Sr₂ZnWO₆:Eu³⁺, Bi³⁺, Li⁺: a potential white-emitting phosphor for near-ultraviolet white light-emitting diodes

Abstract

A series of Sr2ZnWO6 phosphors co-doped with Eu(3+), Bi(3+) and Li(+) were prepared using the Pechini method. The samples were tested using X-ray diffraction and luminescence spectroscopy. The results show that the samples can be effectively excited by near-ultraviolet (UV) and UV light. The introduction of Bi(3+) and Li(+) significantly enhances the fluorescence emission of Sr2ZnWO6 :Eu(3+) and changes the light emitted by the phosphors from bluish-green to white. When excited at 371 nm, Sr(2-x-z)Zn(1-y)WO6:xEu(3+), yBi(3+), zLi(+) (x = 0.05, y = 0.05, z = 0.05, 0.1 and 0.15) samples emit high-performance white light. Intense red-orange emission is also observed when excited by UV light. The obtained phosphor is a potential white-emitting phosphor that could meet the needs of excitation sources with near-UV chips. In addition, this phosphor might have promising application as a red-orange emitting phosphor for white light-emitting diodes based on UV light-emitting diodes.

Keywords: Pechini method; photoluminescence; tungstate; white light.