Synthesis and photoluminescence properties of novel red-emitting KBaLu (MoO4)(3):Eu3+ phosphors with high thermal stability and high color purity

摘要

In this paper, we reported on the photoluminescence properties of novel Eu3+-activated KBaLu(MoO4)(3) red-emitting phosphors. Under 395 and 465 nm excitations, the as-prepared samples gave bright sharp red emissions around 592, 615, 655, and 701 nm, corresponding to D-5(o) -> F-7(J) (J = 1, 2, 3, and 4) transitions of Eu3+ ions. The 615 nm red emission due to the D-5(0) -> F-7(2) transition was dominant in the emission spectra, indicating the Eu3+ ions occupied non-inversion centrosymmetric sites in KBaLu(MoO4)(3) host lattice. Eu3+ doping concentration dependent luminescence properties were studied, and the KBaLu(MoO4)(3):0.8Eu(3+) sample exhibited the strongest emission intensity. The CIE color coordinates and color purity of the optimal KBaLu(MoO4)(3):0.8Eu(3+) sample were determined to be (0.6655, 0.3311) and 96.7%, respectively. Besides, temperature-dependent emission spectra demonstrated that the KBaLu(MoO4)(3):0.8Eu(3+) phosphors also exhibited excellent thermal stability (I-423k/I-303k = 88%) with activation energy Delta E of 0.204 eV. These obtained results indicated that the newly discovered KBaLu(MoO4)(3):Eu3+ red phosphors were promising color converters for application in white light-emitting diodes and display devices.