Structural, optical and photoluminescent properties of Europium-doped potassium germanate glassy materials were investigated in terms of tantalum content and nanoscale crystallization of potassium tantalate K₂Ta₈O₂₁. For such purpose, an Eu³⁺-doped germanate glass, Eu³⁺-doped tantalum germanate glass and Eu³⁺-doped tantalum germanate glass-ceramics were prepared and characterized by X-ray diffraction, Raman, UV–Vis–NIR and photoluminescence spectroscopies. Eu³⁺ emission properties were used as a sensitive probe to investigate its symmetry site into the host structure. The chemical microenvironment around Eu³⁺ ions have changed with tantalum concentration as well as bronze-like tantalum perovskite K₂Ta₈O₂₁ phase crystallization into the glasses. The ions preferably occupy sites of higher symmetry and lower energy phonons, which attest the ions migration to the tantalum-rich crystalline environment. The correlation between the phonon side band (PSB) spectra and Raman vibrational modes, ⁵D₀ → ⁷F₂/⁵D₀ → ⁷F₁ ratio and experimental Eu^{3+ 5}D₀ lifetime support this assumption. The highest photoluminescence intrinsic quantum yield (${\text{Q}}_{\text{Eu}}^{\text{Eu}}$) is calculated for glass-ceramics heat-treated for 20 h by using Judd-Ofelt theory, indicating reduction of nonradiative decay processes due to the lower local phonon energy. The luminescence quenching for longer crystallization times demonstrates the importance of optimizing thermal treatment parameters to ensure proper distance between optically active ions. Accordingly, tantalum germanate glass-ceramics are promising for photonic devices as red laser, solid-state lighting and energy conversion applications, as well as for nonlinear optical applications considering the perovskite bronze-like crystallization.

在钽含量和钽酸钾 K ₂ Ta ₈ O _{21 的}纳米级结晶方面研究了铕掺杂的锗酸钾玻璃材料的结构、光学和光致发光特性。为此，制备了 Eu ³⁺掺杂的锗酸盐玻璃、Eu ³⁺掺杂的锗酸盐玻璃和 Eu ³⁺掺杂的锗酸盐玻璃陶瓷，并通过 X 射线衍射、拉曼、UV-Vis-NIR 和光致发光光谱。Eu ³⁺发射特性被用作敏感探针来研究其在主体结构中的对称位点。Eu ³⁺周围的化学微环境离子随着钽浓度的变化以及青铜状钽钙钛矿 K ₂ Ta ₈ O ₂₁相结晶到玻璃中而发生变化。离子优选占据较高对称性和较低能量声子的位置，这证明离子迁移到富含钽的晶体环境。声子边带 (PSB) 光谱与拉曼振动模式、⁵ D ₀ → ⁷ F ₂ / ⁵ D ₀ → ⁷ F ₁比率和实验 Eu ^{3+ 5} D _{0 之间的相关性}终生支持这个假设。最高的光致发光本征量子产率（${\text{问}}_{\text{欧洲联盟}}^{\text{欧洲联盟}}$) 是使用 Judd-Ofelt 理论对热处理 20 小时的玻璃陶瓷计算的，表明由于较低的局部声子能量，非辐射衰变过程减少。更长结晶时间的发光淬灭表明优化热处理参数以确保光学活性离子之间的适当距离的重要性。因此，锗酸钽玻璃陶瓷有望用于光子器件，如红色激光器、固态照明和能量转换应用，以及考虑钙钛矿青铜样结晶的非线性光学应用。