In this research, the effects of fluoride ions concentration on luminescence properties of Eu3+:PbF2 nanocrystals in silicate sol gel materials have been investigated. Optical and structural properties of Eu3+:PbF2 nanocrystals have been examined using X-ray diffraction analysis (XRD) and luminescence spectroscopy. Formation of the cubic beta-PbF2 nanocrystalline phase was confirmed. The crystal size was estimated using Scherrer's equation and Williamson-Hall formula. The optical behavior of Eu3+ ions in studied materials is strongly dependent on amount of incorporated fluorides in the host lattice and the optimal concentration about 3.0 mass. % give the more intense emission of Eu3+. The luminescence spectra showed the characteristic orange-red emission due to the D-5(0) -> F-7(1) and D-5(0) -> F-7(2) electron transitions, respectively. The luminescence intensity ratio R (I(D-5(0) -> F-7(2))/I(D-5(0) -> F-7(1))) and luminescence lifetimes for the D-5(0) excited state of Eu3+ ions were determined for each sample before and after heat treatment process. Obtained results indicate the partially incorporation of Eu3+ ions into beta-PbF2 nanocrystalline phase during ceramization process. (C) 2016 Elsevier B.V. All rights reserved.