Structural and down-conversion luminescence of Ce³⁺ and Yb³⁺ doped NaY(MoO₄)₂ phosphor

Novel efficient visible and near-infrared emitting phosphors NaY(MoO₄)₂(NYM):Ln³⁺ (Ln = Ce and Yb) were proposed in this work. The crystal structure, lattice vibration characteristics, morphology, and luminescent properties of NaY(MoO₄)₂ phosphors were described. Sensitization of Ln³⁺ from the host with various doping concentrations was investigated. The yellow-green emission was achieved in Ce³⁺ single-doped NYM phosphors at UV ultraviolet excitation sensitized by the MoO₄²⁻ group. Under UV excitation, characteristic emissions of Ce³⁺ at 400–700 nm and Yb³⁺ at 1000 nm of NYM:Ce,Yb were observed, enabling the spectral down-conversion applications. With the increasing concentration of Yb³⁺, the emission intensity as well as the lifetime of Ce³⁺ decreased, confirming the energy transfer from Ce³⁺ ions to Yb³⁺ ions. And the energy transfer coefficient was 27% for NYM:0.01Ce,0.10Yb phosphor. These results indicate that the as-prepared phosphors have potential applications in optical and photonic devices.