title: Monodisperse and core-shell-structured SiO2@YBO3:Eu3+ spherical particles: synthesis and characterization.
abstract: Y0.9Eu0.1BO3 phosphor layers were deposited on monodisperse SiO2 particles of different sizes (300, 570, 900, and 1200 nm) via a sol-gel process, resulting in the formation of core-shell-structured SiO2@Y0.9Eu0.1BO3 particles. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), and cathodoluminescence (CL) spectra as well as lifetimes were employed to characterize the resulting composite particles. The results of XRD, FE-SEM, and TEM indicate that the 800 degrees C annealed sample consists of crystalline YBO3 shells and amorphous SiO2 cores, in spherical shape with a narrow size distribution. Under UV (240 nm) and VUV (172 nm) light or electron beam (1-6 kV) excitation, these particles show the characteristic 5D0-7F1-4 orange-red emission lines of Eu3+ with a quantum yield ranging from 36% (one-layer Y0.9Eu0.1BO3 on SiO2) to 54% (four-layer Y0.9Eu0.1BO3 on SiO2). The luminescence properties (emission intensity and color coordinates) of Eu3+ ions in the core-shell particles can be tuned by the coating number of Y0.9Eu0.1BO3 layers and SiO2 core particle size to some extent, pointing out the great potential for these particles applied in displaying and lightening fields.
authors.affiliation: Key laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, PR China.
authors.forename: Cuikun
authors.initials: C
authors.lastname: Lin
authors.forename: Deyan
authors.initials: D
authors.lastname: Kong
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
authors.forename: Huan
authors.initials: H
authors.lastname: Wang
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.forename: Jun
authors.initials: J
authors.lastname: Lin
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D002412:Cations / Q000737:chemistry*; D005063:Europium / Q000737:chemistry*; D008163:Luminescent Measurements; D008855:Microscopy, Electron, Scanning; D015394:Molecular Structure; D012822:Silicon Dioxide / Q000138:chemical synthesis / Q000737:chemistry*; D014961:X-Ray Diffraction; D015019:Yttrium / Q000737:chemistry*
chemical_list: D001896:Boron Compounds; D002412:Cations; C519834:YBO3 compound; D005063:Europium; D015019:Yttrium; D012822:Silicon Dioxide