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Covalent organic frameworks (COFs) possess intrinsic nanoscale pores, limiting mass transport and impacting their utility in many applications, such as catalysis, supercapacitors, and gas storage, demanding efficient diffusion throughout the material. Hierarchical porous structures, integrating larger macropores with inherent micro‐/meso‐pores, facilitate rapid mass transport. Recently, the fabrication of aerogel monoliths is reported exclusively from imine‐linked COFs, offering flexibility in aerogel composition. However, challenges in synthesizing robust β‐ketoenamine‐based COFs with comparable surface areas prompted innovative synthetic approaches. Leveraging the dynamic nature of COF bonds, in this work efficient monomer exchange from imine to partially β‐ketoenamine‐linked COFs within the gel phase is demonstrated. These aerogels can be transformed into electrodes using the compression technique. The new flexible electrodes‐based β‐ketoenamine‐linked COF composites with C super P exhibit superior durability and redox activity. Through supercapacitor assembly, the β‐ketoenamine‐linked COF electrodes outperform their imine‐based counterparts, showcasing enhanced capacitance (88 mF cm−2) and stability at high current densities (2.0 mA cm−2). These findings underscore the promise of β‐ketoenamine‐linked COFs for pseudocapacitor energy storage applications. [ABSTRACT FROM AUTHOR]

Redox-active covalent organic frameworks (COFs) are promising electrode materials for metal-ion batteries owing to their tunable electrochemical properties, adjustable structure, and resource availability. Herein, we report a series of two-dimensional tetrathiafulvalene (TTF)-based COFs incorporating different organic linkers between the electroactive moieties. These COFs were investigated as p-type organic cathode materials for lithium-organic batteries. The electrical conductivity of both neutral and doped TTF-COFs was measured using a van der Pauw setup, and their electronic structures were investigated through quantum-chemical calculations. Binder-free buckypaper TTF-based electrodes were prepared and systematically tested as organic cathodes in lithium half-cells. The results revealed high average discharge potentials (∼3.6 V vs. Li/Li+) and consistent cycling stability (80% capacity retention after 400 cycles at 2C) for the three TTF-COF electrodes. In addition, the specific capacity, rate capability, and kinetics varied depending on the structure of the framework. Our results highlight the potential of TTF-COFs as high-voltage organic cathodes for metal-ion batteries and emphasize the importance of molecular design in optimizing their electrochemical performance. [ABSTRACT FROM AUTHOR]