Guest-Induced Self-Adaptive Pore Dynamic Behaviour of 2D Covalent Organic Frameworks

Abstract

Two-dimensional (2D) covalent organic frameworks (COFs) are typically regarded as having rigid in-plane pores. In this study, we successfully synthesized a series of 2D COFs (NUS 126-128) characterized by a staggered AB stacking arrangement throughout the network. These 2D COFs exhibit a reversible dynamic behavior of their in-plane pores in the presence of guest molecules, displaying pore breathing behavior with a reversible switch between large pores (lp) and narrow pores (np). This pore-breathing behaviour is ascribed to the interaction between COFs and solvent molecules.