采用静电纺丝技术制备了添加0～20wt％ Al2O3的Ni0.5Zn0.5Fe2O4纳米纤维.通过XRD、FESEM、TEM和VSM对样品的物相结构、形貌和磁性能进行了表征.结果表明,所合成的复合纳米纤维的直径都分布在40～150 nm之间,添加到纤维中的Al2O3主要以非晶态形式分布于铁氧体晶粒边界;随着Al2O3添加量的增加,可观察到y-Fe2O3相逐渐析出,Ni-Zn铁氧体的晶格常数单调减小,说明有一些Al2O3进入到尖晶石晶格中取代了B位的Fe3+离子,Ni-Zn铁氧体的平均晶粒尺寸先增大后减小,在Al2O3添加量为8wt％时达到最大值39.2 nm;比饱和磁化强度和矫顽力随Al2O3添加量的增加呈现出相同的变化规律,先减小后增大,当Al2O3添加量超过5wt％时又开始变小.%Ni0.5Zn0.5Fe2O4 nanofibers with the addition of different weight percents of A12O3 in the range 0 to 20wt% were fabricated by electrospinning technique. The phase structure, morphology and magnetic properties of the samples were characterized by XRD, field emission scan electron microscopy (FESEM), TEM and vibrating sample magnetometer (VSM). The results show that the diameters of the synthesized composite nanofibers range from 40 to 150 nm. The AI2O3 added into the nanofibers mainly tend to distribute on the grain boundary in the amorphous form. With increasing the amount of AI2O3 addition from 0 to 20wt%, the lattice parameter of Ni-Zn ferrite phase monotonously decreases and the y-Fe2O3 phase gradually precipitates, which indicate that the small amount of AI2O3 may enter into the spinel lattice and replace Fe3+ ions at B-sites. Furthermore, the average grain size of Ni-Zn ferrite initially increases with AI2O3 addition, reaches to a maximum at 8wt%, and then decreases with a further increase in A12O3 content. Room temperature magnetic measurements reveal that the specific saturation magnetization and coercive force of the nanofibers exhibit the same dependence on A12O3 addition. Their values firstly decrease and then increase with increasing A12O3 content in the range of less than 5wt%, and subsequently decrease again when the content of AI2O3 is over 5wt%.
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