Fabrication and luminescence properties of one-dimensional CaMoO(4): Ln(3+) (Ln = Eu, Tb, Dy) nanofibers via electrospinning process.

One-dimensional CaMoO(4):Ln(3+) (Ln = Eu, Tb, Dy) nanofibers have been prepared by a combination method of sol-gel and electrospinning process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), and low voltage cathodoluminescence (CL) as well as kinetic decays were used to characterize the resulting samples. SEM and TEM analyses indicate that the obtained precursor fibers have a uniform size, and the as-formed CaMoO(4):Ln(3+) nanofibers consist of nanoparticles. Under ultraviolet excitation, the CaMoO(4) samples exhibit a blue-green emission band with a maximum at 500 nm originating from the MoO(4)(2-) groups. Due to an efficient energy transfer from molybdate groups to dopants, CaMoO(4):Ln(3+) phosphors show their strong characteristic emission under ultraviolet excitation and low-voltage electron beam excitation. The energy transfer process was further studied by the emission spectra and the kinetic decay curves of Ln(3+) upon excitation into the MoO(4)(2-) groups in the CaMoO(4):x mol % Ln(3+) samples (x = 0-5). Furthermore, the emission colors of CaMoO(4):Ln(3+) nanofibers can be tuned from blue-green to green, yellow, and orange-red easily by changing the doping concentrations (x) of Ln(3+) ions, making the materials have potential applications in fluorescent lamps and field emission displays (FEDs).