YF3:Ln(3+) (Ln = Ce, Tb, Pr) submicrospindles: hydrothermal synthesis and luminescence properties

YF3:Ln(3+) (Ln = Ce, Tb, Pr) microspindles were successfully fabricated by a facile hydrothermal method. X-Ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), lifetimes, photoluminescence (PL) and low-voltage cathodoluminescence (CL) were used to characterize the resulting samples. The lengths and diameters of YF3: 0.02Ce(3+) microspindles are around 760 nm and 230 nm, respectively. Adding dilute acid and trisodium citrate (Cit(3-)) are essential for obtaining YF3 microspindles. A potential formation mechanism for YF3 microspindles has been presented. PL spectroscopy investigations show that YF3:Ce3+ and YF3:Tb3+ microcrystals exhibit the characteristic emission of Ce3+ 5d -> 4f and Tb3+ D-5(4) -> F-7(J) (J = 6-3) transitions, respectively. In addition, the energy transfer from Ce3+ to Tb3+ was investigated in detail for YF3:Ce3+, Tb3+ microspindles. Under the excitation of electron beams, YF3:Pr3+ show quantum cutting emission and YF3:Ce3+, Tb3+ phosphors exhibit more intense green emission than the commercial phosphor ZnO:Zn.