Europium complexes with high total photoluminescence quantum yields in solution and in PMMA

摘要

We have prepared complexes of formula [Eu(β-diketonate)_3-(DPEPO)] and shown quantitative excited-state energy transfer from the ligands combined with efficient Ln luminescence leading to exceptionally-high total photoluminescence quantum yield of up to 80% in solution and in PMMA.rnLanthanide (Ln) ions have important technological uses in optical, optoelectronic, supramolecular, biological labeling and sensing applications due to their intense, narrow emission bands that show little dependence on the coordinated ligands. Typically, however, they exhibit low absorption coefficients and require sensitization with highly-absorbing antenna ligands to effectively utilize their luminescence properties. The intramolecular transfer of optical excitation energy from organic ligands results in emission bands due to electronic transitions between the 4f energy levels of the lanthanide. Such Ln complexes display large Stokes shifts (> 150 nm) and long luminescence lifetimes in the millisecond range.