The Role of the Eu3+ Concentration on the SrMoO4:Eu Phosphor Properties: Synthesis, Characterization and Photophysical Studies

Abstract

SrMoO(4) doped with rare earth are still scarce nowadays and have attracted great attention due to their applications as scintillating materials in electro-optical like solid-state lasers and optical fibers, for instance. In this work Sr(1-x)Eu(x)MoO(4) powders, where x=0.01; 0.03 and 0.05, were synthesized by Complex Polymerization (CP) Method. The structural and optical properties of the SrMoO(4):Eu(3+) were analyzed by powder X-ray diffraction patterns, Fourier Transform Infra-Red (FTIR), Raman Spectroscopy, and through Photoluminescent Measurements (PL). Only a crystalline scheelite-type phase was obtained when the powders were heat-treated at 800 °C for 2 h, 2θ=27.8° (100% peak). The excitation spectra of the SrMoO(4):Eu(3+) (λ(Em.)=614 nm) presented the characteristic band of the Eu(3+5)L(6) transition at 394 nm and a broad band at around 288 nm ascribed to the charge-transfer from the O (2p) state to the Mo (4d) one in the SrMoO(4) matrix. The emission spectra of the SrMoO(4):Eu(3+) powders (λ(Exc.)=394 and 288 nm) show the group of sharp emission bands among 523-554 nm and 578-699 nm, assigned to the (5)D(1)→(7)F(0,1 and 2) and (5)D(0)→(7)F(0,1,2,3 and 4), respectively. The band related to the (5)D(0)→(7)F(0) transition indicates the presence of Eu(3+) site without inversion center. This hypothesis is strengthened by the fact that the band referent to the (5)D(0)→(7)F(2) transition is the most intense in the emission spectra.