Synthesis, characterization and luminescence property of ternary rare earth complexes with azatriphenylenes as highly efficient sensitizers

A series of novel ternary rare earth complexes showing attractive luminescence properties were prepared with both neutral and anion ligands. Three azatriphenylene neutral ligands, 1,10-phenanthroline (phen), dipyrido [3,2-a: 2′,3′-c] quinoxaline (dpq) and dipyrido [3,2-a: 2′,3′-c] phenazine (dppz) were investigated systematically as sensitizers in the ternary rare earth complexes. Benzoate ions (BA − ) and phenoxyacetate ions (POA − ) were chosen as anion ligands. The compositions of these complexes were characterized by elemental analysis, rare earth coordination titration, molar conductivity measurement, IR spectroscopy, UV–vis absorption spectroscopy, 1 H NMR spectroscopy and TGA–DTA. The luminescence spectra, luminescence decay time and quantum efficiency of the complexes were also studied. The very strong luminescence intensities and rather long luminescence lifetimes (typically > 1.0 ms) were achieved for both Eu 3+ and Tb 3+ ternary complexes with phen and dpq as neutral ligands. Moreover, high quantum efficiencies (40–60%) were also obtained for Eu 3+ ternary complexes with phen and dpq as neutral ligands.