Boosting Lithium Storage Performance of Small‐Molecule Organic Cathodes through Synergistic Molecular Engineering and Nanostructure Design

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Small‐molecule organic carbonyl compounds (SMOCCs) featuring high theoretical capacities are promising cathodes for lithium‐ion batteries (LIBs), but facing challenges in cycling stability and rate performance owing to their high solubility in organic electrolytes and low conductivity. Herein, we propose a novel architecture wherein nanosized SMOCCs with N‐heterocycle‐extended π‐conjugation are uniformly immobilized on reduced graphene oxide (rGO). This approach leverages the N‐heterocycles to create additional active sites and strengthen π‐π interactions with rGO, while the homogeneous distribution of nanosized SMOCCs on rGO facilitates efficient charge transport and electrolyte infiltration. As a demonstration, we synthesize a composite material using dipyrido[3’,2’:5,6;2′′,3′′:7,8]quinoxalino[2,3‐i]dipyrido[3,2‐a:2’,3’‐c] phenazine‐10,21‐dione (DQDPD) as the active component, which exhibits remarkable electrochemical properties in LIBs, including an ultrahigh capacity of 505 mAh g −1 at 0.2 A g −1 , exceptional cycle stability with 82 % capacity retention after 3000 cycles at 5 A g −1 , and outstanding rate capability of 290 mAh g −1 at 10 A g −1 . Our approach, which integrates molecular engineering and nanostructure design, provides a novel paradigm for simultaneously realizing high capacity, long lifespan, and rapid rate capability in SMOCCs.