Synthesis and characterization of monodispersed SiO2@Y3Al5O12:Er3+ core-shell particles.

Submicron core-shell structure particles SiO2@Y3Al5O12:Er3+, which silica spherical particles was coated with an yttrium aluminum garnet (Y3Al5O12) layer doped with Er3+, were prepared by the modified Pechini-Type sol-gel method for the first time. The structure and morphology of samples were detected by the X-ray powder diffraction (XRD) measurement, field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), respectively. The results indicate that well-crystallized garnet nanocrystallines were formed on the surface of the silica particles. The luminescent spectra in near infrared and visible region of the core-shell structured SiO2@Y3Al5O12:Er3+ powders were also investigated and compared with those of the pure Y3Al5O12:Er3+ and the Er3+ doped silicate glass. The results show that mono-dispersed SiO2@Y3Al5O12:Er3+ core-shell spherical particles with the near infrared, red and green luminescent emissions under the excitation of 980 nm laser diode have been successfully synthesized.