Luminescence properties and energy transfer investigations of Ba 2 La 2.85- x Tb 0.15 Eu x (SiO 4 ) 3 F multicolor phosphor.

The Ba 2 La 2.85- x Tb 0.15 Eu x (SiO 4 ) 3 F (BLSOF:0.15Tb 3+ , x Eu 3+ ) multicolor phosphors with apatite structure were synthesized via the solid-state pathway. The crystal structure and luminescence properties of the phosphors were investigated by means of scanning electron microscopy (SEM), X-ray diffraction (XRD), Rietveld refinement, photoluminescence excitation (PLE) and photoluminescence (PL). The luminescence performance of the phosphor was optimum when the concentration of Tb 3+ was set to be 0.15 mol and the concentration of Eu 3+ was set to be 0.22 mol. Under the accurate excitation of 373 nm near ultraviolet (n-UV) light, the emitting color of the phosphors can be tuned from green to red with increasing Eu 3+ /Tb 3+ ratio. It was further proved that the quadrupole-quadrupole (q-q) interaction is responsible for the energy transfer (ET) in the BLSOF:0.15Tb 3+ , 0.22Eu 3+ phosphor. Owing to the excellent thermal quenching luminescence property, the BLSOF:0.15Tb 3+ , x Eu 3+ phosphor can be applied in n-UV white light emitting diodes (w-LEDs) and serve as the warm part of warm white light.