Carbazole-Based Imine-Linked Covalent Organic Framework for Efficient Heterogeneous Photocatalysis

Donor–acceptor covalent organic framework (COF) materials have proven to be an optimal choice for heterogeneous photocatalysis due to their capacity for effective charge separation and harvesting of visible light. The poor chemical and photostability of imine-linked D–A COFs restrict their potential for broader applications. So, researchers are focused on developing imine-linked COFs with enhanced photocatalytic activity. In this study, we also emphasize the pivotal role of molecular engineering to overcome these challenges. Herein, a carbazole-based highly crystalline D–A CzDA-TAPT COF was developed. Not only does the incorporation of the alkyl group-substituted carbazole provide excellent donor ability, but also the butyl groups in the pore skeleton guide the attachment of successive layers in different AB stackings, significantly amplifying the photocatalytic efficiency of the CzDA-TAPT COF by providing more active sites for the reaction. Compared with previously reported photoactive benzothiadiazole-based COFs, this innovative material exhibits superior charge separation and heightened photostability, resulting in a notable advancement in the photocatalytic aerobic oxidation of aryl boronic acids to phenols.