Thermoluminescence properties of Tb³⁺-doped CaO–Al₂O₃–B₂O₃-based glasses

In this study, the thermoluminescence (TL) characteristics and X-ray radiation response properties of 35CaO–15Al₂O₃–50B₂O₃:xTb₄O₇ (x = 0.25, 0.5, 1.0, 2.0, and 4.0 mol%) glasses were evaluated. These glasses, prepared by a conventional quenching method, were transparent and non-hygroscopic. The TL spectra showed a green band emission (400–600 nm) arising from 4fⁿ–4fⁿ forbidden transitions of the Tb³⁺ ions. A TL glow peak was observed at 360 K in all the glasses at different Tb concentrations. Among them, the 1.0, 2.0, and 4.0 mol% Tb-doped glasses exhibited excellent linearity over the 1.0 mGy–10 Gy irradiation dose range. The TL peak intensity decreased to ∼60% after 1 h, ∼45% after 24 h and ∼30% after 72 h.