Up-conversion luminescence of new phosphors of Gd 3 Al 5 O 12 :Yb/Er stabilized with Lu 3+

Abstract The metastable garnet lattice of Yb/Er co-doped Gd 3 Al 5 O 12 (GdAG:Yb/Er) has been effectively stabilized by doping with significantly smaller Lu 3+ 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 Gd 3+ with Lu 3+ 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 [(Gd 1− x Lu x ) 0.948 Yb 0.05 Er 0.002 ]AG ( x =0.1–0.5) powders, with good dispersion and fairly uniform particle morphology, exhibit strong green (~510 to 590 nm, 2 H 11/2 , 4 S 3/2 → 4 I 15/2 transitions of Er 3+ ) and red (~635 to 700 nm, 4 F 9/2 → 4 I 15/2 transition of Er 3+ ) emissions under 978 nm laser excitation. The Lu 3+ incorporation effect on the visible emission color and intensity of Er 3+ , 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.