Photoluminescence and energy transfer mechanism in Y6Ba4(SiO4)6F2 apatite phosphors doped with cerium and terbium

Y6Ba4(SiO4)6F2 (YBSF) phosphors having apatite structure was doped with cerium and terbium and prepared by solid-state reaction method. Structural and photoluminescence properties of the prepared apatite phosphors were studied and discussed in detail. X-ray diffraction graph affirms that the prepared phosphor has hexagonal symmetry with space group P63/m, representing the apatite structure. Scanning electron microscopy reveals the morphology of the prepared phosphor and clearly shows an elongated rod-like structure. Energy dispersive X-ray spectroscopy pattern confirms the presence of all initial constituents in YBSF:0.6Ce3+, xTb3+. Fourier transform infrared spectroscopy study was conducted to identify various functional groups present in the prepared phosphors. Photoluminescence excitation and photoluminescence emission spectra of YBSF:0.8Tb3+ and YBSF:0.6Ce3+,xTb3+ (x = 0, 0.2, 0.4, 0.6, 0.8 and 1 mol%) were obtained and studied. Photoluminescence spectra successfully established the energy transfer mechanism working between Ce3+ and Tb3+ ions and the energy transfer efficiency was found to be 66%. Commission Internationale de I’Eclairage(CIE) chromaticity coordinate clearly shows the colour tenability property of YBSF:0.6Ce3+,xTb3+. The emitted light in YBSF:0.6Ce3+,xTb3+ depends on the concentration of Tb3+.