Study of the effect of ligands on the fluorescence properties of terbium ternary complexes

Abstract

Four ternary complexes of Tb(III) were synthesized by introducing the first ligand (L 1) ( N-phenylanthranilic acid (N-HPA), α-furoic acid (FURA)) and the second ligand (L 2) (1,10-phenanthroline (Phen), 2,2′-dipyridyl (Bipy)), respectively. These complexes were characterized by elemental analysis, infrared spectra, XRD, UV spectra and fluorescence spectra. The effect of L 1 and L 2 on the fluorescence properties of terbium complexes was discussed. It showed that all the complexes exhibited ligand-sensitized green emission. The fluorescent intensity increased in the sequence of Tb(FURA) 3Bipy < Tb(N-PA) 3Phen < Tb(FURA) 3Phen < Tb(N-PA) 3Bipy. It indicated that L 1 affected fluorescence properties of the complexes differently when the corresponding L 2 altered. Meanwhile, the influence of L 2 on the luminescence properties of the complexes also depends on L 1. The results showed that L 1 and L 2 affected each other and worked together as a whole. The matching of L 1, L 2 and Tb 3+ ion is very important to the luminescence properties of Tb(III) ternary complexes.