Controlled synthesis and room-temperature ferromagnetism of CaWO4 nanostructures

CaWO4 nanostructures (nanospheres, nanorods and nanoplates) were synthesized by a hydrothermal process. The morphology, size and composition of these nanostructures were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray energy dispersive spectroscopy (EDS). Based on the electron microscope observations, the growth of such nanostructures has been proposed as an Ostwald ripening process followed by self-assembly. Furthermore, magnetic measurement of these CaWO4 nanostructures indicates as-prepared CaWO4 nanostructures possess obvious room-temperature ferromagnetism, suggesting the potential of CaWO4 nanostructures in applications. (C) 2015 Elsevier B.V. All rights reserved.