Color–tunable luminescence and energy transfer behaviors of Dy3+/Eu3+ co–doped SrLaMgTaO6 phosphors for solid state lighting applications

A series of color–tunable SrLa 0.93-y MgTaO 6 :0.07Dy 3+ , yEu 3+ phosphors were synthesized via solid–state reaction. The X–ray diffraction, diffuse reflectance spectra, luminescent spectra, lifetimes and thermal quenching were applied to characterize the obtained phosphors. The X–ray diffraction results revealed that the obtained phosphors possessed pure monoclinic phase. The band gap of SrLaMgTaO 6 was calculated from Vienna ab initio simulation package and diffuse reflectance spectra. The energy transfers from host to Dy 3+ and Eu 3+ ions were confirmed by the luminescence spectra. Furthermore, the SrLa 0.92 MgTaO 6 : 0.07Dy 3+ , 0.01Eu 3+ phosphor had excellent thermal stability, while the integrated PL intensity still kept about 83.34% at 150 °C of that measured at room temperature (30 °C). In addition, the warm and cold white light emission could be generated with different Eu 3+ contents. All the results of SrLa 0.93-y MgTaO 6 :0.07Dy 3+ , yEu 3+ phosphors show great potential as a single–phase white–emitting phosphor for solid state lighting applications.