Department of Chemistry, Oregon State University, Corvallis, Oregon, 97331-4003, USA.
Angew Chem Int Ed Engl. 2016 Oct 17;55(43):13480-13484. doi: 10.1002/anie.201607151. Epub 2016 Sep 27.
Uranyl polyoxometalate clusters are both fundamentally fascinating and potentially relevant to nuclear energy applications. With only ten years of development, there is still much to be discovered about heterometal derivatives and aqueous speciation and behavior. Herein, we show that it is possible to encapsulate the polyoxocations [Bi O ] and [Pb O ] in [(UO )(O )(OH)] (denoted Bi@U and Pb@U ) in pure form and high yields despite the fact that under aqueous conditions, these compounds are stable on opposite ends of the pH scale. Moreover, [Pb O ] is a formerly unknown Pb polynuclear species, both in solution and in the solid state. Raman spectroscopic and mass spectrometric analysis of the reaction solutions revealed the very rapid assembly of the nested clusters, driven by bismuth- or lead-promoted decomposition of excess peroxide, which inhibits U formation. Experimental and simulated small-angle X-ray scattering data of Bi@U and Pb@U solutions revealed that this technique is very sensitive not only to the size and shape of the clusters, but also to the encapsulated species.
铀多金属氧酸盐簇合物不仅在基础研究中具有重要意义，而且在核能应用方面也具有潜在的应用价值。尽管只有十年的发展历史，但对于杂多金属衍生物以及水相的形态和行为，仍有许多有待发现之处。在此，我们展示了尽管在水溶液条件下，这些化合物在 pH 值的两个极端都很稳定，但仍有可能以纯态和高产率将多阳离子 [Bi O ] 和 [Pb O ] 封装在 [(UO )(O )(OH)] 中（分别表示为 Bi@U 和 Pb@U ）。此外，[Pb O ] 是一种以前未知的 Pb 多核物种，无论是在溶液中还是在固态中都是如此。反应溶液的拉曼光谱和质谱分析表明，在过氧化物过量的情况下，铋或铅促进其分解，从而抑制了 U 的形成，促使嵌套簇的快速组装。Bi@U 和 Pb@U 溶液的实验和模拟小角 X 射线散射数据表明，该技术不仅对簇合物的大小和形状非常敏感，而且对封装的物种也非常敏感。
