Formation and down/up conversion luminescence of Ln 3+ doped NaY(MoO 4 ) 2 microcrystals

NaY(MoO(4))(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(NO(3))(3)/Na(2)MoO(4) and pH values of the resultant solutions. NaY(MoO(4))(2) was demonstrated to be a good host material for different lanthanide ions. In the up-conversion luminescence spectrum of NaY(MoO(4))(2):Yb(3+)/Er(3+) under 980 nm excitation, the green emissions ((2)H(11/2)/(4)S(3/2)→(4)I(15/2)) were observed and the red emission ((4)F(9/2)→(4)I(15/2)) almost disappeared. The CIE chromaticity coordinates of NaY(MoO(4))(2):Yb(3+)/Er(3+) were calculated to be (0.27, 0.65). In the up-conversion luminescence spectrum of NaY(MoO(4))(2):Yb(3+)/Tm(3+), the (1)G(4)→(3)H(6) as well as (3)F(3)→(3)H(6) emission was observed and the CIE chromaticity coordinates of NaY(MoO(4))(2):Yb(3+)/Tm(3+) were calculated to be (0.25, 0.24). The down-conversion luminescence properties of NaY(MoO(4))(2):Eu(3+) were studied in detail. In addition, the decay lifetimes at the (4)S(3/2) (Er(3+)), (1)G(4) (Tm(3+)), and (5)D(0) (Eu(3+)) states were determined to be 5.63 μs, 19.76 μs, and 487.39 μs, respectively.