Hierarchical porous covalent organic framework/graphene electrode for high-energy–density supercapacitors

This study presented a novel approach to enhance supercapacitor (SC) performance by integrating covalent organic framework (COF)–based electrodes. Anthracene-containing DaTp-COF was in situ grown on graphene (DaTp/rGO) via π-π interactions, addressing the poor conductivity of pure DaTp-COF. The composite exhibited a hierarchical porous structure, facilitating ion transport and high electron conductivity. The resulting DaTp/rGO shows a pseudocapacity induced by push–pull electronic flow of anthracene structures in 0.5 M H 2 SO 4 . When paired with an ionic liquid-derived ionogel electrolyte (offering a wide voltage window), the DaTp/rGO electrode achieved a specific capacitance of 183 F/g and an energy density of 58 Wh/kg at 75 W/kg. Comparative analysis with benzene and anthraquinone-based COFs (DbTp and DqTp) revealed that meso-macroporous structures in DaTp/rGO were critical for ionogel compatibility, enabling efficient double-layer capacitance. The fabricated solid-state SC retained 70% of its initial capacitance after 10,000 cycles, highlighting its durability. This work underscores the crucial role of unique pore structures in COF on the electrochemical properties of supercapacitors, paving the way for high-energy–density energy storage devices.