A simple approach for the synthesis of bi-functional Fe3O4@WO3 − x core-shell nanoparticles with magnetic-microwave to heat responsive properties

A facile direct precipitation method has been developed for the synthesis of multi-functional magnetic, microwave to heat responsive properties with Fe3O4 nanoparticles as the core and WO3 − x as the shell. Transmission electron microscopy (TEM) images revealed that the obtained bi-functional nanoparticles had a core-shell structure and a spherical morphology. The average size was ~ 250 nm, and the thickness of the shell was ~ 15 nm. The X-ray diffraction (XRD) patterns showed that a cubic spinel structure of Fe3O4 core and the WO3 − x shell were obtained. The nanoparticles showed both strong magnetic, and unique microwave to heat responsive properties, which may lead to development of nanoparticles with great potential for applications in drug targeting delivery, controlled release drug, photo- and microwave-thermal combination therapy and water treatment.