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Redox-active covalent organic frameworks (COFs) are a new class of material with the potential to transform electrochemical energy storage due to the well-defined porosity and readily accessible redox-active sites of COFs. However, combining both high specific capacity and energy density in COF-based batteries remains a considerable challenge. Herein, we demonstrate the exceptional performance of Aza-COF in rechargeable sodium-ion batteries (SIBs). Aza-COF is a microporous 2D COF synthesized from hexaketocyclohexane and 1,2,4,5-benzenetetramine by a condensation reaction, which affords phenazine-decorated channels and a theoretical specific capacity of 603 mA h g^–1. The Aza-COF-based electrode exhibits an exceptional average specific capacity (550 mA h g^–1), energy density (492 W h kg^–1) at 0.1 C, and power density (1182 W kg^–1) at 40 C. The high capacity and energy density are …