Electrospinning preparation and properties of magnetic-photoluminescent bifunctional coaxial nanofibers

Europium complex Eu(BA)(3)phen (BA = benzoic acid) and ferroferric oxide nanoparticles were incorporated into poly vinylpyrrolidone (PVP) and electrospun into coaxial nanofibers with Fe3O4/PVP as core and Eu(BA)(3)phen/PVP as the shell. The morphology and properties of the final products were investigated in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and a fluorescence spectrometer. The core diameter was ca. 110 nm containing the magnetic nanoparticles and the shell thickness was ca. 90 nm. Fluorescence emission peaks of Eu3+ in the Fe3O4/PVP@Eu(BA)(3)phen/PVP coaxial nanofibers were observed and assigned to the transitions of D-5(0) -> F-7(0) (581 nm), D-5(0) -> F-7(1) (592 nm), D-5(0) -> F-7(2) (617 nm), and the D-5(0) -> F-7(2) hypersensitive transition at 617 nm was the dominant emission peak. Compared with Eu(BA)(3)phen/PVP nanofibers, the luminescent intensity of the Fe3O4/PVP@Eu(BA)(3)phen/PVP coaxial nanofibers was almost not weakened in spite of the existence of the non-luminescent Fe3O4/PVP core. The new type bifunctional magnetic-photoluminescent Fe3O4/PVP@Eu(BA)(3)phen/PVP coaxial nanofibers have potential applications in many fields due to their excellent magnetism and fluorescence.