Investigation on Synthesis and Property of Tb³⁺/Dy³⁺ Co-Doped Gd₃Al₅O₁₂ Phosphor

Abstract

The (Gd0.9-xTb0.1Dyx)3Al5O12 (x=0-0.04, GdAG:Tb3+/Dy3+) solid solution was acquired by calcining their respective precursor prepared via co-precipitation method at 1500 °C. The performance of GdAG:Tb3+/Dy3+ powders was characterized by combined technology of Fourier transform infrared absorption spectra (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) and photoluminescence (PL) spectrum analyses. The metastable Gd3Al5O12 could be stabilized by doping smaller Tb3+ ions of 10 at.%. Under the optimal UV excitation of 275 nm, the GdAG:Tb3+/Dy3+ phosphors exhibit vivid green emission at 548 nm which were attributed to the 5D4→7F5 transition of Tb3+. The CIE chromaticity coordinate was determined at (~0.32, ~0.48) with the color temperature of ~5872 K. Compared to the Dy3+-free (Gd0.9Tb0.1)AG phosphor, the emission intensity of Dy3+-doped phosphors display stronger owing to the efficient energy transfer from Dy3+ to Tb3+. The optimal amount of Dy3+ in GdAG:Tb3+/Dy3+ phosphors was determined to be ~2.5 at.% (x=0.025). The GdAG:Tb3+/Dy3+ phosphors developed in present work are expected to be a new type of green phosphor widely used in the lighting and display areas.

Synthesis and Property Investigation on the Spherical Lu₃Al₅O₁₂:Tb³⁺ Phosphor with Green Emitting

“…Figure 4 shows the photoluminescence (PL) spectra of (Lu 1-x Tb x )AG with the Tb 3+ addition. Under 276 nm-excitation, all the PL spectra mainly consists four emission bands peaked at 492, 545 (the strongest), 591, and 625 nm which are assigned to 5 D 4 → 7 F J (J=3-6) as labeled in the Figure 4a [15][16]. The Tb 3+ incorporation does not alter to the peak position/shape of each emission band, but the emission intensity increases with the Tb 3+ increasing until x=0.07 and then decreases owing to the concentration quenching.…”