Tunable and enhanced simultaneous magnetism-luminescence bifunctionality assembled into a coaxial nanofiber
Abstract
[CoFe2O4–PVP]@[(Y(NO3)3 + Tb(NO3)3 + Al(NO3)3)–PVP] composite coaxial nanofibers have been successfully fabricated via electrospinning technology using a homemade coaxial spinneret. A new structure of CoFe2O4@YAG:Tb3+ magnetic-luminescent bifunctional coaxial nanofibers is obtained by calcination of the prepared electrospun composite coaxial nanofibers. The morphologies, structures, magnetic and luminescence properties of the final products were investigated in detail by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), fluorescence spectroscopy and vibrating sample magnetometry (VSM). The results show that the CoFe2O4@YAG:7%Tb3+ magnetic-luminescent bifunctional coaxial nanofibers simultaneously possess superior magnetic and luminescence properties due to isolation of the YAG:7%Tb3+ luminescence center from CoFe2O4 magnetic nanofibers. Furthermore, the luminescence intensity, color and saturation magnetization of the coaxial nanofibers can be tuned via adjusting the concentrations of rare earth ions and the amount of CoFe2O4 magnetic nanofibers. The bifunctional magnetic-luminescent CoFe2O4@YAG:7%Tb3+ coaxial nanofibers have potential applications in biomedical areas, such as drug-delivery systems, cell labeling and separation, enhancement for magnetic resonance imaging and subsequent optical identification. More importantly, the design conception and construction technology can fit the elaboration of any other bifunctional coaxial nanofibers.