Long lasting phosphorescence properties and multi-peak fitting on thermoluminescence of red LaAlO3:Eu3+ phosphor

Abstract

Red long lasting phosphorescence(LLP) was firstly observed in LaAlO 3 :Eu 3+ phosphor synthesized by solid state method at 1773 K. It reveals that the Eu 3+ ions occupy the asymmetric La 3+ sites, resulting in the orange-red emission of Eu 3+ . The LLP of the optimum LaAlO 3 :0.6%Eu 3+ sample can come to about 2000 s according to a definition of 0.32 mcd/m 2 . The LLP decay curve can not be fitted even by a function of three exponential terms, due to the complicated retrapping process of carriers. The result of a classical multi-peak fitting method on thermoluminescence reveals that the excellent LLP performance of LaAlO 3 :Eu 3+ material originates from the rich distribution of shallow traps(E=0.7875 eV).

Thermoluminescence as a Research Tool to Investigate Luminescence Mechanisms

“…It shows that they act as suitable electron traps like co-dopants of trivalent lanthanides ions in YPO 4 :Ce 3+ ,Ln 3+ . Again, TL is shown to be a sensitive technique to determine energy levels in the band gap and is therefore widely used in the study of persistent luminescence phosphors, as illustrated by the many publications in this field [28,29,78,79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96]. …”