Synthesis of highly crystalline imine-linked covalent organic frameworksviacontrolling monomer feeding rates in an open system

Covalent organic frameworks (COFs) have enormous potential in various applications because of their high crystallinity and superior surface area. However, it is still challenging to synthesize crystalline COFs using a convenient and effective synthetic strategy. Herein, we report a strategy to synthesize four highly crystalline imine COFs, namely, TATB-DATP-COF, PDA-TAPB-COF, OMePDA-TAPB-COF and COF-320, by polymerization with a dropwise monomer feeding method in an open system, without using additional templates or modulators. By controlling the feeding rates of the monomer, the reversibility of imine formation, defect self-healing and error correction can be improved.