Preparation and characteristics of Ni _xFe _3-xO ₄-encapsulated hollow glass spheres by ferrite plating

Hollow glass spheres were encapsulated with a layer of Ni _xFe _3-xO ₄ film in the open air by ferrite plating; the films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersion spectroscopy (EDS). The films encapsulated on the surface of hollow glass spheres with thickness at about 0.5μm had amorphous structure. The proportion of nickel to iron in the films was affected by the proportion of reactants and the synthetic conditions. Hysteresis loops determined by vibrating sample magnetometer (VSM) indicated that the films had ferromagnetic behavior after anneal.