Luminescence properties and energy transfer investigations of BaLa TbEu (SiO)F multicolor phosphor.

The BaLa TbEu (SiO)F (BLSOF:0.15Tb, Eu) multicolor phosphors with apatite structure were synthesized 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 was set to be 0.15 mol and the concentration of Eu 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/Tb ratio. It was further proved that the quadrupole-quadrupole (q-q) interaction is responsible for the energy transfer (ET) in the BLSOF:0.15Tb, 0.22Eu phosphor. Owing to the excellent thermal quenching luminescence property, the BLSOF:0.15Tb, Eu phosphor can be applied in n-UV white light emitting diodes (w-LEDs) and serve as the warm part of warm white light.