Luminescence studies on SrMgAl10O17:Eu, Dy phosphor crystals

Using urea as fuel, SrMgAl10O17:Eu, Dy phosphor was prepared by a combustion method. Its luminescence properties under ultraviolet (UV) excitation were investigated. Pure SrMgAl10O17 phase was formed by urea-nitrate solution combustion synthesis at 550 °C. The results indicated that the emission spectra of SrMgAl10O17:Eu, Dy has one main peak at 460 nm and one shoulder peak near 516 nm, which are ascribed to two different types of luminescent Eu2+ centers existing in the SrMgAl10O17 matrix crystal. The blue luminescence emission of SrMgAl10O17:Eu phosphors was improved under UV excitation by codoping Dy3+ ions. The SrMgAl10O17:Eu phosphors showed green afterglow (λ=516 nm) when Dy3+ ions were doped. Dy3+ ions not only successfully play the role of sensitizer for energy transfer in the system, but also act as trap levels and capture the free holes in the spinel blocks.