Photoluminescence Properties of Li6Gd(BO3)3:Tb3+ Under VUV / UV Excitation

A series of phosphors Li6Gd1-x(BO3)3:xTb3+ (0:x:1) was prepared by a conventional solid-state reaction method and their photoluminescence properties under VUV/UV excitation were demonstrated. For the excitation spectrum, the host-related absorption band, f-f and f-d transitions of Gd3+ and Tb3+, charge transfer of O2--Gd3+ and O2--Tb3+ were assigned. In Li6Gd(BO3)3:Tb3+, visible quantum cutting through downconversion was observed upon Tb3+ 4f8-4f75d1 excitation and host excitation. The quantum cutting process was demonstrated combining a possible model.