Luminescence properties of a new green afterglow phosphor NaBaScSi2O7:Eu2+

Abstract

A novel green afterglow phosphor NaBaScSi₂O₇:Eu²⁺ was prepared by a solid state reaction under a reductive atmosphere. The NaBaScSi₂O₇:Eu²⁺ phosphor shows two emission bands centered at about 424 (weak) and 502 nm (strong) due to the substitution of Eu²⁺ in both Ba⁺ and Na²⁺ sites, and energy transfer from Eu_Ba (424 nm) to Eu_Na (502 nm) was found. Both Eu_Ba and Eu_Na contribute to the afterglow process while Eu_Na dominates. Na_0.99BaScSi₂O₇:0.01Eu²⁺ exhibits green long lasting phosphorescence, whose duration is more than 1 h. The thermoluminescence properties of NaBaScSi₂O₇:Eu²⁺ and the relationship between thermoluminescence and thermal quenching properties were discussed in detail. This work provides a new and efficient candidate for long lasting phosphorescence materials.