Eu3+-activated B2O3–GeO2–RE2O3 (RE = Y3+, La3+ and Gd3+) borogermanate scintillating glasses

Borogermanate scintillating glasses with composition of 25B(2)O(3)-40GeO(2)-2Eu(2)O(3)-33RE(2)O(3) (RE = Y, La and Gd) were synthesized by melt-quenching method. The effect of RE2O3 on the glass structure and performance including the density, transmittance as well as luminescent properties under both ultraviolet (UV) and X-ray excitation were compared and studied systematically. The enhanced intensity of Eu3+ 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 Eu3+ luminescence in Y2O3-based glass is slightly better than that in La2O3- or Gd2O3-based one. The covalency property of Eu-O bond and the local environment of Eu3+ ions is evaluated by the values of a parameter by employing the Judd-Ofelt analysis. The possible interconnection among the covalency nature of Eu-O bond, the thermal quenching behavior of Eu3+ emission, and the thermal stability of the designed borogermanate scintillating is also discussed. (c) 2014 Elsevier B.V. All rights reserved.