日本东京大学Kosuke Suzuki研究团队合成并表征了一类在金属氧化物分子空腔里的表面暴露的银纳米团簇。相关论文发表在2023年6月8日出版的《自然—化学》杂志上。

该研究组报道了在环形分子金属氧化物（杂多酸）的空腔中结构清晰的{Ag30}纳米团簇的连续合成。{Ag30}纳米团簇拥有暴露银表面，但在溶液和固态中被周围环形的杂多酸物种稳定化。这些团簇可在没有不良集聚或分解情况下完成还原诱导的结构转变。

此外，{Ag30}纳米团簇显示出高催化活性，可在温和的反应条件下用氢气对几类有机官能团选择性还原。课题组认为，这些发现可用于独立合成被分子金属氧化物稳定化的表面暴露的金属纳米团簇，其在诸如催化和能量转化中可能找到应用。

据悉，金属纳米团簇的表面，包括其与金属氧化物的界面，具有高反应活性，在催化应用中是有吸引力的。然而，这种高反应活性也阻碍了结构清晰的、具有暴露表面或界面的金属纳米团簇和金属氧化物的合成研究。

附：英文原文

Title: Surface-exposed silver nanoclusters inside molecular metal oxide cavities

Author: Yonesato, Kentaro, Yanai, Daiki, Yamazoe, Seiji, Yokogawa, Daisuke, Kikuchi, Takashi, Yamaguchi, Kazuya, Suzuki, Kosuke

Issue&Volume: 2023-06-08

Abstract: The surfaces of metal nanoclusters, including their interface with metal oxides, exhibit a high reactivity that is attractive for practical purposes. This high reactivity, however, has also hindered the synthesis of structurally well-defined hybrids of metal nanoclusters and metal oxides with exposed surfaces and/or interfaces. Here we report the sequential synthesis of structurally well-defined {Ag30} nanoclusters in the cavity of ring-shaped molecular metal oxides known as polyoxometalates. The {Ag30} nanoclusters possess exposed silver surfaces yet are stabilized both in solution and the solid state by the surrounding ring-shaped polyoxometalate species. The clusters underwent a redox-induced structural transformation without undesirable agglomeration or decomposition. Furthermore, {Ag30} nanoclusters showed high catalytic activity for the selective reduction of several organic functional groups using H2 under mild reaction conditions. We believe that these findings will serve for the discrete synthesis of surface-exposed metal nanoclusters stabilized by molecular metal oxides, which may in turn find applications in, for example, the fields of catalysis and energy conversion.

DOI: 10.1038/s41557-023-01234-w

Source: https://www.nature.com/articles/s41557-023-01234-w