多铁材料Ni_3V_2O_8的熔盐法制备与磁学性能

Molten salt synthesis and magnetic properties of multiferroic materials Ni_3V_2O_8

分别采用熔盐法和固相反应法制备了Ni3V2O8多铁材料样品,并利用X射线衍射(XRD)、扫描电子显微镜(SEM)、能谱(EDS)、透射电子显微镜(TEM)、高分辨透射电镜(HRTEM)等表征手段分析了所得样品的物相、微观形貌及结构,并研究了其磁学性能。实验结果表明,采用熔盐法和固相反应法制备的Ni3V2O8样品均为单一物相,呈正交对称型的晶体结构;熔盐法制备所得的样品呈棒状,颗粒直径约为20μm,长度约为100μm,单个晶粒呈明显的单晶特征;而固相反应法制备的Ni3V2O8样品呈颗粒状,颗粒尺寸约为25μm,分布较均匀。熔盐法制备的Ni3V2O8具有反铁磁性相变,相变温度在3.6 K左右,有效磁矩为3.34μB。

TheNi3V2O8 multiferroic material samples were prepared by the molten salt synthesis and solid state reaction method, respectively. The phase composition, microstructure and crystal structure of the obtained samples as well as the magnetic properties were analyzed by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, energy dispersive spectrometer （EDS）, transmission electron microscopy （TEM） and the high resolution transmission electron microscopy （HRTEM）. The results show that the obtained samples for both preparing methods are of single phase with orthorhombic symmetry. The microstructure analysis of the samples prepared by the molten salt synthesis reveal the well crystallized Ni3V2O8 polycrystalline samples. The Ni3V2O8 sample prepared by the molten salt synthesis method shows stick-like shape with about 20μm in diameter and about 100μm in length; the Ni3V2O8 sample prepared by the solid state reaction method shows well dispersed grain shape with an average particle size of about 25μm.The Ni3V2O8 sample prepared by the molten salt method has antiferromagnetic phase transition with temperature of 3.6 K and effective magnetic moment of 3.34μB.