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Aqueous zinc‐ion batteries (ZIBs) are promising for next‐generation energy storage. However, the reported electrode materials for ZIBs are facing shortcomings including low capacity and unsatisfactory cycling stability etc. Herein, hexaazatrinaphthalene‐quione (HATNQ) is reported for aqueous ZIBs. The HATNQ electrodes delivered an ultrahigh capacity (482.5 mAh g−1 at 0.2 A g−1) and outstanding cyclability of >10 000 cycles at 5 A g−1. The capacity sets a new record for organic cathodes in aqueous ZIBs. The high performances are ascribed to the rich C=O and C=N groups that endowed HATNQ with a 2D layered supramolecular structure by multiple hydrogen bonds in plane with π–π interactions out‐of‐plane, leading to enhanced charge transfer, insolubility, and rapid ion transport for fast‐charge and ‐discharge batteries. Moreover, the 2D supramolecular structure boosted the storage of Zn2+/H+, particularly the storage of Zn2+, due to the more favorable O⋅⋅⋅Zn⋅⋅⋅N coordination in HATNQ. [ABSTRACT FROM AUTHOR]

The oxidation of π–d‐conjugated coordination polymers (CCPs) accompanied with anion insertion has the merits of increasing the capacity and elevating the discharge voltages. However, previous reports on this mechanism either required more investigations or showed low capacity and poor cyclablity. Herein, triphenylene‐catecholate‐based two‐dimensional CCPs are constructed by employing inactive transition‐metal ions (Zn2+) as nodes, forming Zn‐HHTP. Substantial characterizations and theoretical calculations indicate the successive storage of cations and anions by redox reactions of only ligands, leading to a high reversible capacity of ≈150 mAh g−1 at 100 mA g−1 and a remarkable capacity retention of 90 % after 1000 cycles. On the contrary, as a control experiment, the analogous CCPs (Cu‐HHTP) with Cu2+ nodes, where both ligands and metal ions undergo redox reactions, accompanied by the storage of only Na+ cations, show a much poorer cyclability. These results highlight the importance of redox reactions of only ligands for long‐term cycle life and the insight into the storage mechanisms deepens our understanding on CCPs for the further design of CCPs with high performance. [ABSTRACT FROM AUTHOR]