Fluorescence and the relevant factors of organized molecular films of a series of atypical amphiphilic β-diketone rare earth complexes

Abstract

A series of atypical amphiphilic rare earth complexes were fabricated into Langmuir-Blodgett (LB) films on a composite subphase containing two ligands and corresponding rare earth complexes. The LB films were studied by focusing on the fluorescence emission. Optimised fabrication conditions for high quality LB films of the complexes were described in detail. Influences of the ligands and the rare earth ions on the fluorescence intensity were investigated as a whole. The characteristic fluorescence peaks at 613.0, 648.0 and 545.0 nm were selected for detection of europium, samarium and terbium complexes, respectively. The influence of the ligands on the fluorescence intensity of the complexes was discussed on the viewpoint of ligand structure and the triplet energy level. For europium or samarium ion bounded by different β-diketone ligands, Eu(TTA) 3 Phen or Sm(TTA) 3 Phen emitted the most intense fluorescence in LB films. However, in terbium complexes Tb(TTA) 3 Phen emitted the weakest fluorescence. The influences of the rare earth ions on the fluorescence of rare earth complexes were discussed on the resonance energy levels. The influence of fluorescence emission by two compounds in adjacent LB layers were also studied.