Structure, thermal and luminescence properties of Eu/Tb(BA)3phen/PAN fibers fabricated by electrospinning

Novel high luminescence fibers often exhibit potential applications in the fields of color displays and sensor systems. In this study, Eu(BA)3phen and Tb(BA)3phen powders was successfully synthesized by solvothermal reactions, firstly. Then, three kinds of novel flexible Eu(BA)3phen/PAN, Tb(BA)3phen/PAN and Eu/Tb(BA)3phen/PAN (BA = benzoic acid, phen = phenanthroline, PAN = Polyacrylonitrile) fibers had been successfully prepared by electrospinning technology. The characterizations of the final products have been investigated in detail. It was found that the diameter of the as-prepared fibers were almost uniform with the fabricated complexes doping into PAN successfully. Thermogravimetric analysis indicates that the thermal stability of the pure PAN fiber could be improved by the incorporation of the complex, although only 1 wt % was added. Furthermore, in Eu/Tb(BA)3phen complex, the fluorescence intensity of Eu3+ ions was remarkably increased by adding Tb3+ ions. This is primarily due to an energy transfer from the 5D4 level of Tb (III) to the 5D0 level of Eu (III) ions, where Tb3+ acted as sensitizer. The corresponding luminescent fibers displayed the same regularity as the complexes. Moreover, with the increasing of the incorporation of complexes into PAN, the fluorescence intensities were significantly enhanced and reached its maximum value at 2.5 wt % for Eu(BA)3phen/PAN fibers and 2.0 wt% for Tb(BA)3phen/PAN fibers. The further intensity decreased with the increasing content of the complexes because of typical emission concentration quenching.