Nanoparticles-assembled CaWO4:Tb3+ hollow microspheres: Glycine-assisted fabrication, characterization and photoluminescence

Uniform CaWO4:Tb3+ hollow microspheres with 3-4 μm diameter assembled by nanoparticles have been successfully fabricated via a simple hydrothermal route by using glycine as the structure directing agent. The glycine-assisted hydrothermal method is facile and effective in preparing CaWO4 hollow structures. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to characterize the crystalline phase and morphologies of the products. The effects of synthesis parameters on the morphologies of the as-prepared structures were investigated by SEM. It is found that the amount of glycine and reaction time all play crucial roles in the formation of CaWO4 hollow microspheres. The N2 adsorption-desorption and photoluminescent (PL) properties of the CaWO4:Tb3+ hollow microspheres were measured.