2D Covalent Organic Frameworks with Kagome lattice: Synthesis and Applications

2D covalent organic frameworks with kagome (kgm) topology are a promising class of crystalline frameworks that possess both triangular micropores and hexagonal mesopores. These dual-pore structures enable kgm COFs to exhibit unique advantages in selective separation, mass transfer, and targeted drug release. However, the synthesis of 2D kgm COFs has been hindered by the reliance on empirical methods. In this review, we systematically summarize the conventional macrocycle-to-framework strategy, typical [4+2] co-polymerization synthetic strategy, and bifunctional molecules self-condensation approach for constructing 2D kgm COFs. We also survey the factors influencing formation of kgm lattice such as monomer type, solvent polarity, substrate concentration, etc., and highlight the representative examples on targeted synthesis. Additionally, we summarize the applications of 2D kgm COFs and the relationships between structure and performances. Finally, we propose key fundamental perspectives to accelerate the further development of this intriguing material.