Photoluminescence and Afterglow Behavior of Eu2+, Dy3+ and Eu2+, Sm3+ in Sr3Al2O6 Matrix

Abstract

The long afterglow luminescent materials Sr3Al2O6: Eu, Sm and Sr3Al2O6: Eu, Dy (denoted as S1 and S2, respectively) were synthesized via solid-state reaction. X-ray diffraction, fluorescence spectrophotometer and thermal luminescent spectroscope were employed to characterize the phosphors. The excitation spectra are all well simulated by eight Gaussian curves, indicating that they originate from the 4f7(8S7/2)–4f65d(8HJ) transitions of Eu2+. The excitation spectra intensity of S1 is much stronger than that of S2, which indicates that there is a more efficient energy transfers from Sm3+ to Eu2+. The thermally stimulated luminescence (TSL) curve can be fitted to four TSL peaks and the low-temperature TSL peak is responsible for the long lasting phosphorescence. The proposed explanation for the afterglow property is discussed.