离子对银的超分子结构的影响:结构特征和吸性质
Irene Bassanetti1, Francesco Mezzadri, Angiolina Comotti
1Dipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica, Università degli Studi di Parma, Italy.
Journal of the American Chemical Society
|May 24, 2012
概括
这项研究详细介绍了从银和特定的连接物中制造出稳定,多孔的金属有机框架. 这些结构形成循环六合体,自组装成具有可调节的气体吸收孔径的3D架构.
科学领域:
- 超分子化学 超分子化学
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
背景情况:
- 预先组织的带提供受控的自我组装途径.
- 银(I) 离子是构建复杂超分子架构的多功能节点.
- 层次的自我组装是设计功能性多孔材料的关键.
研究的目的:
- 为了合成和描述新的超分子结构,使用乙烯功能化 bis ((pyrazolyl) 甲联体和银前体.
- 研究这些结构的等级组织,从离散的循环六元体到3D框架.
- 探索由此产生的金属有机框架的多孔性和气体吸附性质.
主要方法:
- 连接物 (L) 和银前体之间的复合反应.
- 用X射线衍射 (单晶和粉末) 进行结构确定.
- 气体吸附分析 (CO2,CH4,蒸汽吸附) 来评估孔隙性.
主要成果:
- 在溶液中形成稳定的,铁状金属有机循环六合体 ([AgL]6(X) 6).
- 在3D晶体架构中分层自组,不同的空间组 (Fd3,R3) 取决于对抗离子 (PF6-, BF4-, CF3SO3-, NO3-).
- 带有柏拉图式固体形状腔体的多孔框架的生成,在溶剂疏散时表现出永久的多孔性和可逆的气/蒸气吸收.
结论:
- 设计的连接体使得银能够形成强大的,分层组织的超分子结构.
- 阴离子决定了由此产生的3D框架的对称性和维度.
- 这些金属有机框架显示出作为二氧化碳和CH4等气体的选择性吸附剂的潜力.
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