Photoluminescence and electron-beam excitation induced cathodoluminescence properties of novel green-emitting Ba4La6O(SiO4)6:Tb3+phosphors.

Tb 3+ ions activated Ba 4 La 6 O(SiO 4 ) 6 (BLSO:Tb 3+ ) phosphors were synthesized by a citrate sol-gel method. The X-ray diffraction pattern confirmed their oxyapatite structure. The field-emission scanning electron microscope image established that the BLSO:Tb 3+ phosphor particles were closely-packed and acquired irregular shapes. The photoluminescence (PL) excitation spectra of BLSO:Tb 3+ phosphors showed intense f–d transitions along with low intense peaks corresponding to the f–f transitions of Tb 3+ ions in the lower energy region. The PL emission spectra displayed the characteristic emission bands of Tb 3+ ions, and the optimized concentrations were found to be at 1 and 6 mol% for blue and green emission peaks, respectively. The cathodoluminescece (CL) spectra exhibited a similar behavior that was observed in the PL spectra except the intensity variations in the blue and green regions. The CL spectra of the BLSO:6 mol% Tb 3+ phosphor unveiled accelerating voltage induced luminescent properties. [ABSTRACT FROM AUTHOR]