The luminescence properties of Tb and Ce in Rare Earth Doped crystalline oxides largely depend on their relative concentrations: by increasing the dopant concentration, the luminescence profile changes from blue to green because of the energy transfer among centers. The kinetic properties of the luminescence of optically excited Terbium-Cerium co-doped Y2SiO5 sol-gel synthesized crystal powders have been investigated as a function of the Tb dopant concentration (Ce content fixed at 1% atomic). The interaction among different Tb emitting centers and their relation with Ce centers was explained within the Inokuti-Hirayama model for a dipole-dipole energy transfer mechanism in the low-middle Tb concentration range whilst the Forster-Dexter model was applied in the middle-high Tb concentration range. The kinetic model allows elucidating the role of sensitizer and activator ion as a function of Tb concentration, successfully estimating the energy transfer mechanism efficiency and calculating the critical Tb concentration.
Energy transfer mechanism between Ce and Tb ions in sol-gel synthesized YSO crystals / Chiriu, D.; Stagi, L.; Carbonaro, C. M.; Corpino, R.; Ricci, P. C.. - In: MATERIALS CHEMISTRY AND PHYSICS. - ISSN 0254-0584. - 171:(2016), pp. 201-207. [10.1016/j.matchemphys.2016.01.006]