Synthesis, structure, and luminescence properties of a new Eu 3+ -doped Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O oxyapatite red phosphor

A series of Eu 3+ -doped Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O red phosphors with apatite structure have been synthesized via high-temperature solid-state method. It could be concluded from XRD results that pure Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O: Eu 3+ phase was obtained. The structure refinement results confirmed that the space group of Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O: Eu 3+ was P 63 / m and Eu 3+ tended to replace some of Tb 3+ in [Ca 0.573 Tb 0.427 O 9 ] . Morphology and structural analysis were carried out by scanning electron microscopy (SEM), high transmission electron microscope (HTEM), selected area electron diffraction (SAED), Fourier transform infrared (FTIR), and Raman spectroscopy. The strongest emission peak of the emission spectrum under 259 nm excitation was located at 614 nm, which corresponded to the characteristic emission peak of Eu 3+ . When the doping concentration of Eu 3+ was higher than 0.8 mol%, the concentration quenching effect occurred. Tb 3+ ions served as the sensitizer transferred the absorbed energy to Eu 3+ ions effectively with the maximum transfer efficiency of 89.36%. The temperature-dependent photoluminescence emission spectra exhibited it possessed good thermal stability. The fabricated LED device combining Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O: 0.8 molEu 3+ with a 265 nm UV chip emitted brilliant red light. Ca 3 Tb 7 (BO 4 )(SiO 4 ) 5 O: Eu 3+ provided a new choice for red phosphors used in w-LEDs.