Synthesis and luminescent properties of Eu3+-activated Na0.5Gd0.5MoO4: A strong red-emitting phosphor for LED and FED applications

A series of Eu3+-activated Na0.5Gd0.5MoO4 phosphors were prepared by a typical sol-gel method. The as prepared samples possessed a single tetragonal phase and consisted of closely-packed particles. Under the excitation of 395 nm, all the phosphors exhibited the characteristic emissions of Eu3+ ions corresponding to the D-5(0) -> F-7(J) transitions. The photoluminescence (PL) emission intensities were enhanced with the increment of Eu3+ ion concentration and the optimum doping concentration was 0.25 mol. The energy transfer mechanism between the Eu3+ ions was dominated by dipole-dipole interaction and the critical distance was found to be 8.45 angstrom. Furthermore, the temperature-dependent PL emission spectra suggested that the obtained phosphors had good thermal stability (60.4% of the initial intensity at 150 degrees C). In addition, the color purity, chromatic and cathodoluminescence (CL) properties of the Na0.5Gd0.5MoO4:0.25Eu(3+) phosphor were also investigated. The results indicated that the Eu3+-activated Na0.5Gd0.5MoO4 phosphors with excellent PL and CL properties may have potential applications in white light-emitting diodes and field-emission displays. (C) 2016 Elsevier B.V. All rights reserved.