Unprecedented Flux-Mediated Synthesis of Crystalline Polyimide Covalent Organic Frameworks Using the 4-Dimethylaminopyridine (DMAP)-Type Nucleophilic Catalyst for Use in Efficient Photosynthesis of H 2 O 2

作者：Minghui Chen, Junchen Wang, Tao Wei, Boxin Zhang, Boxin Zhang, Kai Guo, Yaqing Feng, Bao Zhang, Bao Zhang · 发表于：Journal of the American Chemical Society · 年份：2025 · DOI：10.1021/jacs.5c07684 · 被引用次数：40 · 研究领域：Covalent Organic Framework Applications、Metal-Organic Frameworks: Synthesis and Applications、Advanced Photocatalysis Techniques

Photocatalytic H 2 O 2 production from water and O 2 represents a sustainable approach for clean chemical synthesis, but developing efficient and stable photocatalysts remains challenging. Herein, we report a novel 4-dimethylaminopyridine (DMAP)-type nucleophilic catalyst-mediated flux synthesis strategy to prepare crystalline polyimide covalent organic frameworks (PI-COFs) as efficient photocatalysts for H 2 O 2 generation. Interestingly, by introducing molten DMAP as the reaction medium, we achieved three PI-COFs (DMAP-BNCOFs, DMAP-BBCOFs, and DMAP-NNCOFs) with significantly enhanced crystallinity and porosity compared to those obtained in conventional solvothermal synthesis. The optimized PI-COFs showed excellent photocatalytic activity, among which DMAP-BNCOFs could achieve a H 2 O 2 production rate of 8051.4 μmol h –1 g –1 without the presence of any sacrificial agents under visible-light irradiation, representing the most efficient polymeric/framework photocatalysts ever reported. The photocatalyst demonstrated remarkable stability over 90 h of continuous operation with no activity loss. DMAP-BNCOFs exhibited a lower exciton binding energy and longer excited-state lifetime compared with those of DMAP-BBCOFs and DMAP-NNCOFs. Experimental and theoretical studies revealed that enhanced performance stems from the optimal electronic structure, efficient charge separation, and accelerated O 2 activation. This work provides new insights into the flux synthesis approach and rat...