Luminescence properties of NaY(MoO4)2: Eu3+ for near-UV based white LEDs

A series of single Eu3+ activated NaY(MoO4)2 were synthesized by a solid state reaction at 550 ℃ for 4 h, and their luminescent properties are investigated. Phase formation is determined by X-ray diffraction (XRD) in a Bruker AXS D8 advanced automatic diffractometer (Bruker Co., German) with Ni-filtered Cu Kα1 radiation (λ=0.154 nm). Steady time resolved luminescence spectra, and excitation and emission spectra are detected by a fluorescence spectrophotometer (Hitachi F-4600). Commission International de I'Eclairage (CIE) chromaticity coordinates of samples are measured by a PMS-80 spectra analysis system. The X-ray powder diffraction results show that there has no crystalline phase other than NaY(MoO4)2. NaY(MoO4)2: Eu3+ can create red emission under the 393 nm excitation, and the prominent luminescence in red (616 nm) is due to the 5D0-7F2 transition of Eu3+. The emission intensities of Eu3+ in NaY(MoO4)2 enhance with the increase of the impurity concentration, there is no concentration quenching effect, and the phenomena are proved by the decay curves of Eu3+. Moreover, when tuning the Eu3+ doping content, the CIE chromaticity coordinates of NaY(MoO4)2: Eu3+ are measured, and the corresponding results present that they locate in the red region. The results indicate that the phosphors may have the potential applications in white light emitting diodes. ©, 2015, Board of Optronics Lasers. All right reserved.