Synthesis and characterization of mono-dispersed Y3Al5O12:Er3+-coated SiO2 nanoparticles by co-precipitation process

Abstract

In this paper, a facile co-precipitation process for preparing mono-dispersed core-€“shell structure nanoparticles is reported. The 110 nm SiO2 cores coated with an yttrium aluminum garnet (Y3Al5O12) layer doped with Er3+ were synthesized and the influence of the concentration ratio of [urea]/[metal ions] on the final product was investigated. The structure and morphology of samples were characterized by the X-ray powder diffraction, Fourier transform IR spectroscopy and transmission electron microscopy, respectively. The results indicate that a layer of well-crystallized garnet Y3Al5O12:Er3+ were successfully coated on the silica particles with the thickness of 20 nm. The near infrared and upconversion luminescent spectra of the SiO2@Y3Al5O12:Er3+ powders further confirm that a Y3Al5O12:Er3+ coating layer has formed on the surface of silica spherical particles.