Eu~(3+)-activated B_2O_3-GeO_2-RE_2O_3 (RE = Y~(3+), La~(3+) and Gd~(3+)) borogermanate scintillating glasses

摘要

Borogermanate scintillating glasses with composition of 25B_2O_3-40GeO_2-2Eu_2O_3-33RE_2O_3 (RE=Y, La and Gd) were synthesized by melt-quenching method. The effect of RE_2O_3 on the glass structure and performance including the density, transmittance aswell as luminescent properties under both ultraviolet (UV) and X-ray excitation were compared and studied systematically. The enhanced intensity of Eu~(3+) emission under X-ray excitation is remarkably higher than that under UV excitation. The temperature-dependent emission spectra in the 75-295 K temperature region reveal that the thermal quenching behavior of Eu~(3+) luminescence in Y2O3-based glass is slightly better than that in La_2O_3- orGd_2O_3-based one. The covalency property of EuO bond and the local environment of Eu~(3+) ions is evaluated by the values of Ω_t parameter by employing the Judd-Ofelt analysis. The possible interconnection among the covalency nature of EuO bond, the thermal quenching behavior of Eu~(3+) emission, and the thermal stability of the designed borogermanate scintillating is also discussed.