Electrospinning preparation and luminescence properties of one-dimensional SrWO_4: Sm~(3+) nanofibers

摘要

One-dimensional Sm~(3+) doped SrWO_4 with or without different charge compensation approaches (co-doping Li~+, Na~+ and K~+) nanofibers were prepared by electrospinning. The structure, morphology and luminescence properties of the obtained nanofiber phosphors were investigated. The X-ray diffraction, Fourier transformation infrared and thermogravimetric results show that the Sr_((1-x))WO_4: Sm_x~(3+) samples crystallize at 700 ℃. Scanning electron microscope results indicate that as prepared nanofibers before/after calcination present uniform fiber-like morphology. The luminescence results show that Sr_((1-x))WO_4: Sm_x~(3+) phosphors can be excited efficiently by ultraviolet (UV) and near-UV light. The emission spectrum consists of three emission peaks at 561, 596 and 643 nm, corresponding to ~4G_(5/2) → ~6H_(5/2), ~4G_(5/2) → ~6H_(7/2) and ~4G_(5/2) → ~6H_(9/2) transitions of Sm~(3+), respectively. The optimal doping concentration of Sm~(3+) in SrWO_4 is experimentally ascertained to be 4 mol%. The introduction of charge compensator R~+ (R = Li, Na and K) can enhance the emission intensity of phosphors significantly. The co-doping of Li~+ has the best compensation effect. The present investigation indicates that Sm~(3+) doped SrWO_4 is a promising orange phosphor for light-emitting diode based on UV chip technology.