微波吸收复合材料Ag/NiFe2-xCexO4的制备与表征

用水热法分别制备了镍铁氧体粉末(NiFe2O4)及其单质银复合、Ce^3+掺杂镍铁氧体粉末(Ag/NiFe2-xCexO4)复合物。用粉末X射线衍射仪(XRD)、扫描电子显微镜(SEM)、振动样品磁强计(VSM)和矢量网络分析仪(VAN)等分别表征了产物的结构、形貌、电磁性能。结果表明,水热法一步可制备出Ag/NiFe2-xCexO4复合物,Ag/NiFe2-xCexO4复合物的组分之间存在一定的相互作用;通过银单质复合与铈离子掺杂对铁氧体的比饱和磁化强度影响较大,但对矫顽力影响不大。与单一组分相比,Ag/NiFe2-xCexO4复合物表现出更优良的微波吸收性能,当x=0.08时,s11(Ag/NiFe1.92Ce0.08O4)=-22.80 dB,s12(Ag/NiFe1.92Ce0.08O4)=-4.04 dB。通过掺杂与复合其介电损耗和磁损耗都有提高,介电损耗提高更明显,是颇具应用前景的微波吸收材料。

Preparation and characterization of Ag/NiFe2-xCexO4 as microwave absorbing composite

Ce^3+doped nickel ferrite(Ag/NiFe2-xCexO4)was composited with silver by hydrothermal method.The structure,morphology and electromagnetic properties of the product were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),vibration sample magnetometer(VSM)and vector network analyzer(VAN).The results showed that the titled composite could be prepared by hydrothermal method in one step,and there was a certain interaction between the components of Ag/NiFe2-xCexO4 composite.The specific saturation magnetization of ferrites was greatly affected by compositing with silver and the doping amount of cerium ion,but there were little effects on coercivity.Compared with single component of NiFe2O4,Ag/NiFe2-xCexO4 composite exhibited better microwave absorption performance.When x was set at 0.08,s11 and s12 for Ag/NiFe1.92Ce0.08O4 were-22.8 and-4.04 dB,respectively.Both the dielectric loss and the magnetic loss of the composite were improved,and the effects on the dielectric loss were more obvious.It shows that the composite was a promising microwave absorbing material.