Synthesis of Eu2O3 hollow submicrometer spheres through a sol–gel template approach

Submicrometer-sized hollow Eu2O3 spheres with a shell thickness of about 75 nm and inner diameter about 690 nm have been synthesized through a sol–gel method using PS/PE microspheres as templates. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Field emission scanning electron microscopy (FESEM), and photoluminescence (PL) spectroscopy have been used for the characterization of the obtained hollow Eu2O3 spheres. The PL peak is obviously broadened compared with that of bulk Eu2O3. The mechanism of the formation of the hollow Eu2O3 spheres was discussed.