摘要
二维碳/氮化物MXene近年来受到了越来越多的关注,其优异的导电性和表面丰富的官能团可对电磁波吸收有着积极的作用.然而作为仅有介电损耗的非磁性材料,MXene存在着阻抗不匹配等问题,极大地限制了实际应用.因此,将磁性材料与MXene结合成为了目前微波吸收领域的研究热点,而降低MXene堆叠现象与调控磁性材料所占比例成为实现良好微波吸收性能的关键因素.本文通过简单的静电吸附作用将水热法制备的Fe_(3)O_(4)纳米微球锚定在大尺寸单层二维Ti_(3)C_(2)T_(x)表面,并在该Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)复合结构中实现了–69.31 dB的最小反射损耗值(频率为16.19 GHz),且此时的双峰吸收带宽可达到3.39 GHz.另外,雷达截面(RCS)模拟计算表明,该样品也具有优异的RCS值,表现出对雷达波优异的衰减能力.本研究对二维材料和磁性材料在微波吸收领域的性能改善与实际应用提供了新的思路.
With the rapid development of electronic equipment,electromagnetic interference and electromagnetic radiation pollution have become serious problems,because excessive electromagnetic interference will not only affect normal operation of electronic equipment but also do great harm to human health.In general,an ideal material for microwave absorption with the characteristics of high reflection loss(RL)intensity,wide effective absorption band(EAB),thin thickness,and lightweight could effectively consume electromagnetic wave(EMW)energy.Therefore,it is crucial to search for such an ideal microwave absorption material to deal with the electromagnetic radiation pollution.Two-dimensional(2D)carbon/nitride MXene has received more and more attention in recent years,because excellent electrical conductivity and rich surface-functional groups in MXene show positive effects on electromagnetic wave absorption.However,as a non-magnetic material with only dielectric loss,MXene exhibits obvious impedance mismatch,which greatly limits its practical applications.Combining MXene with magnetic materials becomes a hotspot for the exploration of ideal microwave absorption materials.As a typical ferrite,Fe_(3)O_(4)shows excellent soft magnetic properties such as high saturation magnetization,high chemical stability,and simple preparation.In this paper,the 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite is successfully prepared by hydrothermal method and simple electrostatic adsorption process.The Fe_(3)O_(4)nanoparticles are uniformly anchored on the surface of large-sized monolayer Ti_(3)C_(2)T_(x),which effectively reduces the stacking of MXene.By regulating the proportion of magnetic materials,the microwave absorption performance of 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite is investigated.With the content of Fe_(3)O_(4)nanoparticles in the 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite increasing from 4 mg to 8 mg,the microwave absorption performance is enhanced obviously.This is caused by the abundant Fe_(3)O_(4)/Ti_(3)C_(2)T_(x)interface,scattering channels,point defect,charge density difference in 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite,and the optimized impedance matching.The minimum reflection loss(RLmin)of 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite reaches–69.31 dB at a frequency of 16.19 GHz,and the effective absorption band(EAB)achieves 3.39 GHz.With the content of Fe_(3)O_(4)nanoparticles further increasing to 10 mg,the microwave absorption performance shows a decreasing trend.Excessive Fe_(3)O_(4)nanoparticles in the 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite lead to the decrease of electrical conductivity and thus the impedance dis-matching and dielectric loss decreasing,which leads the microwave absorption performance to decrease.Radar scattering cross section(RCS)is a physical quantity that evaluates the intensity of the scattered echo energy in the intercepted electromagnetic wave energy.The results of the RCS simulation can be applied to real objects which have been widely utilized in radar wave stealth.Its multi-angle simulation results can be used as an important basis for evaluating the stealth capability of microwave-absorbing material.The RCS simulations show that the average RCS value of 2D Fe_(3)O_(4)@Ti_(3)C_(2)T_(x)composite is over–47.92 dBm^(2)at an incidence angle of 25°,demonstrating its excellent radar wave absorption performance.This study provides new ideas for improving and practically using two-dimensional and magnetic materials in the microwave absorption field and gives a new path to the subsequent development of microwave-absorbing composites.
作者
肖忆瑶
何佳豪
陈南锟
王超
宋宁宁
Xiao Yi-Yao;He Jia-Hao;Chen Nan-Kun;Wang Chao;Song Ning-Ning(College of Mathematics and Physics,Beijing University of Chemical Technology,Beijing 100029,China)
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2023年第21期330-341,共12页
Acta Physica Sinica
基金
国家自然科学基金(批准号:51872021)资助的课题.