Eu3+ Doped CaWO4—A Potential Red Long Afterglow Phosphor

Abstract

In this study, a series of Eu3+ doped CaWO4 phosphors were synthesized by the solid-state reaction method. Red long afterglow was observed after samples were excited with 254 nm. The main emission peaks were ascribed to the 5D0–7F J (J=0, 1, 2, 3, 4) transitions of Eu3+, and the duration of the optimal sample could last nearly 40 min in the dark seen with naked eyes. The effect of the doping concentration of Eu3+ and alkali metal charge compensators (Li, Na, K) on the luminescent properties of the products were investigated in detail. The proposed mechanism of this afterglow property is also discussed.