超四面体硫化物晶体具有巨大的腔和通道
1Supramolecular Design and Discovery Group, Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85287, USA.
Science (New York, N.Y.)
|February 19, 1999
概括
研究人员使用超四面体集群开发了新的多孔硫化框架 (ASU-31和ASU-32). 这些材料呈现出大腔和通道,并允许离子交换而不会造成结构损伤.
科学领域:
- 材料科学 材料科学 材料科学
- 无机化学 无机化学
- 晶体工程公司 晶体工程
背景情况:
- 基酸盐和金属酸盐很容易形成多孔的开放框架材料,如天岩.
- 硫化物类似物通常会产生高密度相,这是由于硫的四面角很小.
- 开发多孔硫化物材料需要创新的策略来克服结构限制.
研究的目的:
- 为了合成和描述新硫化开放框架材料.
- 研究使用超四面体集群作为多孔硫化物网络的构建块.
- 探索这些新材料的结构性质和客人交流能力.
主要方法:
- 印度硫化物化合物的热水合成.
- 单晶X射线衍射用于结晶结构的确定.
- 用水溶液中的离子进行客人交换实验.
主要成果:
- 两个新的硫化开放框架,ASU-31和ASU-32,已成功准备好.
- ASU-31具有大腔 (25.6 Å直径) 的 sodalite-tetrahedrite 拓结构.
- ASU-32 呈现出具有显著通道 (≥14.7 Å 直径) 的四角形 CrB4 型网络.
- 两个框架中的有机模板离子在室温下完全与离子交换,而没有晶体降解.
结论:
- 超四面体集群是创建基于多孔硫化物的开放框架的有效基石.
- 合成的硫化框架 (ASU-31和ASU-32) 具有适合潜在应用的大孔尺寸.
- 证明的离子交换能力凸显了这些材料在分离或催化等领域的潜在用途.
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