Spectral properties and self-reduction of Eu to Eu in aluminosilicate oxyfluoride glass.

Eu-doped aluminosilicate oxyfluoride glass prepared a melt-quenching method was investigated using X-ray diffraction, absorption spectroscopy, X-ray fluorescence spectrometry, photoluminescence spectroscopy and fluorescence decay curves. We found that the reduction of Eu to Eu ions occurred in the glass prepared in air. The emission spectra showed that the intensity of 4f5d → 4f transition of Eu ions varied with increasing incident beam wavelength. Meanwhile, the fluorescence lifetimes of Eu: D → F monitored at 617 nm in the glass change with the variation of excitation wavelength. The energy transfer between Eu and Eu and the emission mechanisms of Eu ions in the glass were also discussed.