Photoluminescence of Eu2+ in BaF2-rich fluorohalides and photostimulation after X-ray irradiation

B. Es-Sakhi (1) , Alain Garcia (2) , L. Struye (3) , P. Willems (3) , P. Leblans (3) , A. Moudden (1) , Claude Fouassier (2)

1 Université Ibn Zhor
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
3 Agfa-Gevaert

The luminescence of Eu2+ has been investigated in two families of BaF2-rich fluorohalides, Ba12Cl5(1−x)Br5xF19 (x≤0.8) and Ba7Cl2(1−x)Br2xF12 (x≤0.5). In the two kinds of host lattices, under UV excitation Eu2+ shows an intense blue 5d→4f band emission at 300 K. At low temperature, in addition to the latter, 4f→4f lines are present in the near UV. The efficiency of the photostimulated luminescence (PSL) after X-ray irradiation has been measured and compared with that of BaXF:Eu (X=Cl, Br). High conversion efficiencies have been obtained with compositions Ba12Cl5(1−x)Br5xF19 for stimulation at 532 nm. The presence of bromine is beneficial. For all compositions a high stimulation energy (SE) is needed to excite Eu2+ ions through colour centres.

Mots clés: Photoluminescence; Photostimulation; Storage phosphors; Eu2+-doped barium chlorofluoride

Domaines: Matériaux

B. Es-Sakhi, Alain Garcia, L. Struye, P. Willems, P. Leblans, et al.. Photoluminescence of Eu2+ in BaF2-rich fluorohalides and photostimulation after X-ray irradiation. Materials Science and Engineering: B, 2003, 96 (3), pp.233-239. ⟨10.1016/S0921-5107(02)00327-6⟩. ⟨hal-00198554⟩