Preparation, characterization and luminescence properties of pyrochlore La_2Zr_2O_7:Eu~(3+) nanofibers by electrospinning

摘要

One-dimensional Eu~(3+)-doped La_2Zr_2O_7 nanofibers were fabricated by a simple and effective electrospinning combined with sol-gel process. The structural properties were characterized by thermogravimetric and differential thermal analysis(TG-DTA), x-ray diffraction(XRD), field emission scanning electron microscope(FESEM), and energy-dispersive x-ray spectroscopy(EDS). XRD analysis indicates that La_2Zr_2O_7:Eu~(3+) nanofibers are pyrochlore in structure with space group Fd-3m. FESEM analysis indicates the surface of La_2Zr_2O_7:Eu~(3+) nanofibers is coarse, the average diameter is ca. 190nm. The photoluminescent(PL) properties of the La_2Zr_2O_7:Eu~(3+) nanofibers were also studied. It is observed that the charge-transfer excitation peak of Eu~(3+)-O~(2-) is 279 nm, absorption peak of La_2Zr_2O_7 matrix is 228 nm. Under excitation of 279nm, La_2Zr_2O_7:5%Eu~(3+) nanofibers emit the main emission at 587 nm, corresponding to ~5D_0-~7F_1 transition of Eu~(3+); under excitation of 228 nm, La_2Zr_2O_7:5%Eu~(3+) nanofibers emit the main emission at 580 nm, corresponding to 5D0-7F0 transition of Eu~(3+). Possible formation mechanism of La_2Zr_2O_7:Eu~(3+) nanofiber was proposed.