Preparation and Luminescence Properties of YVO₄:Ln and Y(V, P)O₄:Ln (Ln = Eu³⁺, Sm³⁺, Dy³⁺) Nanofibers and Microbelts by Sol−Gel/Electrospinning Process

One-dimensional YVO 4:Ln and Y(V, P)O 4:Ln nanofibers and quasi-one-dimensional YVO 4:Ln microbelts (Ln = Eu 3+, Sm 3+, Dy 3+ ) have been prepared by a combination method of sol−gel process and electrospinning. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric and differential thermal analysis (TG−DTA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), low-voltage cathodoluminescence (CL), and time-resolved emission spectra as well as kinetic decays were used to characterize the resulting samples. Due to an efficient energy transfer from vanadate groups to dopants, YVO 4:Ln phosphors showed their strong characteristic emission under ultraviolet excitation (280 nm) and low-voltage electron beam excitation (1−3 kV). The energy transfer process was further studied by the time-resolved emission spectra as well as kinetic decay curves of Eu 3+ upon excitation into the VO 4 3− ion. Furthermore, the PL emission color of YVO 4:Ln nanofibers can be tuned from blue to green, orange-red, and red easily by partial replacement VO 4 3− with PO 4 3− and changing the doping concentrations ( x ) of Ln, making the materials have potential applications in fluorescent lamps and field emission displays (FEDs).