Luminescence and radiation response of Al2O3:Sb

A review of the literature on previous attempts to engineer the luminescence of Al₂O₃ for radiation dosimetry is presented followed by the investigation of Sb³⁺ as a new recombination center for Al₂O₃. Materials were prepared by solution combustion synthesis, calcined in air at 1050 °C, and characterized by X-ray diffraction (XRD) and Raman spectroscopy. They were determined to be single alpha phase up to a Sb concentration of 0.5 mol% when the gamma phase was also observed. Luminescence under X-ray excitation showed the presence of an intense band around 411–423 nm, depending on the Sb concentration, not observed in undoped Al₂O₃. Under excitation at 343 nm, the photoluminescence lifetime was estimated to be ∼11 μs. The lifetime together with the thermal quenching behavior demonstrated this band not to be from F centers and the emission was attributed to Sb³⁺. Sb-doped Al₂O₃ exhibited both optically stimulated (OSL) and thermoluminescence (TL) responses. The OSL initial intensity was nearly 5x more intense than undoped Al₂O₃. TL results indicated high sensitivity and showed a linear response to the irradiation dose at least up to 3 Gy.