Applied Surface Science, Vol.307, 482-488, 2014
The effect of surface modification on Eu3+ luminescence in EuF3 nanoparticles
Reaction between Eu(NO3)3 and NH4F in aqueous media was applied to produce EuF3 doughnut-like aggregates with a diameter of 200-500 nm and thickness of 50-150 nm composed of nanoparticles with a mean diameter of 16 nm. The impregnation, sorption and mechanochemical treatment were used for surface modification of EuF3 doughnut-like particles with 1,10-phenanthroline and sodium dibenzoylmethanate which are sensitizing ligands for Eu3' luminescence. The data of transmission electron microscopy, elemental analysis, Fourier transform infrared spectroscopy, and luminescence spectroscopy have proved that the organic ligands are coordinated to surface Eu3' ions, forming surface complexes. The surface modification of the EuF3 nanoparticles with sodium dibenzoylmethanate and 1,10-phenanthroline leads to increase in the luminescence intensity at 612 nm (5D0 7F2 transition) in comparison with the luminescence intensity of the unmodified EuF3 nanoparticles. Energy transfer from the ligand to Eu3+ ion in the surface complexes makes a main contribution to this effect. 2014 Elsevier B.V. All rights reserved.
Keywords:Surface modification;Europium fluoride;Nanoparticles Luminescence Dibenzoylmethane Phenanthroline