Composition-defined nanosized assemblies that contain heterometallic early 4d/5d-transition-metals
Composition-defined nanosized assemblies that contain heterometallic early 4d/5d-transition-metals
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DOI：
10.1039/c9dt03094h
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发表时间：
2019-10-14
影响因子：
4
通讯作者：
Yamamoto，Kimihisa
中科院分区：
文献类型：
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作者：
Wakizaka，Masanori;Imaoka，Takane;Yamamoto，Kimihisa
早期过渡金属的可控组装仍然是一个具有挑战性的研究目标，特别是在生成异金属分子和纳米材料方面。在这项研究中，早期4d/5d过渡金属的金属氯化物，即，ZrCl 4，NbCl 5，MoCl 5，HfCl 4，TaCl 5，和WCl 6，在最佳量的有机配体如吡啶和3-氯吡啶的存在下化学计量地引入到四苯基甲烷核树枝状-苯基偶氮甲碱第4代树枝状聚合物中。树枝状大分子中的金属氯化物和亚胺之间的配位相互作用表明金属的刘易斯酸性呈正相关。此外，它是第一次清楚地表明，异金属组件的定义组成包含四种早期的4d/5d过渡金属，如TaV，NbV，MoV，和ZrIV，这是证实了紫外-可见滴定，XPS，HAADF-STEM/EDS测量。这项研究的结果应该提供新的途径来生产由异金属早期4d/5d过渡金属组成的纳米材料。
The controlled assembly of early transition metals remains a challenging research target, especially with respect to the generation of heterometallic molecules and nanomaterials. In this study, metal chlorides of the early 4d/5d-transition-metals, i.e., ZrCl4, NbCl5, MoCl5, HfCl4, TaCl5, and WCl6, were stoichiometrically introduced into a tetraphenylmethane-core dendritic-phenylazomethine generation 4 dendrimer in the presence of an optimal amount of organic ligands such as pyridine and 3-chloropyridine. The coordinative interactions between the metal chlorides and the imines in the dendrimers indicated a positive correlation for the Lewis acidity of the metals. Moreover, it was clearly demonstrated for the first time that heterometallic assemblies of defined composition contain four kinds of early 4d/5d-transition-metals, such as TaV, NbV, MoV, and ZrIV, which was confirmed by UV-vis titration, XPS, and HAADF-STEM/EDS measurements. The results of this study should provide access to new routes to produce nanomaterials composed of heterometallic early 4d/5d-transition metals.