Quenching Study on iron impurity in Eu2+, Dy3+ Doped Strontium Aluminate Phosphor Prepared by Nano-Coating Process

摘要

A series of long afterglow phosphors, Eu<'2+>, Dy<'3 +>, with different iron content were prepared by nano-coating process. The resulted precursors were characterized by Transmission Electron Microscope (TEM), which suggested that the precursor particles had nanometer size distribution. The optical quenching of iron impurity on the phosphor powders were investigated by X-Ray powder Diffraction (XRD) and photoluminescence methods. The XRD indicates that a pure monoclinic SrAl<,2>O<,4>: Eu<'2+>, Dy<'3+> was formed at 1200℃ and iron impurity up to 296.36× 10<'- 4>% had no effect on the SrAl<,2>O<,4>: Eu<'2+>, Dy<'3+> phase structure. However, the luminescence intensity were strongly dependent on the trace iron impurity, which might be explained that iron displace the aluminium and form Fe-O bond, which competed energy with Eu<'2+> and transfer red them to infrared sites.