核壳型Fe_3O_4/C纳米颗粒的溶剂热法制备及其微波吸收性能

Solvothermal Synthesis and Microwave Absorption Properties of Fe_3O_4/C Core/Shell Nanoparticles

本文以二茂铁为主要原料,通过溶剂热法在190℃反应72h制备了核壳型Fe3O4/C磁性纳米颗粒。通过X-射线衍射仪(XRD)、扫描电子显微镜(SEM)、X-射线能谱仪(EDS)、透射电子显微镜(TEM)、振动样品磁强计(VSM)、矢量网络分析仪对产物进行了表征。结果表明,产物为球形核壳结构的Fe3O4/C纳米颗粒,其尺寸在100~150nm之间,其中碳壳的厚度在10~20nm之间。室温下,产物的矫顽力(Hc)为13.635Oe,剩余磁化率(Mr)为5.00725emu/g,饱和磁化率(Ms)为17.6863emu/g。在2~18GHz范围内,产物厚度为5mm、频率为12.99GHz时,产物的微波反射率为-37.85dB。

Fe3O4/C core/shell nanoparticles were synthesized by solvent-thermal method at the temperature of 190℃for 72hours.The products were characterized by X-ray Diffractometer(XRD),scanning electron microsopy(SEM),energy dispersive spectrometry(EDS),transmission electron microscopy(TEM), vibrating sample magnetometer(VSM)and microwave network analyzer.The electromagnetic characteristics of Fe3O4/C core/shell nanoparticles were measured in the band of 2~18GHz.The results show that Fe3O4/C core/shell nanoparticles have spherical structure.The average diameter of the Fe3O4/C core/shell nanoparticles is between 100nm and 150nm,within which carbon shell is between 10nm and 20nm.The magnetic susceptibility meets about linearly with the applied magnetic field at room temperature,and the coercivity(Hc),remanent magnetization(Mr),and the saturation magnetization(Ms)values of the product at room temperature are 13.635Oe,5.00725emu/g and 17.6863emu/g,respectively.The reflectivity peak reaches-37.85dB at 12.99GHz for the composite with a thickness of 5mm,and the absorption bandwidth with the reflection loss below-8dB up to 4.8GHz for the composite with the thickness of 2-5mm.