Cation disorder in the phosphor lattice could be one of the effective approaches to modify the luminescence efficiency. In this work, cation substitutions of (Mo⁶⁺ → V⁵⁺) and (Na⁺ → Mg²⁺) were conducted in the self-activated NaMg₂V₃O₁₀. All the samples of Na_1+xMg_2−xV_3−xMo_xO₁₀ (x = 0, 0.01, 0.05, 0.1, 0.2, 0.3) were prepared via solid-state reaction. The morphological properties were measured via SEM and EDS analyses. Structural Rietveld refinement was performed to investigate the microstructure in the lattices. The cation substitution brings about structural disorder in the phosphor, which exerts great modifications in the luminescence properties. NaMg₂V₃O₁₀ presents an intrinsic indirect transition with a band gap of 3.22 eV. The incorporation of Mo⁶⁺ and Na⁺ in the lattices moves the optical absorption to a longer wavelength bringing about a narrower band gap. The luminescence intensity, thermal stability and corresponding lifetime were modified by the cation disorder in the self-activated phosphor.

中文翻译：

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在自激活的NaMg ₂ V ₃ O _10中通过诱导的阳离子紊乱改变 光学性质

磷晶格中的阳离子无序可能是改变发光效率的有效方法之一。在这项工作中，在自活化的NaMg ₂ V ₃ O ₁₀中进行了（Mo ⁶⁺ →V ⁵⁺）和（Na ⁺ →Mg ²⁺）的阳离子取代。通过固相反应制备Na _{1+ x} Mg _{2- x} V _{3- x} Mo _x O ₁₀（x = 0、0.01、0.05、0.1、0.2、0.3）的所有样品。形态学特性通过SEM和EDS分析。进行结构Rietveld精修以研究晶格中的微观结构。阳离子取代引起磷光体中的结构紊乱，这对发光性能产生了很大的影响。NaMg ₂ V ₃ O ₁₀呈现固有的间接跃迁，带隙为3.22 eV。Mo ⁶⁺和Na ⁺在晶格中的结合将光吸收移至更长的波长，从而带来较窄的带隙。发光强度，热稳定性和相应的寿命因自激活磷光体中的阳离子紊乱而改变。