Study On Fluorescent Nanofibers Of Rare Earth Complexes With Polycarbonyl Ligands

The preparations of 1,3-bis?4,4,4-trifluoro-1,3-dioxobutyl?-phenyl?BTP?and its complexes?Eu₂?BTP?₃?H₂O?₄and Eu₂?BTP?₃?Phen?₂?Phen=1,10-phenanthroline??were optimized.Different concentrations ofbis-?-diketonate complexes?Eu₂?BTP?₃?H₂O?₄andEu₂?BTP?₃?Phen?₂?weredopedintothe poly?methylmethacrylate??PMMA?,polyvinylpyrrolidone?PVP?and polyacrylonitrile?PAN?,respectively.After the electrospinning conditions were also optimized,a series of nanofibers were electrospin successfully.Various characterization techniques were employed to reveal the effects of Eu₂?BTP?₃?H₂O?₄and Eu₂?BTP?₃?Phen?₂ on the morphology?SEM?,thermal stability?TGA?and luminescence of composite nanofibers.SEM images ofthese nanofibers displayed that all of the nanofibers with smoothsurface and uniform diameter were randomly distributed.FT-IR spectra show both ofcomplexes were successfully doped into three polymer matrixes,respectively.The luminescent spectra of the composite nanofibers show strong characteristic emission of Eu³⁺ions?Em spectra?,indicated thatall of the polymer matrixes acting asco-sensitizersfor Eu³⁺ions?Ex spectra?.The luminescent spectraalso indicate that the luminescent intensity increased with growing concentration of complexes and decreased by concentration quenching.The red brightness variation of fluorescence microscopy images is consistent with conclusion of luminescent spectra.Simultaneously,incomparison with the precursor complexes,thecomplex nanofibershave a great improvementin thermal stability.Furthermore,the Judd-Ofelt theory and simulative constructions of the complexes are employed to explain the effects of the dispersion of Eu₂?BTP?₃?H₂O?₄and Eu₂?BTP?₃?Phen?₂and the interactions between the complexes and neighboring chain segments of the polymer matrixes?PMMA?.