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SiO 2 @Y 2 O 3 :Eu hollow mesoporous microspheres were prepared by coating luminescent Y 2 O 3 :Eu 3? particles onto uniform silica spheres using melamine formaldehyde microspheres as sacrificial templates. Various approaches including X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, thermogravimetric and differential thermal analysis, photoluminescence spectroscopy and N 2 adsorption/desorption were used to characterize the samples. The results indicate that Y 2 O 3 :Eu 3? particles have been coated onto the hollow silica spheres with 300 nm thickness shell, and the composite microspheres exhibit mesoporous characteristics and have spherical morphology. Upon ultraviolet excitation, the composite shows the characteristic 5 D 0 -7 F 1-4 red emission lines of Eu 3? even after loading of the model drug. In addition, drug release tests suggest that the composite has a controlled drug release property with ibuprofen as the model drug.

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Subglobose YBO 3 :Ln 3? (Eu, Tb) phosphors have been successfully synthesized via a simple solutionbased hydrothermal method using Y 2 (CO 3 ) 3 (H 2 O) 2 colloid spheres as the precursor. The crystal structure, morphology, chemical composition and photoluminescence property of the phosphors were investigated by X-ray diffraction (XRD), transmission electron microscope, Fourier transform infrared (FTIR) spectroscopy and fluorescence spectrophotometer. The as-prepared phosphors present subglobose morphology and have a diameter of about 1 lm. XRD and FTIR results confirm that the vaterite-type YBO 3 can be synthesized by this method. The YBO 3 :Eu 3? exhibited strong orange emission at 591 nm and red emission at 610 nm, which were respectively ascribed to the ( 5 D 0 -7 F 1 ) and ( 5 D 0 -7 F 2 ) transitions of Eu 3? . The YBO 3 :Tb 3? showed dominant green emission at 542 nm due to the 5 D 4 -7 F 5 transition of Tb 3? .

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