Morphological Modulation and Performance Tuning of Perylene-Porphyrin-Based Covalent Organic Frameworks

Large-scale production of covalent organic frameworks (COFs) has been hindered due to their poor reproducibility. Precisely controlling the growth of COFs can be achieved via alterations to synthesis parameters. A strategy for synthesizing reproducible perylene-porphyrin-based COFs over a range of temperatures is presented, with the aim to evaluate their morphology and functionality. Morphological modifications from nanospheres to nanofibers were observed at higher synthesis temperatures, which enhanced chemisorption in methylene blue removal experiments. Photoluminescence and transient absorption spectroscopy measurements showed efficient light absorption over the visible region and ultrafast excited-state deactivation, representative of a potential equilibrium with a charge-separated state, indicating the valuable photophysical behavior of our COFs.