BaLu6(Si2O7)2(Si3O10):Ce3+,Tb3+: A novel blue-green emission phosphor via energy transfer for UV LEDs

Abstract

A series of novel blue-green emission phosphors BaLu6(Si2O7)2(Si3O10):Ce3+,Tb3+ (BLSO:Ce3+,Tb3+) were synthesized via the high-temperature solid-state reaction route. Many characterizations such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) were conducted to analyze the phase and structure of as-prepared samples. Photoluminescence (PL) properties illustrated that Ce3+ singly doped BLSO can produce a broad band ranging from 365 to 550 nm upon UV excitation, which overlapped the excitation spectrum of Tb3+ monitored at 550 nm emission. Energy transfer phenomenon from Ce3+ to Tb3+ in this kind of phosphor was demonstrated from the variations of emission spectra and the decrease of Ce3+ fluorescent decay lifetime in Ce3+-Tb3+ co-doped BLSO, based on which the emission color can be tuned from bright blue to green upon UV excitation. The energy transfer mechanism from Ce3+ to Tb3+ was determined to be electric dipole-quadrupole interaction. Moreover, the temperature-dependent PL of representative BLSO:0.18Ce3+,1.00Tb3+ was supplied in this manuscript, which indicated the good thermal stability of this kind of phosphor. The results show that BLSO:Ce3+,Tb3+ phosphors can be as a potential candidate of blue-green component in phosphor-converted UV LEDs.