Energy Transfer and Spectroscopic Characterization of New Green Emitting Li_3Ba_2Gd_3(WO_4)_8: Tb~(3+) Phosphor

摘要

A new tungstate family, Li_3Ba_2Gd_3(WO_4)_8 doped with Tb~(3+) is synthesized by using the traditional solid-state reaction to explore and further expand new pure green phosphors with higher performance in the field of solid-state source markets, white light-emitting diodes (WLEDs). The X-Ray patterns show that Gd~(3+)-Gd~(3+) ion coordination units and tungstate zigzags constitute the main structure of the host material, and they are isolated by the [WO_4]~(2-) groups. The critical concentration of Tb~(3+) is up to x=2.0 among the series Tb~(3+) doped Li_3Ba_2Gd_3(WO_4)_8 phosphors, which should result from the interaction between Gd~(3+) ions, of course, including the electronic transition from WO_4~(2-) ions. The characteristic green emission peaks (~5D_4→~7F_5) at around 547 nm are also observed, and the optimal doping concentration is x=2.0 which possess the highest luminescent intensity.