轮状的多氧化物状态[Cu20Cl(OH) 24(H2O) 12(P8W48O184) ]25-宏离子在水溶液中形成超分子"黑"结构
Guang Liu1, Tianbo Liu, Sib Sankar Mal
1Department of Chemistry, Lehigh University, Bethlehem, Pennsylvania 18015, USA.
Journal of the American Chemical Society
|August 3, 2006
概括
研究人员发现,水友多氧化物自组合成空洞的球形"黑"型结构. 这一发现表明,对于宏离子来说,这是一个普遍的现象,而不是特定于多氧聚的现象.
科学领域:
- 无机化学 无机化学 有机化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 聚氧甲酸盐 (POMs) 是多功能无机集群,具有多样化的结构和特性.
- 宏的自我组装成复杂的结构是超分子化学的一个关键领域.
- 之前关于黑形成的研究仅限于多氧合物更新.
研究的目的:
- 为了研究一种新型的水友多氧化态的自我组装行为, [Cu20Cl(OH) 24(H2O) 12(P8W48O184) ]25- ({Cu20P8W48}).
- 为了探索黑类型结构的形成,使用这种不含的聚氧甲.
- 为了研究这些自我组装的宏观离子结构的电泳性质.
主要方法:
- 动态光散射 (DLS) 是一种
- 静态光散射 (SLS) 是一种
- 泽塔潜力分析
- 扫描电子显微镜 (SEM) 的使用
主要成果:
- 在水溶液中,{Cu20P8W48} 多氧化物状态自组装成单层,空洞,球形的黑结构.
- 这是第一份关于非含的聚氧甲酸形成黑的报告.
- 黑的形成独立于宏离子度和温度.
- {Cu20P8W48} 宏离子是迄今为止观察到的最小的表现出这种自我组装行为 (相当半径<2 nm).
- 电泳学研究表明,黑结构中的电荷密度低于自由宏离子,这表明与反离子有关.
结论:
- 黑类型的结构形成可能是极性溶剂中水友性宏离子的一般现象.
- {Cu20P8W48} 系统提供了关于稀释溶液中从简单离子过渡到宏离子的见解.
- 单价子 counterions 在宏子的自我组装中起着至关重要的作用,可能会调解黑形成的吸引力.
相关概念视频
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