Ultrasonic-assisted synthesis of core-shell structure Zn0.5Cr0.5Fe2O4/TiO2 nanocomposites in w/o microemulsion

The core-shell structure nanocomposites containing TiO2-coated Zn0.5Cr0.5Fe2O4 were prepared by hydrolysis of titanium tetrabutyloxide in w/o microemulsions assisted by ultrasonic irradiation. The as-prepared samples were characterized by X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and transmission electron microscopy (TEM). Structure analysis indicated that Zn0.5Cr0.5Fe2O4/TiO2 nanocomposites presented the core-shell structure, where the size of Zn0.5Cr0.5Fe2O4 core was in the range of 20-30 nm, and the thickness of TiO2 shell was 10-20 nm. The magnetic properties were investigated by using a vibrating sample magnetometer (VSM). The results of the magnetic measurement indicated the reduction of the magnetization for Zn0.5Cr0.5Fe2O4/TiO2 nanocomposites compared with the uncoated Zn0.5Cr0.5Fe2O4 particles. The formation mechanism of Zn0.5Cr0.5Fe2O4/TiO2 nanocomposites was proposed as well.