Sol-gel synthesis and photoluminescence properties of BaSO4/Y2O3:Eu3+ core-shell submicrospheres

Europium-doped nanocrystalline Y 2 O 3 phosphor layers were coated on the surface of preformed submicron BaSO 4 spheres via the sol-gel process. The obtained BaSO 4 /Y 2 O 3 :Eu 3+ core-shell phosphors were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS) and photoluminescence spectra. The results showed that the obtained BaSO 4 /Y 2 O 3 :Eu 3+ core-shell phosphors consisted of well-dispersed submicron spherical particles with narrow size distribution and non-agglomeration. TEM and EDS results showed that BaSO 4 particles were well coated with the shell of Y 2 O 3 :Eu 3+ . XRD result demonstrated that no reaction occurred between the BaSO 4 cores and the Y 2 O 3 :Eu 3+ shells even after annealing at 1200 °C. The BaSO 4 /Y 2 O 3 :Eu 3+ core-shell particles showed a red emission corresponding to 5 D 0 – 7 F 2 of Eu 3+ under the excitation of ultraviolet.