Han Chao-Qin, Guo Jia-Xin, Sun Shuai, Wang Ze-Yang, Wang Lei, Liu Xiao-Yuan
Hoffmann Institute of Advanced Materials, Shenzhen Polytechnic University, 7098 Liuxian Blvd, District Nanshan, Shenzhen, 518055, P. R. China.
Small. 2024 Dec;20(49):e2405887. doi: 10.1002/smll.202405887. Epub 2024 Sep 9.
Covalent organic frameworks (COFs) have emerged as one of the most studied photocatalysts owing to their adjustable structure and bandgaps. However, there is limited research on regulating the light-harvesting capabilities of acceptor building blocks in donor-acceptor (D-A) isomer COFs with different bond orientations. This investigation is crucial for elucidating the structure-property-performance relationship of COF photocatalysts. Herein, a series of D-A isostructural COFs are synthesized with different imine bond orientations using benzothiadiazole and its derivatives-based organic building units. Extended light absorption is achieved in COFs with acceptor groups that have strong electron-withdrawing capacities, although this resulted a decreased hydrogen generation efficiency. Photocatalytic experiments indicated that dialdehyde benzothiadiazole-based COFs, HIAM-0015, exhibit the highest hydrogen generation rate (17.99 mmol g h), which is 15 times higher than its isomer. The excellent photocatalytic performance of HIAM-0015 can be attributed to its fast charge separation and migration. This work provides insights into the rational design and synthesis of D-A COFs to achieve efficient photocatalytic activity.
共价有机框架（COFs）因其可调节的结构和带隙，已成为研究最多的光催化剂之一。然而，对于具有不同键取向的供体-受体（D-A）异构COFs中受体结构单元的光捕获能力调控研究有限。这项研究对于阐明COF光催化剂的结构-性质-性能关系至关重要。在此，使用基于苯并噻二唑及其衍生物的有机结构单元，合成了一系列具有不同亚胺键取向的D-A同构COFs。在具有强吸电子能力受体基团的COFs中实现了扩展光吸收，尽管这导致析氢效率降低。光催化实验表明，基于二醛苯并噻二唑的COF，HIAM-0015，表现出最高的析氢速率（17.99 mmol g h），比其异构体高15倍。HIAM-0015优异的光催化性能可归因于其快速的电荷分离和迁移。这项工作为合理设计和合成D-A COFs以实现高效光催化活性提供了见解。
