Study Of Electromagnetic Characteristic In RGO,ATO,BiOI/Ni@C And Optimized Design Of One-dimensional Photonic Crystal

The rapid development of electronic devices,electrical equipment and 5G techniques has dramatically increased public concerns on electromagnetic pollution and electromagnetic radiation hazards.Microwave absorbing materials(MAMs)are one of the most effective means to reduce electromagnetic pollution,resist electromagnetic interference and eliminate electromagnetic radiation.However,it seems that traditional magnetic-dielectric composite MAMs was trapped by bottle neck in higher microwave absorbing performance and stability due to poor compatibility of absorbing performance and insufficient stability under specific conditions.At the same time,the strength of absorbing performance is restricted by the material structure,and further improvement of the absorbing performance of absorbing materials faces technical challenges.In this study,reduced graphene oxide(RGO)was prepared by hydrothermal reduction method based on the improved Hummers method,Antimony-doped tin dioxide(ATO)was prepared on the basis of the ion-exchange hydrolysis experimental method using isoamyl acetate azeotropic drying method,and Ni@C nanocapsules prepared by the arc plasma method and Bi OI microspheres prepared by the oil bath method were compounded by chemical synthesis to obtain a nano-core-shell structure composite material.And based on the finite element analysis method,we designed a new type of one-dimensional photonic crystal microwave absorbing material,and explored the performance comparison of magnetic-dielectric composite absorbing material and one-dimensional photonic crystal absorbing material,which were depended on multiple microwave absorption mechanisms and complex micromorphological structure comprehensive effect of wave performance.The optimal performance results of RGO and ATO material combination are obtained.According to the comparison between the experimental data and the simulation results,it is shown that obtaining RGO by hydrothermal method without using a reducing agent mainly relies on interfacial polarization and electronic polarization to enhance its dielectric loss.The highly conductive ATO nanoparticles obtained by the azeotropic method have excellent absorbing properties mainly based on dielectric loss.Bi OI/ Ni@C composite nanomaterial with complex microstructure achieves the best reflection loss of-61.35 d B and an excellent bandwidth of 5.86 GHz(11.28?17.14GHz).One-dimensional photonic crystal structure design with ATO and RGO can achieve significant enhancement of microwave absorption performance.which shows excellent a minimal reflection loss of-45.2 d B @ 16.1 GHz,and-10 d B bandwidth of 5.4 GHz.Multi-physics finite element method(FEM)was used to clarify that the root of the excellent absorbing performance of the one-dimensional photonic crystal structure absorbing material lies in the electromagnetic response behavior caused by interfacial polarization,natural resonance and quarter-wave effect.This study possibly give a new technical approach for achieving high-performance electromagnetic absorption materials,which is expected to become a new choice in radar coating preparation and stealth materials.