均匀共沉淀法制备BaTiO_3-Ni_xZn_(1-x)Fe_2O_4核-壳粒子及其性能

Preparation and Characterization of BaTiO_3-Ni_xZn_(1-x)Fe_2O_4 Core-shell Particles by Homogeneous Coprecipitation

以尿素为沉淀剂,在无后续热处理的情况下,采用均匀共沉淀法制备了BaTiO3-NixZn1-xFe2O4核-壳粒子.采用透射电子显微镜(TEM)、X射线衍射仪(XRD)、能谱仪(EDS)及振动样品磁强计(VSM)对BaTiO3-NixZn1-xFe2O4核-壳粒子的形貌、结构、成分和磁性能进行了表征.结果表明,制备的核-壳结构粒子中NixZn1-xFe2O4壳层在BaTiO3颗粒的表面包覆完整.通过控制共沉淀中NiCl2.6H2O与ZnCl2的摩尔比可以调控BaTiO3-NixZn1-xFe2O4核-壳粒子的磁性;加入的NiCl2.6H2O与ZnCl2摩尔比为7∶3时制得的核-壳粒子具有较好的磁性能,其饱和磁化强度和矫顽力分别为26.999 A.m2/kg和902.787 A/m.

BaTiO3-NixZn1-xFe2O4 core-shell particles were prepared by plating NixZn1-xFe2O4 magnetic films on BaTiO3 via homogeneous coprecipitation with urea as the precipitator.The phase structure,morphology,particle size,shell thickness,chemical composition and magnetic performance of the core-shell particles were characterized by X-ray diffraction（XRD）,transmission electron microscopy（TEM）,energy dispersive X-ray spectroscopy（EDS） and vibrating sample magnetometer（VSM）,respectively.The results show that compact and continuous coatings of NixZn1-xFe2O4 are formed on the surface of the BaTiO3.The magnetic performance of BaTiO3-NixZn1-xFe2O4 core-shell particles could be controlled via regulating the molar ratio of NiCl2·6H2O to ZnCl2 added in the experiment.When the molar ratio of NiCl2·6H2O to ZnCl2 is 7∶ 3,the saturation magnetization（Ms） and the coercivity（Hc） of the as-sample are 26.999 A·m2/kg and 902.787 A/m,respectively.