Composite CaAl2O4-2CaAl4O7 : Re3+ (Re3+ = Tb3+, Sm3+) phosphors were prepared by the SPCS technique, which were studied via XRD, SEM, FT-IR spectra and luminescent spectra. The results show that the crystal lattice structure of them needs slight distortion to improve luminescence properties. They exhibit wider near-UV excitation band around 380 nm. Upon exciting with 380 nm, CaAl2O4-2CaAl4O7 : Tb3+ shows a strong green-light at 548 nm corresponding to a 5D4→ 7F5 transition of Tb3+ ions, and CaAl2O4-2CaAl4O7 : Sm3+ presents strong red-light at 604 nm corresponding to a 4G5/2→ 6H7/2 transition of Sm3+ ions. The product fired at 900 oC exhibit high quality crystallinity and with a size of that is approximately 1-3 μm. All the above characteristics of the products are beneficial for phosphors for white LEDs.

Keywords: SPCS, CaAl2O4-2CaAl4O7 : Re3+ (Re3+=Tb3+, Sm3+), luminescence properties, white LEDs.