文摘
The metastable garnet lattice of Yb/Er co-doped Gd3Al5O12 (GdAG:Yb/Er) has been effectively stabilized by doping with significantly smaller Lu3+ to form (Gd,Lu)AG:Yb/Er solid solutions. The phase-pure (Gd,Lu)AG:Yb/Er garnet particles have been successfully achieved by calcining their respective precursors synthesized via carbonate co-precipitation. Partially replacing Gd3+ with Lu3+ up to 50 at% (x=0.5) not only lowers the temperature of garnet crystallization, but also raises the theoretical density of the material. The resultant [(Gd1−xLux)0.948Yb0.05Er0.002]AG (x=0.1–0.5) powders, with good dispersion and fairly uniform particle morphology, exhibit strong green (~510 to 590 nm, 2H11/2, 4S3/2→4I15/2 transitions of Er3+) and red (~635 to 700 nm, 4F9/2→4I15/2 transition of Er3+) emissions under 978 nm laser excitation. The Lu3+ incorporation effect on the visible emission color and intensity of Er3+, as well as the dependence of emission intensity on pumping power were all discussed in detail. The up-conversion phosphor of Yb/Er codoped (Gd,Lu)AG garnet developed in this work may potentially be used as a new type of luminescent material.