Vol. 49, Issue 3, pp. 415-426 (2019)

Abstract

In this work, the fabrication of glass-ceramic materials containing MF₃:Eu³⁺ (M = La, Gd) nanocrystals dispersed in silica sol-gel hosts has been presented. The transformation from liquid sols towards bulk samples was also examined based on IR measurements. The crystallization temperatures and formation of MF₃ phases were verified based on TG/DSC analysis and XRD measurements. The optical properties of prepared Eu³⁺-doped samples were evaluated based on PLE and PL as well as luminescence decay analysis of the ⁵D₀ excited state. Obtained samples exhibit a series of the ⁵D₀ → ⁷F_J (J = 1–4) emission bands, which were recorded within the reddish-orange spectral area under near-UV illumination (λ_exc = 393 nm). Recorded luminescence spectra and double-exponential character of decay curves for prepared glass-ceramic samples indicated the successful migration of Eu³⁺ dopant ions from amorphous silica framework to low-phonon energy MF₃ nanocrystal phases.