Fabrication of fluoride nanocrystals and their spectroscopic properties.

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 7FJ (J = 1-4) emission bands, which were recorded within the reddish-orange spectral area under near-UV illumination (λexc = 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. [ABSTRACT FROM AUTHOR]