NiFe₂O₄多层空心磁性粒子的制备与电磁性能

Preparation and Electromagnetic Properties of NiFe₂O₄ Multilayer Hollow Magnetic Particles

本文采用葡萄糖辅助的水热法和不同温度下的热处理制备了NiFe2O4多层空心磁性粒子,并通过透射电镜(TEM)表征其形貌和组成。通过热重分析(TG-DTG)、X射线衍射(XRD)、傅里叶红外光谱(FTIR)、X射线光电子能谱(XPS)研究证实了生成纯相NiFe2O4多层空心粒子。利用振动磁强计研究了NiFe2O4空心粒子的磁性能,随着煅烧温度的升高,饱和磁化强度增大,矫顽力先增大后减小。采用矢量网络分析仪调查研究了NiFe2O4多层空心磁性粒子在2~18 GHz频段的电磁特性,结果显示由于空心多层结构,粒子具有优异的微波吸收性能。结果表明,在5~10 GHz范围内,样品的微波反射损耗低于−10 dB,在7.3 GHz处达到最小值−19 dB。

In this paper, NiFe2O4 multilayer hollow magnetic particles were prepared by Glucose-assisted hydrothermal method and heat treatment at different temperatures, and their morphology and composition were characterized by transmission electron microscopy (TEM). The formation of pure NiFe2O4 hollow particles was confirmed by thermogravimetric analysis (TG-DTG), X-ray diffraction (XRD), Fourier infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The magnetic properties of NiFe2O4 hollow particles are studied by a vibrating magnetometer. With the increase of calcination temperature, the saturation magnetization increases and the coercivity increases first and then decreases. The electromagnetic characteristics of NiFe2O4 multilayer hollow magnetic particles in the 2~18 GHz band were investigated by using a vector network analyzer. The results show that the NiFe2O4 multilayer magnetic particles have excellent microwave absorption properties due to the hollow multilayer structure. The results show that the microwave reflection loss of the sample is lower than −10 dB in the range of 5~10 GHz, and reaches the minimum value of −19 dB at 7.3 GHz.