Synthesis of Hollow SiO_2 Nanoparticles from Dy_2O_3@SiO_2 Core-Shell Nanocomposites via a Recyclable Sonochemical Method

摘要

Hollow silica nanoparticles were prepared from Dy_2O_3@SiO_2 core-shell nanocomposites, for the first time, by a simple ultrasonic assisted sol-gel method. The Dy_2O_3@SiO_2 core-shell nanocomposites were prepared by the deposition of a SiO_2 layer onto the surface of Dy_2O_3 nanoparticles using a three-step coating process. The hollow SiO_2 nanostructures were obtained by selective removal of the Dy_2O_3 cores. The structure, morphology and composition of the products were determined by the techniques of X-ray diffraction, Fourier transfom infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that hollow SiO_2 nanostructures were sphere-like shape with the average size of 20 nm and had an amorphous crystal structure. The important advantage of this process is the recyclability of the Dy_2O_3 nanoparticles as the starting material of the reaction.