在共价有机框架中结构结合调整可提高电荷转移和光催化性能
Qihan Lin1, Yusran Yusran1,2, Jiabin Xing1
1Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 2005 Songhu Road, Shanghai 200438, P. R. China.
ACS applied materials & interfaces
|January 26, 2024
概括
乙结合的共价有机框架 (AC-COFs) 呈现出增强的结合,导致更好的可见光吸收和电荷转移. 这使得AC-COF成为氨酸氧化和C-O交叉合反应的高效光催化剂.
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
- 有机化学 有机化学
背景情况:
- 共价有机框架 (COF) 的光学和电子特性受到它们的结构合的显著影响.
- 开发高效的COF光催化剂对于太阳能转化为化学能量的转化至关重要.
研究的目的:
- 为了研究二维二氧化中不同π-结合框架 (双与乙) 如何影响它们的光催化性能.
- 为设计先进的COF光催化剂建立结构-活动关系.
主要方法:
- 用二 (BPh-COF) 和乙 (AC-COF) 框架合成二维二氧化碳.
- 对COF的结晶性,多孔性和光学性质的表征.
- 电荷转移和光催化活动的计算和实验评估.
主要成果:
- 与BPh-COF相比,AC-COF表现出更广泛的可见光吸收和更窄的带隙,这是由于来自乙烯基骨架的 π 结合增强而导致的.
- AC-COF表现出高效的光诱导电荷分离和转移,从而在氨酸氧化合和金属光催化C-O交叉合反应中表现出卓越的性能.
- 在AC-COF中,它使得前所未有的二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二二
结论:
- 在AC-COF中的乙烯基骨架显著增强了π-结合,改善了电荷转移和光催化效率.
- 在太阳能驱动的化学合成中,AC-COF是一种有前途的材料,包括具有挑战性的C-O合反应.
- 这项工作为光催化提供了调整COF结构-活性关系的简单策略.
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