在单晶共价有机框架中的链接转换
Baoqiu Yu1, Rui-Biao Lin2, Gang Xu3
1Beijing Advanced Innovation Center for Materials Genome Engineering, Beijing Key Laboratory for Science and Application of Functional Molecular and Crystalline Materials, Department of Chemistry and Chemical Engineering, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, China.
Nature chemistry
|September 18, 2023
概括
研究人员开发了一种灵活的共价有机框架 (COF),具有相互透的qtz拓. 这种材料表现出独特的结构转变,并在酸加载后实现高质子导电性.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 聚合物化学 聚合物化学
背景情况:
- 单晶X射线衍射对于确定原子结构至关重要,但对共价有机框架 (COF) 具有挑战性,特别是那些经历了合成后修改的结构.
- 开发可保持单晶完整性的灵活COF对于先进的表征和功能应用至关重要.
研究的目的:
- 合成一种灵活的COF,具有适合单晶分析的相互透的qtz拓.
- 为了研究材料的灵活性,结构转变,以及对质子导电性的潜力.
主要方法:
- 通过聚合基于四甲和四胺的四甲和四胺构成块来合成柔性COF.
- 使用单晶X射线衍射进行表征,观察结构变化.
- 评估热膨胀和溶剂去除引起的变化.
- 评估氧化还原诱导的结合转换 (imine到amine/amide) 和质子导电性测量.
主要成果:
- 一个灵活的COF与相互透的qtz拓学成功合成.
- 该材料显示出显著的异性质正热膨胀 (αc = +491 × 10−6 K−1) 和在去除溶剂后的结构转变.
- 单晶到单晶的转换是通过氧化还原诱导的 imine 连接转换实现的.
- 酸加载导致无水质子导电率高达6.0 × 10−2 S cm−1.1.
结论:
- 合成的柔性COF可进行单晶分析,并具有可调节的结构性质.
- 氧化诱导的链接转换增强了材料的稳定性,并为诸如质子导电等功能应用打开了通路.
- 这项工作提出了一个有前途的策略,用于设计可靠和适应性强的COF,用于先进的材料应用.
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