Following the Reactivity of Au25(SC8H9)18鈥?/sup> Clusters with Pd2+ and Ag+ Ions Using in Situ X-ray Absorption Spectrosco

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• 作者：Atal Shivhare ; Kee Eun Lee ; Yongfeng Hu ; Robert W. J. Scott
• 刊名：Journal of Physical Chemistry C
• 出版年：2015
• 出版时间：October 8, 2015
• 年：2015
• 卷：119
• 期：40
• 页码：23279-23284
• 全文大小：363K
• ISSN：1932-7455

文摘

This work examines the reaction between Au₂₅(SC₈H₉)₁₈^{鈥?/sup> clusters with palladium acetate (Pd2+) and silver nitrate (Ag+) using UV鈥搗is, transmission electron microscopy (TEM), extended X-ray absorption spectroscopy (EXAFS), and in situ liquid cell X-ray absorption spectroscopy (XAS). UV鈥搗is results show that upon the addition of Pd2+ and Ag+ salts to Au₂₅(SC₈H₉)₁₈鈥?/sup> clusters significant changes are seen in the optical properties of the clusters. In the case of Pd, there is little to no change in the size of the clusters evidenced by TEM, while for Ag systems, significant particle growth is seen. In situ XAS results show that Pd2+ reacts with the staple motifs of Au₂₅(SC₈H₉)₁₈鈥?/sup> clusters and forms Pd(II) thiolate species, as shown by the Pd L₃- and Au L₃-edge data as well as Pd K-edge EXAFS results. However, Ag L₃-edge data suggest that Ag+ reduces to Ag on the cluster core and does not form Ag(I) thiolate species. This work highlights the power of using in situ XANES to follow Au cluster transformations in liquid environments.}