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可见光光催化剂的捐赠-接受器 [2]

Yang Jiao¹, Luka Đorđević^1,2, Haochuan Mao^1,3

¹Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.

Journal of the American Chemical Society

|May 24, 2021

概括

机械增强的电荷转移复合物在 [2] 链中利用可见光进行光催化. 这一突破可以在没有外部光敏感剂的情况下实现高效的光降解和氧化, 展示太阳能和分子机器的潜力.

科学领域:

超分子化学
光催化
材料科学

背景情况:

在富含电子的捐赠体和缺乏电子的接受体之间形成电荷转移复合体 (CTC),缩小可见光吸收的HOMO-LUMO间隙.
CTC中的弱相互作用限制了它们在可见光光催化中的应用,需要更强大,更稳固的系统.

研究的目的:

通过在捐赠-接受 [2] 中使用机械结合来增强电荷转移相互作用.
研究可见光应用中机械增强的CTC的光催化活性.

主要方法:

通过循环和1,5-dinaphtho[38]crown-10的机械互锁合成一个捐赠-接受 [2]catenane.
由于机械粘合而增加可见光吸收的评估.
在生产和有氧氧化反应中证明光催化活性.

主要成果:

由于增强的电荷转移相互作用, [2]catenane 呈现出增强的可见光吸收.
在没有额外的光敏感剂的情况下,在可见光照射下产生了持久的双基离子.
在纳米粒子辅助的生产和有机硫化物的有氧氧化过程中,具有催化活性.

结论:

在机械上相互关联的分子中纳米封锁可以显著加强像电荷转移这样的弱相互作用.
这种方法扩大了CTC的太阳能转化和合成光催化潜力.
这些发现为开发先进的分子机器和设备开辟了新的途径.

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