Ni1-xCoxFe2O4铁氧体纳米粉末的磁性能和微波吸收特性

Magnetic and Microwave Absorption Properties of Ni_(1-x)Co_xFe_2O_4 Ferrite Nanoparticles

利用柠檬酸溶胶-凝胶自蔓延燃烧法合成了Ni1-xCoxFe2O4(x=0,0.1,0.3,0.5)铁氧体纳米粉末。利用XRD、VSM和矢量网络分析仪测定了粉末样品的晶体结构、磁性能和电磁参数。定性分析了样品的饱和磁化强度、矫顽力、复磁导率和复介电常数随频率和Co含量的变化关系。结果表明,自蔓延的所有粉末样品经过600℃,2h高温退火后均为尖晶石相纳米晶颗粒。随着Co替代量x的增加,样品的自然共振频率先增大后减小,并对微波吸收特性有一定的改善。

The nanosized Ni1-xCoxFe2O4（x=0, 0.1, 0.3, 0.5） ferrite particles were prepared by sol-gel combusion technique. The characterization studies such as XRD, VSM and Vector Network Analyzer have been carried out to explore the crystal structure, magnetic properties and electromagnetic parameters of the samples. The relation of the saturation magnetization, coercivity, complex permeability and complex permittivity to the cobalt content and the frequency of microwave were analysed qualitatively. The resultes indicate that all the samples annealed for 2 hours at 600℃ exhibit spinel ferrite structure. The substitution of Co for Ni can shift the spontaneous resonance frequency and improve the microwave absorption property.