Synthesis and characterization of needle-like BaAl2O4:Eu,Dy phosphor via

A needle-like Eu2+ and Dy3+ co-doped BaAl2O4 long-lasting phosphor was synthesized via a hydrothermal-homogeneous precipitation method assisted by cetyl trimethyl ammonium bromide (CTAB) as a template. The crystal structure, morphology and optical properties of the composites were characterized. XRD results showed that the single-phase BaAl2O4 was formed at 900 °C in an active carbon atmosphere, which was much lower than that prepared by traditional solid-state reaction method. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation revealed that the precursor had well-dispersed distribution and showed needle-like morphology with the average diameter of about 100 nm and the length up to 1 μm. The final product, BaAl2O4:Eu2+,Dy3+ phosphor, inherited the needle-like shape from precursor via adding the surfactant CTAB. After irradiation by ultraviolet radiation with 355 nm for 5 min, the phosphors emitted bluish green color long-lasting phosphorescence corresponding to the typical emission of Eu2+ ion. Both the photoluminescence spectra and luminance decay revealed that the phosphor had efficient luminescent and long-lasting properties.