Multi-color tunable Ce3+-Mn2+ cooperative Y7O6F9 vernier phosphors

Ce3+-Mn2+-doped Y7O6F9 vernier phosphors composed of Y7(1-p-2q/3)Ce7pMn14q/3O6F9 (p = 0.005-0.1, q = 0-0.1) were prepared using a flux-assisted solid-state reaction. The X-ray diffraction patterns of the resultant phosphors were examined to index the peak positions. The photoluminescence (PL) excitation and emission spectra of the Ce3+-activated yttrium-oxyfluoride phosphors were clearly monitored with critical emission quenching as a function of Ce3+ content in the Y7(1-p-2q/3)Ce7pMn14q/3O6F9. After doping the Y7O6F9 structure with Ce3+ and Mn2+ activators, intense blue and green/orange emission lights were observed in the PL spectra under near-ultraviolet (NUV) excitation. The dependence of the luminescent intensity of the Mn2+ co-doped (q = 0, 0.01, 0.05, 0.1) host lattices on Ce3+ content (p = 0.05, 0.1) was also studied. Co-doping Mn2+ into the Ce3+-doped host structure enabled high energy transfer from Ce3+ to Mn2+; this energy transfer mechanism is discussed. Multi-color tunable blue, white, yellow, and green emission lights due to the Ce3+ and Mn2+ emitters were observed at room temperature. With these phosphors, the desired CIE values including emissions throughout multi-color regions of the spectra were achieved.