Giant Ln30-Cluster-Embedded Polyoxotungstate Nanoclusters with Exceptional Proton-Conducting and Luminescent Properties

Although the synthesis of giant lanthanide (Ln)containing polyoxotungstates (POTs) has long been actively pursued, it remains challenging to encapsulate high-nuclearity Ln-O clusters in POT shells because of the highly complicated assembly process. This work demonstrates a simple synthetic strategy of using lacunary POT precursors to assemble with in situ generated Ln-O clusters in the presence of basic N-containing ligands, which exert a slow-releasing effect for Ln(3+) ions in alkaline conditions. With this strategy, two giant Ln(30)-cluster-embedded polyoxometalates (POMs) H38Na10K14(TMEDA)(8)[Ln(30)Ge(12)W(107)O(420) (OH)(2)(H2O)(14)]center dot solvents (1Ln) (Ln = Sm, Eu) have been successfully synthesized, which not only represent two rare high-nuclearity POM macromolecules with over 100 W atoms but also a unique Ge2W7. Ln30. W100 multishell configuration. The incorporated Ln-O clusters in [Ln(30)Ge(12)W(107)O(420) (OH)(2)(H2O)(14)](62-) (Ln(30)W(107)) with a nuclearity of 30 are larger than any known Ln-clusters observed in POM chemistry. Additionally, they contain the largest number of Sm and Eu centers for any POMs reported to date. Interestingly, the unique structural features and the high-nuclearity Ln-O clusters endow Ln(30) W-107 with excellent proton conductivities over a wide temperature range and unusual luminescence properties.

Automated summary

A simple synthetic strategy using lacunary POT precursors and N-containing ligands has been demonstrated to successfully synthesize giant Ln(30)-cluster-embedded POMs, which exhibit unique high-nuclearity structures and excellent proton conductivity and luminescence properties.