Morphology and spectral characteristics of a luminous fiber containing a rare earth strontium aluminate

Abstract

The long afterglow strontium aluminate phosphor SrA l2 O 4 : Eu 2+ , Dy 3+ was prepared by a solid-state reaction method. The luminous fiber was prepared by melt spinning mixturing this complex and polyethylene terephthalate. The morphology and optical properties of the products had been characterized. Scanning electron microscope photographs indicated that rare earth aluminate salts were distributed on the fiber surface. X-ray diffraction diffusion data revealed that the crystal lattice of the polymer had not been significantly affected by the presence of the phosphor. The excitation spectrum showed broad bands in the ultraviolet and visible regions, and emission spectrum of the luminous fiber was shown to be red-shifted with a peak at 550 nm compared with that of the phosphor at 520 nm. The afterglow intensity of the luminous fiber decayed over an extended period, following an initial sharp reduction. The chromaticity diagram revealed a significant difference in the intensity of the luminous fiber and the phosphor, but only a minor color difference between them. The breaking strength and elongation of the luminous fiber were slightly below those of a normal polyester fiber.