镍锌纳米晶铁氧体的络合溶胶-凝胶法合成及表征

Complexing Sol-Gel Method Synthesis and Characterization of Nanocrystalline Ni_(0.5)Zn_(0.5)Fe_2O_4 Ferrite

利用乙酰丙酮(AcAcH)络合溶胶-凝胶法合成了Ni0.5Zn0.5Fe2O4(NZFO)尖晶石型软磁铁氧体。采用傅里叶变换红外光谱(FTIR)技术研究了Fe、Zn、Ni 3种溶胶中AcAcH与Fe3+、Zn2+、Ni2+的结合形式,通过比较Fe、Zn、Ni溶胶与未添加AcAcH的Fe、Zn、Ni甲醇溶液的红外光谱发现,分别在1 532 cm-1、1 520 cm-1和1 520 cm-1处多了一个吸收峰,说明AcAcH都能与3种离子发生螯合反应。采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、物性测量系统(PPMS)分别表征NZFO铁氧体的相组成、微结构以及磁性能。XRD测试结果表明,NZFO铁氧体为单一尖晶石相结构;HRTEM透射结果表明,NZFO为片状,大小均匀,尺寸45 nm左右;PPMS研究结果表明,NZFO铁氧体的饱和磁化强度(Ms)和矫顽力(Hc)分别为36 emu.g-1和167 Oe。

Using Ni（CH3COO）2, ZnCl2 and Fe（NO3）3 as raw materials, methyl alcohol as solvent, cetylacetone（AcAcH） as complexing agent, nano-sized soft magnetic ferrite Ni0.5Zn0.5Fe2O4 （NZFO） powders were obtained by sol-gel method. The coordination mode between AcAcH with Fe3＋, Zn2＋, Ni2＋ ions of three sols was respectively investigated by Fourier transform infrared spectroscopy （FTIR）. Compared with the IR spectra of AcAcH-free solutions, an additional peak was observed in the AcAcH-contained IR spectra, which was respectively at 1 532 cm^-1, 1 520 cm^-1 and 1 520 cm^-1 for Fe, Zn and Ni sols. This additional peak indicated that there was a chemical coordination reaction to form chelatering structure between AcAcH with Fe^3＋, Zn^2＋, Ni^2＋ ions, respectively. The morphology, microstructure and magnetic property of NZFO were characterized by using X-ray diffraction （XRD）, transmission electron microscopy （HRTEM） and physical property measurement system （PPMS）, respectively. The characterization of XRD indicated that NZFO powders were nano-sized and spinel. The TEM image showed that NZFO were flake-shaped, about 45 nm in diameter. PPMS was used to test the magnetic property of sample, and the result showed that NZFO had a characteristic of ferro-magnetism. The saturated magnetization （Ms） and the coercive force （Hc） of NZFO nano powders were 36 emu·g-1 and 167 Oe, respectively.