Surface radiation-regulation effect in Eu(BA)₃Phen doped polyacrylonitrile nanofibers

Electrospun nanofibers of Eu(BA)₃Phen doped polyacrylonitrile (PAN) have been prepared and the surface radiation-regulation effect of flexible fibers is revealed. Fluorescence contrast between bulks and nanofibers confirmed that the fibrosis process facilitated spectral reshaping and enhanced energy transfer efficiency of ligands to rare earth ions. Due to the enhanced surface radiation-regulation effect, the quantum efficiency of Eu(BA)₃Phen/PAN nanofibers remains on an upward tendency as Eu(BA)₃Phen content increasing, and the maximum quantum efficiency of fibers reaches to 86.7%. Large emission cross-section and high radiation transition probability for ⁵D₀ → ⁷F₂ of Eu³⁺ reach up to 4.043 × 10⁻²¹ cm² and 518.79 s⁻¹, respectively, which indicates that the europium-complexes/PAN nanofibers possess great emissive ability. Accordingly, the nano-sized rare-earth fluorescence materials with high quantum efficiency and excellent flexibility obtained by electrospun fibrosis compensate the brittle defects of bulks, which provides a breakthrough in developing light-converting materials.