Gd₂(MoO₄)₃:Eu³⁺ red phosphors assigned to different crystal systems were prepared using a sol–gel method with ammonium molybdate, Gd₂O₃, and Eu₂O₃ as starting materials. X‐ray diffraction (XRD) patterns showed that when annealing temperature was 700°C or 800°C, Eu³⁺ doping concentration was the main factor affecting sample structure. When the Eu³⁺ doping concentration was 0–2.00 mol%, samples had a monoclinic structure, but when the Eu³⁺ doping concentration was increased to 4.00–10.00 mol%, the samples changed to a mixed crystal structure (with existence of both monoclinic and orthorhombic structures). When the annealing temperature was increased to 900°C, annealing temperature became the main factor affecting sample structure, that is sample structure did not change with change in Eu³⁺ doping concentration, and all samples could be assigned to the orthorhombic system. Change in structure also affected the luminescence properties of the samples. Gd₂(MoO₄)₃:Eu³⁺ phosphors with different crystal systems could be effectively excited by blue light (466 nm wavelength); red light at 614 nm wavelength gave better colour purity and color stability, corresponding to the Eu³⁺⁵D₀→⁷F₂ transition. Finally, when Eu³⁺ concentration was 0.02 mol, the luminescence intensity of the orthorhombic system was higher than that of the monoclinic system; when the concentration was 0.04 mol, the luminescence intensity of the mixed system was almost the same as that of the orthorhombic system.

中文翻译：

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具有高色纯度的Gd2（MoO4）3：Eu3 +红色荧光粉的制备和发光性能。

使用溶胶-凝胶法，以钼酸铵，Gd ₂ O ₃和Eu ₂ O ₃为起始原料，制备了分配给不同晶体系统的Gd ₂（MoO ₄）₃：Eu ³⁺红色荧光粉。X射线衍射（XRD）图谱表明，当退火温度为700°C或800°C时，Eu ³⁺掺杂浓度是影响样品结构的主要因素。当Eu ³⁺掺杂浓度为0-2.00 mol％时，样品具有单斜晶结构，而当Eu ³⁺掺杂浓度增加到4.00–10.00 mol％，样品变为混合晶体结构（同时存在单斜晶和正交晶结构）。当退火温度升至900°C时，退火温度成为影响样品结构的主要因素，即样品结构不随Eu ³⁺掺杂浓度的变化而变化，所有样品均可归入正交晶系。结构的变化也影响了样品的发光性质。Gd ₂（MoO ₄）₃：Eu ³⁺蓝光（466 nm波长）可以有效激发具有不同晶体系统的磷光体；波长为614 nm的红色光具有更好的颜色纯度和颜色稳定性，对应于Eu ^{3 + 5} D ₀ → ⁷ F ₂跃迁。最后，当Eu ³⁺浓度为0.02 mol时，斜方晶系的发光强度高于单斜晶系的发光强度。当浓度为0.04mol时，混合体系的发光强度几乎与正交晶系的相同。