纳米结构CoxFe3-xO4多孔微球的磁性及交换偏置效应研究

用乙二醇为溶剂,用三氯化铁、二氯化钴和醋酸铵为起始反应试剂,通过溶剂热反应首次合成了纳米结构Co_xFe_3-xO₄多孔微球.用X射线衍射仪(XRD)、透射电子显微镜(TEM)和扫描电子显微镜(SEM)表征样品的结构和形貌,结果表明,所制备的单分散Co_xFe_3-xO₄多孔微球为立方多晶结构,其直径约300 nm,是由约30 关键词： xFe_3-xO₄')" href="#">Co_xFe_3-xO₄ 多孔微球 磁性 交换偏置效应

Magnetic properties and exchange bias effect of nano-structure CoxFe3-xO4 porous microspheres

Nano-structure Co_xFe_3-xO₄ porous microspheres are synthesized in ethylene glycol (EG) solution, using FeCl₃·6H₂O, CoCl₂·6H₂O and NH₄Ac as the starting materials through solvothermal route. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) are used to characterize the structures of synthesized products. The results show that monodisperse Co_xFe_3-xO₄porous microspheres with polycrystal structures are assembled by nanoparticles, and the average diameters is about 300 nm. The magnetic properties are evaluated with a vibrating sample magnetometer (VSM). The results indicate that the saturation magnetization ( M_s) and the Curie temperature (T_c) first increase and then decrease, and the coercivity (H_c) increase with the increase of Co²⁺ content. According to the hysteresis loops at different temperatures, Co_xFe_3-xO₄ porous microspheres possess remarkable exchange bias effects at low temperatures.