Luminescence and energy transfer of rare-earth-metal ions in Mg2Y8(SiO4)6O2
Abstract
The photoluminescence of Ce3+, Tb3+ and Sm3+, and energy transfer from Ce3+ to Tb3+, Dy3+ and Sm3+ in Mg2Y8(SiO4)6O2 are reported and discussed. The Ce3+ ion shows blue luminescence under UV excitation, and occupies simultaneously the 4f site and 6h site in the host lattice. The optimum concentrations for the 5D3 and 5D4 emissions of Tb3+ and the 4G5/2 emission of Sm3+ are determined to be 0.04, 0.20 and 0.10 mol in every mol of Mg2Y8(SiO4)6O2, respectively. The critical distances responsible for the cross-relaxation between the 5D3–5D4 and 7F6–7F0 transitions of Tb3+ and between the 4G5/2–4F9/2 and 6H5/2–4F9/2 transitions of Sm3+ are estimated to be 1.43 and 1.06 nm, respectively. Both Tb3+ and Dy3+ can be sensitized by Ce3+, but Ce3+ and Sm3+ quench each other.