The Research Of Trap Center Regulation To Achieve Long Afterglow Luminescence At Different Temperatures

Persistent luminescent material is a special kind of photoluminescence material.It can store part of the light energy after radiation by ultra violet or visible light.After the stoppage of the radiation,the energy will be released under the thermal disturbance available from surrounding environment,which shows a persistent luminescence.This special phenomenon is mainly due to the cooperation of two important centers,emitter center and trap center.The transition from the excited state to the ground state level of the emitter center implements the luminescence process;the trap center can capture carriers from the emitter center and then release them back to the emitter center,which is the key to achieve persistent luminescence.The trap center is usually a point defect in the material.From the point of view of defect structure,the properties and applications of persistent luminescent materials with different defect structure designs at different temperatures are studied in this paper.?1?The defect structure and persistent luminescence properties of Ca₃Ga₂Ge₃O₁₂:Eu²⁺,Tm³⁺room temperature persistent luminescent materials have been studied.With increasing the concentration of deep traps,the carriers in deep traps can also be effectively utilized with persistent luminescence through energy transfer between deep traps and shallow traps,thus achieving room temperature persistent luminescence with stronger initial brightness and longer lifetime.?2?The defect structure and persistent luminescence properties of NaBaScSi₂O₇:Tb³⁺high temperature long afterglow luminescent materials have been studied.These studies show that the isolate defect structures with different depths have a positive impact on high temperature persistent luminescent materials.?3?The low temperature persistent luminescent materials Ba₄Si₆O₁₆:Eu²⁺,Pr³⁺have been developed in this paper.The defect structure and luminescent properties of low-temperature persistent luminescent materials are firstly studied,and their practical applications are preliminarily explored.