Influence of Tl+ activator ions on the luminescence characteristics of KCl0.5Br0.5:Eu2+ powder phosphors

✍ Scribed by S. Nagarajan; R. Sudarkodi

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 754 KB
• Volume: 24
• Category: Article
• ISSN: 1522-7235
• DOI: 10.1002/bio.1090

✦ Synopsis

Abstract

Photoluminescence (PL) of thallium co‐doped with KCl~0.5~Br~0.5~:Eu^2+^ powder phosphors display emission bands at 320 and 370 nm attributable to centres involving Tl^+^ ions in addition to characteristic Eu^2+^ emission around 420 nm. Additional PL excitation and emission bandS observed around 260 and 380 nm, respectively, were observed in the double‐doped KCl~0.5~Br~0.5~:Eu^2+^, Tl^+^ powder phosphors and are attributed to complex centres involving Tl^+^ and Eu^2+^ ions. The enhancement observed in the intensity of Eu^2+^ emission around 420 nm with the addition of TlBr in KCl~0.5~Br~0.5~:Eu^2+^ powder phosphors is attributed to the energy transfer from Tl^+^ → Eu^2+^ ions. Photostimulated luminescence (PSL) studies of γ‐irradiated KCl~0.5~Br~0.5~:Eu^2+^, Tl^+^ mixed phosphors are reported and a tentative PSL mechanism in the phosphors has been suggested. Copyright © 2009 John Wiley & Sons, Ltd.