Scintillation properties of Tb³⁺ and Sn²⁺ co-doped phosphate glasses

Melt-quenched phosphate glasses prepared with fixed Tb³⁺ content alongside SnO added up to 5.0 mol% were characterized by density and optical absorption measurements, and radioluminescence (RL) evaluated under continuous X-ray excitation including at high temperatures. The densities exhibited some variations which were suggested to be influenced by the Sn⁴⁺ concentration leading to more compact phases. The optical absorption spectra were consistent with Tb³⁺ occurring similarly in the glasses. Comparison of the RL spectra at room temperature showed the most intense emission was obtained for the Tb-doped glass prepared with the highest SnO content supporting a key role from Sn²⁺ → Tb³⁺ energy transfer. An enhancement of the peak intensity of 2.5 × was observed, endorsing codoping with Sn²⁺ as an effective strategy to enhance the scintillator behavior of Tb³⁺-containing glasses. The temperature dependence of the scintillation spectra showed minimal variations for the tin-free Tb-doped reference, whereas the tin-containing glasses exhibited distinct intensity enhancements with temperature followed by quenching which depended on the SnO content.