Glass forming regions and concentration-dependent luminescence properties of Tb~(3+)-activated tellurium-lutetium-tungsten glasses

The glass-forming regions of tellurium-gadolinium-tungsten ternary system prepared at 1000 °C for 60 min were firstly determined. To improve density, the full replacement of lutetium for gadolinium to form Tb³⁺-activated tellurium-lutetium-tungsten glasses with the composition of 64TeO₂-20WO₃-(16–y)Lu₂O₃-yTb₂O₃ were designed for scintillation application. The concentration-dependent optical properties of Tb³⁺-activated tellurium-lutetium-tungsten glasses were fully investigated by transmittance, excitation and emission spectra, together with the luminescence decay curves. The energy transfer mechanism was discussed according to Huang's rule. The optimized 4 mol% Tb₂O₃ activated tellurium-lutetium-tungsten glasses with the density of 6.49 g/cm³ and the lifetime of 0.551 ms are developing to be suitable for the potential detection of slow events in the future work.