Binding alkali metal ions in solutions is an important yet difficult task and it is especially true for a solid host in aqueous systems. This study shows that a water stable, anionic metal–organic framework (Zr-dobdc) is capable of capturing M⁺ (M = Li, Na, K, Rb, and Cs) ions dissolved in water through ion exchange. The alkali metal ions captured at the unique cation-binding pockets of Zr-dobdc and their ordered alignments in the crystal lattice are unambiguously characterized by X-ray single-crystal and powder diffraction studies. The apparent selectivity for alkali metal ions over other metal ions is also explained.

中文翻译：

---

阴离子Zr金属-有机骨架孔中有序碱金属离子的合成后离子交换及表征

在溶液中结合碱金属离子是一项重要但困难的任务，对于水性体系中的固体主体尤其如此。该研究表明，水稳定的阴离子金属-有机骨架 ( Zr-dobdc ) 能够通过离子交换捕获溶解在水中的M ⁺（M = Li、Na、K、Rb 和 Cs）离子。在Zr-dobdc的独特阳离子结合口袋中捕获的碱金属离子及其在晶格中的有序排列通过 X 射线单晶和粉末衍射研究明确表征。还解释了碱金属离子相对于其他金属离子的表观选择性。