SiO@GdMoO:Eu core-shell phosphors were prepared by the sol-gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectra (EDS), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as kinetic decays were used to characterize the resulting SiO@GdMoO:Eu core-shell phosphors. The XRD results demonstrate that the GdMoO:Eu layers on the SiO spheres begin to crystallize after annealing at 600 °C and the crystallinity increases with raising the annealing temperature. The obtained core-shell phosphors have a near perfect spherical shape with narrow size distribution (average size ca. 600 nm), are not agglomerated, and have a smooth surface. The thickness of the GdMoO:Eu shells on the SiO cores could be easily tailored by varying the number of deposition cycles (50 nm for four deposition cycles). The Eu shows a strong PL luminescence (dominated by D-F red emission at 613 nm) under the excitation of 307 nm UV light. The PL intensity of Eu increases with increasing the annealing temperature and the number of coating cycles. © 2006 Elsevier B.V. All rights reserved.