Development of YK3B6O12:RE (RE = Eu3+, Tb3+, Ce3+) tricolor phosphors under near-UV light excitation.

Polycrystalline phosphors YK 3 B 6 O 12 :RE 3+ (RE = Eu, Ce, Tb) were prepared by the solid-state synthesis. The single crystal-phases of the samples were confirmed by X-ray powder diffraction (XRD) measurements and the structural refinements. The field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and electron dispersive X-ray (EDX) measurements were applied to analyze the morphologies of the phosphors. The photoluminescence excitation spectra (PLE) and emission (PL) spectra, decay curves and lifetimes were investigated. Under the near-UV light excitation, YK 3 B 6 O 12 :Eu 3+ , YK 3 B 6 O 12 :Ce 3+ , and YK 3 B 6 O 12 :Tb 3+ phosphors exhibit the characteristic emission transitions from Ce 3+ (5d→4f transitions in blue color), Eu 3+ ( 5 D 0 → 7 F 2 , red color), and Tb 3+ ( 5 D 4 → 7 F 5 , green color), respectively. The luminescence internal quantum efficiency (QE), the optimal doping level and the thermal stability with the activation energy (Δ E ) were measured. The result in this work could be useful for the further applications of this new host as a potential phosphor. [ABSTRACT FROM AUTHOR]