LAUSR

Developing a facile strategy for the construction of vinylene-linked fully π -conjugated covalent organic frameworks (COFs) remains a huge challenge. Here, a versatile condition of Knoevenagel polycondensation for constructing vinylene-linked 2D COFs was explored. Three new examples of vinylene-linked 2D COFs ( BTH-1 , 2 , 3 ) containing benzobisthiazoles units as functional groups were successfully prepared under this versatile and mild condition. The electron-deficient benzobisthiazole units and cyano-vinylene linkages were both integrated into the π conjugated COFs skeleton and acted as acceptor moieties. Interestingly, we found the construction of a highly ordered and conjugated D-A system is favorable for photocatalytic activity. BTH-3 with benzotrithiophene as the donor with a strong D-A effect exhibited an attractive photocatalytic HER of 15.1 mmol h −1 g −1 under visible light irradiation. Synthesis of fully π -conjugated covalent organic frameworks (COFs) remains still challenging. Here, the authors propose a versatile synthesis method based on Knoevenagel polycondensation for the synthesis of vinylene-linked benzobisthiazole-based 2D COFs.