Abstract Nanoparticles of nickel zinc ferrite Ni0.65Zn0.35Fe2O4 having an average crystallite size of 42 nm, synthesized by sol–gel method were found to exhibit the highest value of saturation magnetization along with high dc resistivity. The observed variations in saturation magnetization and crystallite size as a function of annealing temperature were elucidated considering the core surface magnetic interactions and the particle shape of the nanoferrite using low temperature in-field Mossbauer measurements and the high-resolution transmission electron micrographs. With the attainment of valuable magnetization and resistivity, the usefulness of the material as magnetic core for high frequency applications has been investigated by studying the frequency dependence of initial permeability. Interestingly, the results support that the material would be suitable as magnetic core up to 18 GHz.

中文翻译：

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Ni-Zn 纳米铁氧体表面自旋倾斜的研究及其作为微波应用磁芯的开发

摘要 通过溶胶-凝胶法合成的镍锌铁氧体纳米颗粒 Ni0.65Zn0.35Fe2O4 的平均晶粒尺寸为 42 nm，被发现具有最高的饱和磁化强度和高直流电阻率。考虑到核心表面磁相互作用和纳米铁氧体的颗粒形状，使用低温场内穆斯堡尔测量和高分辨率透射电子显微照片阐明了观察到的饱和磁化强度和微晶尺寸随退火温度的变化。随着获得有价值的磁化强度和电阻率，通过研究初始磁导率的频率依赖性，研究了该材料作为磁芯在高频应用中的有用性。有趣的是，