Phosphorescence in Mn 4+ -Doped R + / R 2+ Germanates ( R + = Na + or K + , R 2+ = Sr 2+ )
Phosphorescence in Mn 4+ -Doped R + / R 2+ Germanates ( R + = Na + or K + , R 2+ = Sr 2+ )
复制标题
Mn 4 掺杂的 R / R 2 锗酸盐（R = Na 或 K，R 2 = Sr 2 ）中的磷光
DOI：
10.1021/acs.inorgchem.2c01364
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发表时间：
2022
影响因子：
4.6
通讯作者：
Mozharivskyj, Yurij
中科院分区：
文献类型：
--
作者：
Novikov, Sergei A.;Lu, Yimin;Zhang, Weiguo;Halasyamani, P. Shiv;Hariyani, Shruti;Brgoch, Jakoah;Klepov, Vladislav V.;zur Loye, Hans-Conrad;Mozharivskyj, Yurij
合成了三个新化合物：Na0.36Sr0.82Ge4O9(1)、Na2SrGe6O14(2)和K2SrGe8O18(3)，并用X射线单晶衍射仪对其进行了表征。它们的结构包含由GeO4和GeO6多面体构建的三维(3D)阴离子骨架。Ge4+八面体晶位的存在使新相适合于Mn4+取代得到红色发光材料，具有潜在的光转换应用前景。研究了Mn4+取代的Na2SrGe6O14(2)和K2SrGe8O18(3)样品在一定温度范围内的光致发光性质，观察到了与四价锰的电子跃迁相关的红光发光。在类似于先前研究的Na2CaGe6O14：Pr3+的混合Na-Sr位上，Na2SrGe6O14(2)相也被Pr3+取代。与Mn4+激活剂相比，Pr3+激活剂的红光发射峰位于更短的波长(610 Nm)(662-663 nm)。此外，还收集了非中心对称的Na2SrGe6O14(2)相的二次谐波产生(SHG)数据，表明二次谐波活性很弱。用漫反射光谱和态密度计算估算了原始Na2SrGe6O14(2)和K2SrGe8O18(3)相的带隙。
Single crystals of three new compounds, Na0.36Sr0.82Ge4O9(1, proposed composition), Na2SrGe6O14(2), and K2SrGe8O18(3), were obtained and characterized using single-crystal X-ray diffraction. Their structures contain three-dimensional (3D) anionic frameworks built from GeO4and GeO6polyhedra. The presence of octahedral Ge4+sites makes the new phases suitable for Mn4+substitution to obtain red-emitting phosphors with a potential application for light conversion. Photoluminescence properties of Mn4+-substituted Na2SrGe6O14(2) and K2SrGe8O18(3) samples were studied over a range of temperatures, and red light photoluminescence associated with the electronic transitions of tetravalent manganese was observed. The Na2SrGe6O14(2) phase was also substituted with Pr3+on the mixed Na–Sr site similar to the previously studied Na2CaGe6O14:Pr3+. The red emission peak of the Pr3+activator occurs at a shorter wavelength (610 nm) compared to that of Mn4+(662–663 nm). Additionally, second harmonic generation (SHG) data were collected for the noncentrosymmetric Na2SrGe6O14(2) phase, indicating weak SHG activity. Diffuse reflectance spectroscopy and density of states calculations were performed to estimate the band gap values for pristine Na2SrGe6O14(2) and K2SrGe8O18(3) phases.