Electrospinning-derived Tb-2(WO4)(3):Eu3+ nanowires: energy transfer and tunable luminescence properties

One-dimensional Tb-2(WO4)(3) and Tb-2(WO4)(3):Eu3+ nanowires have been prepared by a combination method of sol-gel process and electrospinning. X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL), low voltage cathodoluminescence (CL) and time-resolved emission spectra as well as kinetic decays were used to characterize the resulting samples. The as-obtained precursor samples present fiber-like morphology with uniform size, and Tb-2(WO4)(3) and Tb-2(WO4)(3):Eu3+ nanowires were formed after annealing. Under ultraviolet excitation and low-voltage electron beams excitation into WO42- and the f-f transition of Tb3+, the Tb-2(WO4)(3) samples show the characteristic emission of Tb3+ corresponding to D-5(4)-F-7(6, 5, 4, 3) transitions due to an efficient energy transfer from WO42- to Tb3+, while Tb-2(WO4)(3):Eu3+ samples mainly exhibit the characteristic emission of Eu3+ corresponding to D-5(0)-F-7(0, 1, 2) transitions due to an energy transfer occurs from WO42- and Tb3+ to Eu3+. The increase of Eu3+ concentration leads to the increase of the energy transfer efficiency from Tb3+ to Eu3+. The PL color of Tb-2(WO4)(3):x mol% Eu3+ phosphors can be tuned from green to red easily by changing the doping concentration (x) of Eu3+, making the materials have potential applications in fluorescent lamps and color display fields.