Perylene-Based 2D Covalent Organic Frameworks for Selective Adsorption and Extraction of C60

The structures and functions of covalent organic frameworks (COFs) can be precisely tuned via manipulation of reticular chemistry. COFs have been widely utilized as a multifunctional porous material owing to their uniform pore size, designable pore environment, and high surface area. In this work, a series of two-dimensional (2D) perylene-based microporous COFs, named TFPP-TAPP-COF, TFPP-TAPE-COF, and TFPP-CoTPAP-COF, were developed based on the C4 + C4 topological diagram. These COFs exhibit excellent crystallinity, high surface area, and strong robustness against various organic solvents, moisture, and strong acid and base aqueous solutions. Owing to the electron-donating nature of perylene units, these COFs can have strong host–guest interaction with the electron-accepting fullerenes. It is noteworthy that all three perylene-based COFs exhibited exceptional capacity and high efficiency for fullerene capture. In addition, TFPP-TAPE-COF has a higher adsorption selectivity of C60 over C70 due to its appropriate pore size, which allows selective extraction of C60 from C60 and C70 mixtures. These results illustrate that these perylene-based 2D COFs can serve as a powerful custom-built platform for the enrichment, extraction, and separation of fullerenes.