Mixed Anionic Metal Hydrides as Host Lattices for the Luminescence of Divalent Europium

无机主体晶格中的二价铕Eu（II）对于照明装置中的应用具有极大的兴趣。在氧化物基化合物和卤化物中，它通常在用UV光激发时显示蓝色或绿色发射（光致发光）。对于更可极化的配体，例如氮化物或氮化物，发射转变为黄色、橙子或红色。通过对混合阴离子双金属基质材料的研究，系统地分析了掺杂浓度、键长、氢化物配体数目、软硬阴离子的混合、配位数和对称性对发光性能的影响。这些材料将掺杂不同数量的铕（0.1-2%），并通过X射线衍射，中子衍射和发光光谱学进行表征，包括非常高的分辨率光谱，低温和寿命测量。氢化主体材料将来自各种类型的主要离子混合阴离子金属氧化物，例如，G.钙钛矿型氢化物氟化物KCaH 3-xFx（1识别和量化的晶体化学关键参数的Eu（II）发光在这样的化合物将使我们能够预测铕原子周围的理想化学环境，为选定的发射波长，建议合适的晶体结构，从而知识驱动的发光材料的发展。这将在一定程度上提供对混合阴离子金属氧化物中Eu（II）发光的深入理解，其中它可以用作寻找新发光材料的指导。

Divalent europium, Eu(II), in inorganic host lattices is of great interest for applications in lighting devices. In oxide based compounds and in halogenides, it usually shows blue or green emission upon excitation with UV light (photoluminescence). With more polarizable ligands, such as nitrides or hydrides, the emission shifts to yellow, orange or red. By investigating mixed anionic hydridic host materials, we want to systematize the influence of dopant concentration, bond length, number of hydride ligands, mixing of hard and soft anions, coordination number and symmetry on luminescence properties. These materials will be doped with different amounts of europium (0.1-2%) and characterized by X-ray diffraction, neutron diffraction and luminescence spectroscopy, including very high resolution spectra, low temperature and measurements of lifetime. Hydridic host materials will be from various classes of mainly ionic mixed anionic metal hydrides, e. g. perovskite-type hydride fluorides KCaH3-xFx (1 < x < 3), pyrochlore-type hydride fluorides and hydride oxides NaCaMg2F7-xHx, NaSrMg2F7-xHx, KCaNb2O6F1-xHx, and KCaTa2O6F1-xHx, hydride halogenides MHX (M = Ca, Sr, Ba; X = Cl, Br, I), lanthanide hydride oxides LnHO, and hydride silicates. Identifying and quantifying the crystal chemical key parameters for Eu(II) luminescence in such compounds will enable us to make predictions for the ideal chemical environment around europium atoms for a chosen emission wavelength, to suggest suitable crystal structures and thus the knowledge-driven development of luminescence materials. This will provide a deep understanding of Eu(II) luminescence in mixed-anionic metal hydrides at a level, where it can be used as a guide for the search of new luminescence materials.