High-efficient fabrication of core-shell-shell structured SiO@GdPO:Tb@SiO nanoparticles with improved luminescence.

SiO@GdPO:Tb@SiO nanoparticles with core-shell-shell structure were successfully synthesized by a cheap silane coupling agent grafting method at room temperature. This method not only homogeneously coated rare-earth phosphate nanoparticles on the surface of silica spheres but also saved the use of rare-earth resources. The obtained nanoparticles consisted of SiO core with a diameter of approximately 210 nm, GdPO:Tb intermediate shell with thickness of approximately 7 nm, and SiO outer shell with thickness of approximately 20 nm.

Controlled synthesis and luminescence properties of core-shell-shell structured SiO@AIPA-S-Si-Eu@SiO and SiO@AIPA-S-Si-Eu-phen@SiO nanocomposites.

Two novel core-shell structured SiO@AIPA-S-Si-Eu and SiO@AIPA-S-Si-Eu-phen nanocomposites have been synthesized by a bifunctional organic ligands ((HOOC)CHNHCONH(CH)Si(OCHCH)) (defined as AIPA-S-Si) connected with Eu ions and silica via covalent bond. And the corresponding core-shell-shell structured SiO@AIPA-S-Si-Eu@SiO and SiO@AIPA-S-Si-Eu-phen@SiO nanocomposites with enhanced luminescence have been synthesized by tetraethyl orthosilicate (TEOS) hydrolysis co-deposition method. The composition and micromorphology of the nanocomposites were characterized by means of Fourier-transform infrared spectroscopy (FT-IR), thermal gravimetric analysis (TG), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectrometry (EDX) and X-ray photoelectron spectroscopy (XPS).

Luminescence Studies and Judd-Ofelt Analysis on SiO@LaPO:Eu@SiO Submicro-spheres with Different Size of Intermediate Shells.

The novel submicro-spheres SiO@LaPO:Eu@SiO with core-shell-shell structures were prepared by connecting the SiO submicro-spheres and the rare earth ions through an organosilane HOOCCHN(CONH(CH)Si(OCHCH) (MABA-Si). The as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and infrared spectroscopy (IR). It is found that the intermediate shell of the submicro-spheres was composed by LaPO:Eu nanoparticles with the size of about 4, 5-7, or 15-34 nm.