Optical properties of NaY(MoO4)2:Eu3+ nanophosphors prepared by molten salt method

Abstract

We synthesized NaY(MoO4)2:Eu3+ phosphors of different doping concentrations by a molten salt method. This facile way possesses advantages such as simple process, lower calcination temperature (350 °C) and small particle size (70 nm). The crystal system is tetragonal phase and crystal lattice is body centered. The photoluminescence measurements including emission spectra, excitation spectra and fluorescence decay curves were carried out, elucidating that NaY(MoO4)2:Eu3+ can be effectively excited by near UV and blue light. Moreover, it can be concluded that Eu3+ energy transfer type is exchange interaction. Huang-Rhys factor and the critical energy transfer distance (Rc) were calculated to be 0.043 and 0.995 nm, respectively. Auzel's model was used to obtain the intrinsic radiative transition lifetime of 5D0 level (τ0 = 0.923 ms). Furthermore, a calculation method was used to calculate refractive index n of nontransparent NaY(MoO4)2:1 mol% Eu3+ phosphor, and n was obtained to be 1.86.