Preparation and fluorescent properties of terbium-complex/PVP electrospun fiber

The polyvinylpyrrolidone (PVP) fibers containing Tb(AA)₃Phen complexes were generated through electrospinning. The influence of different Tb(AA)₃Phen concentrations, voltage, ratios of the two solvents and the solution conductivity on the morphology of PVP fiber was investigated. The electrospun fibers with the diameter of 80~150 nm possessed smooth surface and uniform diameter distribution. The fluorescent spectra showed that the fluorescence intensity of Tb(AA)₃Phen/PVP fibers increased with increasing Tb(AA)₃Phen content and reached its maximal value at 15% (mass fraction). This was followed by emission concentration quenching with further increasing the Tb(AA)₃Phen content. The TEM observation and XRD analysis revealed that the Tb(AA)₃Phen dispersed in the PVP fibers in the state of molecular clusters or tiny particles (d<10 nm). Due to the fine dispersion of Tb(AA)₃Phen, the nonradiative transition rate of the fluorescent fibers decreased, which resulted in increased fluorescence intensity and fluorescence life of the fibers.