坚固的共价有机框架光催化剂用于H2O2生产:链接位置很重要
Tao Yang1, De Zhang2, Aiguo Kong1
1School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, 200241, P. R. China.
Angewandte Chemie (International ed. in English)
|March 17, 2024
概括
设计强大的共价有机框架 (COF) 是高效光催化过氧化 (H2O2) 合成的关键. 与平行链接的COF相比,形链接的COF表现出优越的稳定性和活性,为人工H2O生产提供了一个有前途的战略.
科学领域:
- 材料科学 材料科学 材料科学
- 光催化作用的光催化
- 绿色化学 绿色化学
背景情况:
- 共价有机框架 (COF) 是具有光催化潜力的先进材料.
- 在COF光催化剂中实现高活性和稳定性之间的平衡,以合成过氧化 (H2O2),仍然是一个挑战.
- 现有的方法通常需要牺牲试剂,限制实际应用.
研究的目的:
- 为了研究链接异构体 (ortho-vs. para-) 对COF光催化剂用于H2O2合成的性能的影响.
- 开发强大的COF光催化剂,具有高活性和稳定性,无需牺牲试剂.
- 阐明COF设计中的结构-活动关系和稳定机制.
主要方法:
- 通过使用1,3,5-三甲基和各种二胺,合成正链 (o-COFs) 和链 (p-COFs).
- 对H2O2生产率的光催化评估和在纯水中进行长期稳定性测试.
- 密度函数理论 (DFT) 计算以调查反应机制,活性点和稳定性.
主要成果:
- 含有pyrzaine的o-COFs表现出高的H2O2生产率 (4396μmol g-1 h-1) 和持续的性能超过48小时.
- 与他们的p-COF对应物相比,o-COFs表现出更高的活性和稳定性.
- DFT计算澄清了反应机制,并确定了o-COF中增强稳定的来源.
结论:
- 链接异构体显著影响COFs在H2O2合成中的光催化性能和稳定性.
- 骨关联的COF,特别是那些含有酸的COF,为高效和持久的人工光合作用提供了一个有前途的平台.
- 本研究提出了一个简单的分子设计策略,用于创建先进的COF光催化剂.
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