Formation and down/up conversion luminescence of Ln(3+) doped NaY(MoO4)(2) microcrystals

NaY(MoO4)(2) microcrystals with different morphologies including spherical, rhombic, sheet-like, and rectangular plate-like morphologies have been successfully synthesized via a simple hydrothermal method by varying the molar ratios of Y(NO3)(3)/Na2MoO4 and pH values of the resultant solutions. NaY(MoO4)(2) was demonstrated to be a good host material for different lanthanide ions. In the up-conversion luminescence spectrum of NaY(MoO4)(2):Yb3+/Er3+ under 980 nm excitation, the green emissions (H-2(11/2)/S-4(3/2) -> I-4(15/2)) were observed and the red emission (F-4(9/2) -> I-4(15/2)) almost disappeared. The CIE chromaticity coordinates of NaY(MoO4)(2):Yb3+/Er3+ were calculated to be (0.27, 0.65). In the up-conversion luminescence spectrum of NaY(MoO4)(2):Yb3+/Tm3+, the (1)G(4) -> H-3(6) as well as F-3(3) -> H-3(6) emission was observed and the CIE chromaticity coordinates of NaY(MoO4)(2):Yb3+/Tm3+ were calculated to be (0.25, 0.24). The down-conversion luminescence properties of NaY(MoO4)(2):Eu3+ were studied in detail. In addition, the decay lifetimes at the S-4(3/2) (Er3+), (1)G(4) (Tm3+), and D-5(0) (Eu3+) states were determined to be 5.63 mu s, 19.76 mu s, and 487.39 mu s, respectively.