Radiation induced luminescence properties of Eu-doped SiO2 glass synthesized by spark plasma sintering

Abstract

We successfully synthesized Eu-doped SiO2 glasses by the spark plasma sintering method, and the prepared glasses doped with various concentrations of Eu (0, 0.002, 0.020 and 0.200%) were studied for optical, dosimeter and scintillation characteristics. The undoped sample showed the luminescence possibly due to the oxygen vacancy in photoluminescence (PL) and scintillation. The Eu-doped samples indicated PL due to the 5d-4f transitions of Eu2+ characterized as a broad emission peaking at approximately 450 nm. In the scintillation, we observed the emission of Eu2+ and Eu3+. The PL and scintillation decay time constants ascribed to the emission from Eu2+ were 1.96–1.99 μs and 1.63–1.70 μs, respectively. In the synthesized samples, the 0.002% Eu-doped sample indicated the highest PL quantum yield of 68.6%. Moreover, the highest light yields among the present samples were 407 photons/MeV under 241Am α-ray exposure. The prepared samples showed relatively low afterglow level. The materials also exhibit thermally stimulated luminescence (TSL) properties with a major glow peak around 200 °C, and when the TSL spectra were observed after the irradiation of X-rays (10 Gy), we confirmed that the luminescence was ascribed to the transitions of Eu3+ in addition to Eu2+. Overall, the samples showed a high sensitive response of TSL which showed a linearity from 0.01 mGy to 100 mGy.