Radiation response properties of Dy-doped B₂O₃–Al₂O₃–SrO glasses

Borate glasses are considered to be host materials for thermoluminescent phosphors owing to their high thermally-stimulated luminescence (TSL) sensitivity and low effective atomic number. Herein, we fabricated the Dy-doped B₂O₃–Al₂O₃–SrO glasses to develop the phosphors for radiation dosimetry, and investigated their photoluminescence (PL), scintillation and TSL properties, systematically. The Dy-doped samples showed clear emission peaks at 480 and 570 nm due to 4f-4f transitions of Dy³⁺ in PL, and the 0.5 % Dy-doped sample exhibited the highest quantum efficiency of 0.24 under excitation wavelength of 350 nm among the sample tested. The decay time constants of the Dy-doped samples were 0.25–0.84 ms, which were typical values for the 4f-4f transition of Dy³⁺. In scintillation, the Dy-doped samples showed emissions with sharp peaks at 480 and 570 nm with the decay time constants of 0.51–0.86 ms due the 4f-4f transitions of Dy³⁺. The scintillation intensity of the 0.5 % Dy-doped sample was the highest among the samples investigated. Furthermore, the Dy-doped samples exhibited TSL with a main glow peak at approximately 90 °C after X-ray irradiation of 10,000 mGy, and the dynamic range of the 0.1–1.0 % Dy-doped samples was found to be 0.1–10,000 mGy.