通过将素连接到共价有机框架的工程电荷转移,用于光催化牺牲的演化
Fangpei Ma1, Xiao Chi2, Ying Wen1
1State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University Nanjing 211816 China njutzhouyu@njtech.edu.cn junwang@njtech.edu.cn.
Chemical science
|June 18, 2025
概括
这项研究介绍了化共价有机框架 (COFs),以实现高效,无共催化剂的光催化进化. 含的COF在海水中表现出卓越的性能,克服了以前的限制.
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:
- 聚合有机框架 (COF) 显示了光催化演化反应 (HER) 的潜力.
- 现有的COF通常需要昂贵的联合催化剂,在海水中表现不佳.
- 优化海水条件下的COF属性对于实际应用至关重要.
研究的目的:
- 为了研究将素 (F,Cl,Br) 整合到COF中,以增强光催化进化的效果.
- 开发一种无共催化剂的HER系统,其活性得到改善,特别是在海水中.
- 阐明增强性能背后的机制.
主要方法:
- 化COF (TpPaCl, TpPaF, TpPaBr) 的合成.
- 在纯水和人工/真实海水中测量光催化演化速率.
- 理论计算 (DFT) 和软X射线吸收光谱 (XAS) 用于机械研究.
主要成果:
- 含的COF (TpPaCl) 实现了显著的无辅助催化剂HER率 (16.3 mmol g-1 h-1 在人造海水中).
- TpPaCl在纯水和其他化变体中表现优于COF,在海水中表现出优越的活性.
- 素的结合优化了电子特性,为进化创造了活跃点,并增强了电荷转移.
结论:
- 电子负原子,特别是,有效调整COF属性,以有效地 HER.
- 该研究提出了一个有前途的无共催化剂的COF系统,用于在具有挑战性的海水环境中生产气.
- 了解素诱导极化作用是设计先进光催化剂的关键.
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