Three-Dimensional Large-Pore Covalent Organic Framework with stp Topology

Abstract

Three-dimensional (3D) covalent organic frameworks (COFs) are excellent crystalline porous polymers for numerous potential appli-cations, but their building units and topological nets have been lim-ited. Herein we report the design and synthesis of the first 3D large-pore COF with stp topology constructed from a 6-connected triptycene-based monomer. The new COF (termed JUC-564) has a high specific surface area (up to 3300 m2 g-1), the largest pore (43 Å) among 3D COFs, and record-breaking low density (0.108 g cm-3) in crystalline materials to date. The large pore size of JUC-564 is confirmed by the incorporation of a protein. This study expands the structural varieties of 3D COFs based on the deliberate symmetry-guided design principle as well as their applications for adsorption and separation of large biological molecules.