Hydrothermal Synthesis and Luminescent Properties of BiPO_4:Eu~(3+) Phosphors

摘要

In this study, BiPO_4:Eu~(3+) phosphors were synthesized by a facile hydrothermal route at different temperatures. The BiPO_4:Eu~(3+) particles were characterized by x-ray powder diffraction (XRD), infrared spectra, and luminescence spectroscopy. The XRD results reveal that the BiPO_4:Eu~(3+) particles present different phases for different hydrothermal temperatures. It is found that a hexagonal phase is formed at 100℃, which transforms to a low-temperature monoclinic phase (MP) when the hydrothermal temperature is increased to 150℃. This low-temperature MP transforms to high-temperature MP when the temperature is increased beyond 200℃. The luminescent properties of the BiPO_4:Eu~(3+) particles were studied using an excitation wavelength of 270 nm. The emission spectra display the bands associated with the ~5D_0 → ~7F_J (J = 1, 2, 3, and 4) electronic transitions of the Eu~(3+) cations. The intensity of the emission spectra increases with increasing hydrothermal temperature. These results demonstrate that BiPO_4:Eu~(3+) with different phases can be obtained through the hydrothermal method, which may enrich the solution chemistry for preparation of advanced materials with tailored functionality.