Investigation of Photoluminescence Properties and Random Lasing Behaviors in Dy³⁺-Doped Sr₂MgMoO₆ Phosphors

Lanthanide-doped phosphors are of importance in the practical applications. In this work, we investigated the photoluminescence properties and random lasing behaviors of Dy<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup>-doped Sr<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>MgMoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> phosphors synthesized by the high-temperature solid-state method. The SEM, XRD, and EDS with elemental mapping results reveal the successful fabricating of the high-quality Sr<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>MgMoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> phosphors and confirm the uniform distribution of constituent elements. Structural characterization through precise Rietveld refinement confirmed that the material crystallizes in a tetragonal system with space group I4/m (No. 87), and its refined lattice parameters are also determined. The effect of different Dy<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> doping concentrations on the luminescent properties was analyzed. The optimal doping concentration for achieving efficient luminescence is fixed at 0.08 mol%. Typical emission peaks centered at 484 nm, 576 nm, 656 nm, and 756 nm of Dy<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup> were observed under the blue light excitation. Additionally, random lasing phenomena were observed in the Sr<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>MgMoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> phosphors when excited with a 355 nm pulsed laser under varying pump power densities. The random lasing behaviours were confirmed by the emergence of narrow emission peaks with a narrow full width at half maximum (FWHM) and the dependence of the intensity on the excitation intensity. This work highlights the potential of Dy<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3+</sup>-doped Sr<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub>MgMoO<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">6</sub> phosphors as efficient luminescent materials and demonstrates their application in random lasing, which opens new possibilities for their use in optoelectronic and laser technologies.