Original Articles
Wu Wen, Xuan Ya-wen and Yin Ji
Abstract
The Eu3+, Tb3+, Pr3+ ions activated SrMoO4 phosphors have been synthesized using a conventional solid-state reaction under the 600℃, starting from Eu2O3, Tb4O7, Tb 6O11 and (NH4)2MoO4 as raw materials. The crystal structures of the products are characterized by Powders X-ray Diffraction (XRD). The results indicated that the nanoparticles crystallized in a tetragonal system of scheelite type. The typical emission spectrum of Sr0.95MoO4:0.05Eu3+ phosphors consists of sharp lines peaking at 532, 553, 590, 611 and 649nm, which are assigned to 5D1 -7F1, 5D0 - 7F0, 5D0 - 7F1, 5D0 -7F2 and 5D0 -7F3 respectively. When the Tb3+ is doped, the emission spectra composed of four emission peaks located at 487, 543, 579, and 617 nm, which are ascribed to the 5D4→ 7F6, 5D4→ 7F5, 5D4→ 7F4 and 5D4→ 7F3 transitions of Tb3+. The characteristic green luminescence of the Sr0.95MoO4:0.05Pr3+component on excitation at 241nm was attributed to the 3P0 excited state of Pr3+. The most intense lines with maxima at 486 and 643 nm correspond to the 3P0-3H4 and 3P0-3F2 transitions respectively.