Effects of bis(salicylidene)trimethylenediamine and 2,2′-bipyridyl on luminescence and extraction of tris(pivaloyltrifluoroacetonato)Eu(III)

The UV, excitation and luminescence spectra of EuA3B to be the extracted species as well as the extraction of Eu(III) with pivaloyltrifluoroacetone, HA, and/or Lewis bases, B (2,2′-bipyridyl, bpy, and bis(salicylidene)trimethylenediamine, H2saltn) into CHCl3 were measured. The results are summarized: the stability constants of EuA3bpy and EuA3H2saltn complexes are 5.85 ± 0.05 and 2.95 ± 0.06 as logβ¯1(β¯1=[EuA3B]o[EuA3]o-1[B]o-1), respectively. The present results suggest that because of intramolecular hydrogen bonding, the stability and luminescence of the H2saltn complex including the quantum yield are smaller than those of the bpy complex. The weaker luminescence is also concerned with the fact that the less stable complexes easily dissociate in solvents to diminish the essential concentration.

Based on the results of the study on solvent extraction and photophysical properties (UV, excitation/emission spectra, and quantum yields) of Eu(pta)3 complexes with bpy or H2saltn, it is concluded that the synergistic extraction would be an effective preparation method for useful phosphor. The method will expand the usage of solvent extraction. The excited (left) and luminescence (right) spectra of the mixed solutions containing EuA3 (6.5 × 10−5 M) and H2saltn (1. 7.2 × 10−4, 2. 1.3 × 10−4, 3. 0 M).Figure optionsDownload as PowerPoint slide