Site-selective luminescence of Nd3+ doped transparent oxyfluoride nano glass-ceramics

Abstract

In this work, transparent oxyfluoride glass-ceramics obtained by the adequate heat treatment of Nd 3+ -doped glass with composition SiO 2 -Al 2 O 3 -Na 2 O-LaF 3 are investigated. X-ray diffraction (XRD) and high resolution transmission electron microscopy (HR-TEM) show that the precipitated nanocrystals are LaF 3 with a crystal size between 9 - 12 nm. Site-selective and time-resolved emission and excitation spectra of the 4 F 3/2 and 4 F 5/2 states, allow to unambiguously isolate the emission of Nd 3+ ions in LaF 3 nanocrystals which shows extremely well defined spectra, similar to those obtained for pure LaF 3 crystal. As the Nd 3+ concentration is increased beyond 0.1 mol%, the luminescence quenching of lifetime for Nd 3+ ions inside LaF 3 crystals is observed to be stronger than for those dispersed in the glass matrix.