Luminescence properties of sol–gel derived spherical SiO 2@Gd 2(WO 4) 3:Eu 3+ particles with core–shell structure

Abstract

Monodisperse, core–shell structured SiO 2@Gd 2(WO 4) 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 SiO 2@Gd 2(WO 4) 3:Eu 3+ particles show strong red emission dominated by the 5D 0– 7F 2 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 Gd 2(WO 4) 3:Eu 3+ phosphor layers on SiO 2 particles, the size of the SiO 2 core particles, and by accelerating voltage and the filament current, respectively.