Hydrothermal synthesis and luminescent properties of NaLa(MoO4)2:Dy3+ phosphor

Pompon-like NaLa(MoO4)2:Dy3+ phosphors have been successfully prepared via a hydrothermal method using ammonia as pH value regulator. The hydrothermal process was carried out under aqueous condition without the use of any organic solvent, surfactant, and catalyst. The experimental results demonstrate that the obtained NaLa(MoO4)2:Dy3+ phosphor powders are single-phase scheelite structure with tetragonal symmetry. Moreover, the phosphor under the excitation of 390 and 456 nm exhibited blue emission (486 nm) and yellow emission (574 nm), corresponding to the 4F9/2→6H15/2 transition and 4F9/2→6H13/2 transition of Dy3+ ions, respectively. In addition, the yellow-to-blue emission intensity ratio (Y/B) can be changed with the doped concentration of Dy3+ ions. All chromaticity coordinates of the obtained NaLa(MoO4)2:Dy3+ phosphors are located in the white-light region. The results indicate that this kind of phosphor may has potential applications in the fields of near UV-excited and blue-excited white LEDs. - Graphical abstract: It can be seen from the SEM images that a pompon-like shape was obtained with an average diameter of about 1 μm, and it is composed of many nanoflakes. Highlights: ► Pompon-like NaLa(MoO4)2:Dy3+ phosphors have been successfully prepared via a hydrothermal method. ► Blue emission at 486 nm and yellow emission at 574 nm were obtained from the samples. ► The yellow-to-blue emission intensity ratio (Y/B) can be changed with the doped concentration of Dy3+ ions. ► NaLa(MoO4)2:Dy3+ can be efficiently excited by the blue light and the near ultraviolet light.