Preparation of SrSi2 O2 N2: Eu2+ Phosphor by SrSi Alloy Precursor and Its Long-lasting Phosphorescence Properties.

Oxynitride long-lasting phosphorescence ( LLP) phosphor SrSi₂ O₂ N₂: Eu²⁺ was prepared by a new method using SrSi alloy as a precursor. Its properties were systematically investigated utilizing XRD, photoluminescence, excited-state decay curve, long-lasting phosphorescence, and thermoluminescence spectrum. This phosphor was found to be well-crystallized by calcinations of the Sr_{1− x} Eu _x Si alloy and the SiO₂ mixture at 1400°C for 3 h. After irradiation under the 280 nm UV light, the afterglow emission of Eu²⁺ (4 f⁶5 d¹ → 4 f⁷) was obviously observed for at least 2 h in the limit of light perception of dark-adapted human eyes (0.32 mcd/m²). Furthermore, the possible mechanism for the LLP of SrSi₂ O₂ N₂: Eu²⁺ phosphor is also discussed in this article. [ABSTRACT FROM AUTHOR]