materials mainly absorb and attenuate electromagnetic waves through the electronic polarization, ion polarization and interface polarization of the medium; Lossy absorbing materials mainly abs...

AI Technical Summary

Problems solved by technology

[0003] BaTiO 3 and Fe 3 o 4 All belong to the traditional coating absorbing materials, which have many advantages such as simple preparation method and cheap raw materials, but at the same time they also have disadvantages such as narrow absorption frequency band and low absorption intensity.

BaTiO 3 It is a kind of dielectric material, but the microwave absorption performance of unmodified pure barium titanate is not ideal

Fe 3 o 4 It is a kind of magnetic loss material. Ferrite is a more researched and mature absorbing material. Its advantages are high absorption efficiency, thin coating, and wide frequency band. The disadvantage is that the relative density increases the weight of components. As a result, the overall performance of the components is affected, and the high-frequency effect is not ideal

[0004] Including some of the prior art using piezoelectric properties and electromagnetic wave absorption properties, the BaTiO 3 and Fe 3 o 4 Nanoparticles dispersed into PAN solution to obtain BaTiO 3 / Fe 3 o 4 / PAN spinning liquid, and then carry out electrospinning, and in order to meet the electromagnetic shielding and can be widely used, spinning preparation 1. The cost is too high, the process is unstable, and the needles are easy to block when PAN is mass-produced, and the efficiency is low and not environmentally friendly. 2. The size is large, the particles are unevenly distributed on the silk, and the efficiency is low. 3. The materials prepared by the spinning method need to be sintered, which is easy to cause environmental protection and energy consumption problems

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