Luminescence properties of a novel yellow-emitting phosphor NaLaMgWO6:Dy3+

A series of NaLaMgWO6:Dy3+ phosphors were prepared by a conventional solid-state reaction method at high temperature. The phase structure, morphology, particle size distribution and concentration dependent luminescence properties of the phosphors were investigated for the first time. Upon excitation with UV (290 nm) and n-UV (388 nm), NaLaMgWO6:Dy3+ phosphor exhibited typical Dy3+ emission corresponding to the 4F9/2 → 6HJ (J = 15/2, 13/2, 11/2) transitions of Dy3+, in which the hypersensitive electronic dipole transition 4F9/2 → 6H13/2 (575 nm) was with strongest emission intensity leading to the yellow emission with the CIE chromaticity coordinates (0.441, 0.475). The optimal concentration of Dy3+ was found to be 8%. The luminescence decay lifetime for 4G5/2 → 6H13/2 transition of Dy3+ was of millisecond level and decreased with the increase in Dy3+ ion concentration. The obtained results indicated that NaLaMgWO6:Dy3+ phosphor could be a potential yellow emitting phosphor for possible application in w-LEDs.