The influence of temperature on the afterglow feature of SrAl₂O₄: Eu, Dy phosphors

Abstract

Using a self-designed temperature testing box in which Xenon-lamp irradiation can be applied, the afterglow feature of SrAl₂O₄: Eu, Dy as a function of temperature has been researched. Two sorts of SrAl₂O₄: Eu, Dy phosphors, namely highest quality commercial one and the self-synthesized one by solid-state reaction process were employed. Results reveal a common phenomenon behaving as phosphorescent sudden extinguishments at a certain low temperature although their threshold temperature value (about223 K) has a slight difference. The general characteristic for the influence of temperature on the afterglow feature presents, compared to the luminescent decay at room temperature (RT), a bigger and faster decrease of phosphorescent brightness with the reduction of temperature, while decay curves still maitain the same pattern composed of a quick decline part and a platform falling part during which the phosphorescent brightness at273 K is only about1/2 as big as that at RT, and at253 K the figure has changed to about1/3. Finally, the reason of previous observed results has been analyzed briefly in theory.

Keywords

afterglow / SrAl₂O₄: Eu, Dy / low temperature

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