Rare‐earth (RE) titanate pyrochlore with perovskite‐layered structure is a well‐known engineering material in applied in many field. In this work, a red‐emitting phosphor of Gd_2−xNa_xTi_2−2xSb_2xO₇:Eu³⁺ (x = 0‐0.5) was developed via cation substitutions of (Sb⁵⁺→Ti⁴⁺) and (Na⁺→Gd³⁺) in Gd₂Ti₂O₇. The motivation is based on the fact that the introduction of cation‐disorders has been regarded to be an effective approach for improving the luminescent efficiency and thermal stability of RE‐activated materials. All the samples were synthesized via facile solid‐state reaction method. The morphology properties were measured via SEM and EDS measurements. The structural Rietveld refinement was performed to investigate the microstructure in pyrochlore lattices. The luminescence properties of Gd_2−xNa_xTi_2−2xSb_2xO₇:0.15Eu³⁺ (x = 0‐0.5) has a strict dependence on the cation substitution levels. The band energy of Gd₂Ti₂O₇ is 2.9 eV with a direct transition nature. The incorporation of Sb⁵⁺ and Na⁺ in the lattices moves the optical absorption to a longer wavelength. The cation disorder results in significant improvements of luminescence intensity, excitation efficiency in the blue region, longer emission lifetime and thermal stability.

中文翻译：

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G烧绿石中通过阳离子取代衍生的Eu3 +活化（Na0.5Gd1.5）（TiSb）O7的高效红光荧光粉

具有钙钛矿层结构的稀土钛酸盐烧绿石是在许多领域中广泛应用的著名工程材料。在这项工作中， 通过（Sb ⁵⁺ →Ti ⁴）的阳离子取代，开发了Gd _{2− x} Na _x Ti _{2−2 x} Sb _{2 x} O ₇：Eu ³⁺（x = 0-0.5）的红色荧光粉。⁺）和（Na ⁺ →Gd ³⁺）在Gd ₂ Ti ₂ O _7中。其动机是基于以下事实：引入阳离子无序被认为是一种提高RE活化材料的发光效率和热稳定性的有效方法。所有样品均通过简便的固相反应方法合成。通过SEM和EDS测量来测量形态学性质。进行结构Rietveld精修以研究烧绿石晶格中的微观结构。Gd _{2− x} Na _x Ti _{2−2 x} Sb _{2 x} O ₇：0.15Eu ³⁺  （x  = 0-0.5）的发光特性严格依赖于阳离子取代水平。Gd的能带₂ Ti ₂ O ₇为2.9 eV，具有直接跃迁性质。在晶格中掺入Sb ⁵⁺和Na ⁺将光吸收移至更长的波长。阳离子无序导致发光强度，蓝色区域的激发效率，更长的发射寿命和热稳定性得到显着改善。