Luminescence properties of sol–gel derived spherical SiO2@Gd2(WO4)3:Eu 3+ particles with core–shell structure

Monodisperse, core–shell structured SiO2@Gd2(WO4)3:Eu 3+ particles were prepared by the sol–gel method. The samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, transmission electron microscopy, photoluminescence (PL) and low-voltage cathodoluminescence (CL). PL and CL study revealed that the core–shell structured SiO2@Gd2(WO4)3:Eu 3+ particles show strong red emission dominated by the D0– F2 transition of Eu 3+ at 615 nm with a lifetime of 0.89 ms. The PL and CL emission intensity can be tuned by the coating number of Gd2(WO4)3:Eu 3+ phosphor layers on SiO2 particles, the size of the SiO2 core particles, and by accelerating voltage and the filament current, respectively. 2006 Elsevier B.V. All rights reserved.