Novel temperature-sensitive luminescent materials, Ba₂Gd₂Ge₄O₁₃ doped with Bi³⁺, Bi³⁺/Sm³⁺ or Bi³⁺/Eu³⁺ ions, have been prepared using a conventional solid-state reaction technique. The XRPD study has verified that all the synthesized germanates crystallize in the monoclinic system (space group C2/c, Z = 4). The crystal lattice of the compounds consists of zigzag chains of edge-sharing Me₂O₇ (Me = Bi³⁺, Eu³⁺ or Sm³⁺) dimers, [Ge₄O₁₃] units, and ten-coordinated Ba atoms. Under UV excitation the powders exhibit the luminescence corresponding to the ³P₁ → ¹S₀ (310–550 nm) transition in Bi³⁺ and ⁴G_5/2 → ⁶H_J (550–730 nm) in Sm³⁺ or ⁵D₀ → ⁷F_J (570–720 nm) transitions in Eu³⁺ ions. Heating of Ba₂Gd_1.94Bi_0.01Sm_0.05Ge₄O₁₃ and Ba₂Gd_1.89Bi_0.01Eu_0.1Ge₄O₁₃ phosphors leads to an irregular decrease in the intensity of the main emission lines. It has been found that the fluorescence intensity ratio between a wide band in the 310–530 nm region and peaks at longer wavelengths may be successfully used as a temperature-dependent characteristic. Absolute/relative sensitivity values for Ba₂Gd_1.94Bi_0.01Sm_0.05Ge₄O₁₃ and Ba₂Gd_1.89Bi_0.01Eu_0.1Ge₄O₁₃ germanates reach 0.19% K⁻¹/0.80% K⁻¹ and 2.21% K⁻¹/0.58% K⁻¹, respectively. The above parameters indicate that Ba₂Gd₂Ge₄O₁₃:Bi³⁺/Sm³⁺ or Bi³⁺/Eu³⁺ samples can be used as potential luminescent materials for non-contact temperature measurement.

中文翻译：

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Bi3+/Sm3+ 或 Bi3+/Eu3+ 共掺杂 Ba2Gd2Ge4O13 荧光粉的颜色可调发光和温度传感特性

采用常规固相反应技术制备了掺杂Bi ³⁺、Bi ³⁺ /Sm ³⁺或Bi ³⁺ /Eu ³⁺离子的新型温敏发光材料Ba ₂ Gd ₂ Ge ₄ O ₁₃ 。 XRPD研究证实所有合成的锗酸盐均在单斜晶系（空间群C 2/ c，Z = 4）中结晶。该化合物的晶格由共边Me ₂ O ₇ (Me = Bi ³⁺、Eu ³⁺或Sm ³⁺ )二聚体、[Ge ₄ O ₁₃ ]单元和十配位Ba原子的Z字形链组成。在紫外激发下，粉末表现出与 Bi ^3+中的3 P ₁ → ¹ S ₀ (310–550 nm) 跃迁和Sm ^3+中的4 G _5/2 → ⁶ H _J (550–730 nm)跃迁相对应的发光，或Eu ³⁺离子中的⁵ D ₀ → ⁷ F _J (570–720 nm) 跃迁。 Ba ₂ Gd _1.94 Bi _0.01 Sm _0.05 Ge ₄ O ₁₃和Ba ₂ Gd _1.89 Bi _0.01 Eu _0.1 Ge ₄ O ₁₃磷光体的加热导致主发射线的强度不规则降低。研究发现，310-530 nm 区域的宽带与较长波长的峰值之间的荧光强度比可以成功地用作温度依赖性特性。 Ba ₂ Gd _1.94 Bi _0.01 Sm _0.05 Ge ₄ O ₁₃和 Ba ₂ Gd _1.89 Bi _0.01 Eu _0.1 Ge ₄ O ₁₃锗酸盐的绝对/相对灵敏度值达到 0.19% K ^-1 /0.80% K ^-1和 2.21% K ^-1分别为/0.58% K ^-1。上述参数表明Ba ₂ Gd ₂ Ge ₄ O ₁₃ :Bi³⁺ /Sm ³⁺或Bi ³⁺ /Eu ³⁺样品可用作非接触温度测量的潜在发光材料。