Photoluminescence properties of phosphors based on Lu3+-stabilized Gd3Al5O12:Tb3+/Ce3+ garnet solid solutions

Abstract The Gd 3 Al 5 O 12 :Tb/Ce (GdAG:Tb/Ce) garnet solutions effectively stabilized by Lu 3+ have been achieved by calcining their precursor at 1300 °C. Detailed characterizations are given to the materials in terms of XRD, FE-SEM, BET, PL/PLE, and fluorescence decay analysis. The occurrence of Gd 3+ and Tb 3+ transitions from the photoluminescence excitation spectrum monitoring the Ce 3+ yellow emission strongly confirmed the efficient Gd 3+  → Ce 3+ and Tb 3+  → Ce 3+ energy transfer. The [(Gd 0.8 Lu 0.2 ) 0.99− x Ce 0.01 Tb x ]AG ( x  = 0–0.1) phosphors with good dispersion and uniform particle size exhibit various luminescent properties under different excitation wavelength of 275, 338, and 457 nm, respectively. The photoluminescence comparison indicated that owing to the Gd 3+  → Ce 3+ and Tb 3+  → Ce 3+ energy transfer, the best luminescent phosphor [(Gd 0.8 Lu 0.2 ) 0.89 Ce 0.01 Tb 0.1 ]AG is almost identical to the well-known YAG:Ce, higher than LuAG:Ce in emission intensity, and has a substantially red-shifted emission band that is desired for warm-white lighting. The Tb 3+  → Ce 3+ energy transfer was suggested to be electric multipolar interactions, and the processes of energy migration among the optically active Gd 3+ , Tb 3+ , and Ce 3+ ions were discussed in detail. Fluorescence decay analysis found the lifetime for the Ce 3+ emission hardly changes with the Tb 3+ incorporation. The [(Gd 0.8 Lu 0.2 ) 0.99− x Ce 0.01 Tb x ]AG garnets developed in this work may serve as a new type of phosphor that hopefully meets the requirements of various lighting, optical display, and scintillation applications.