Aqueous zinc-ion batteries (AZIBs) are being considered new choices of batteries not only because of their inherent safety but also because of their low price advantage. Nevertheless, it is still an important task to develop organic cathode materials with green sustainability and high performance. Hexaazatriphenylene (HAT)-based organic materials have shown great potential for use in AZIBs. Herein,5,6,11,12,17,18hexaazatrinaphthylene-2,8,14-tricarboxylic acid (HATTA) is designed and prepared as the AZIB cathode. Benefiting from the conjugative effect of −COOH, extended π-conjugated structure, and abundant active sites, the HATTA electrode exhibits a high capacity (225.8 mA h g −1 at 0.05 A g −1 ), an outstanding rate performance (136.1 mA h g −1 at 25 A g −1 ), and a long-term cycling lifespan (84.07% of the initial capacity after 10,000 cycles at 25 A g −1 ). Meanwhile, the characterization results of ex situ spectroscopic tests prove that the unsaturated bond (C�N) is the redox-active moiety of HATTA. In addition, the flexible Zn//HATTA battery also exhibits impressive long-term cycling stability and good flexibility, showing its promising application in wearable electronics. This work provides a strategy with rational designing for constructing high-performance AZIBs with organics.

The development of oxygen electrode reactions based on earth-abundant nonprecious materials is critically important for the substantial advancement of rechargeable Zn-air batteries (ZABs). Herein, a superb bifunctional electrocatalyst composed of...

Aqueous zinc-ion batteries (AZIBs) are deemed as an emerging substitute for secondary batteries. The type of cathode material has enormous implications for the performance of AZIBs. Organics can act as a suitable cathode for AZIBs because of their green, adjustable structure and good stability. However, developing promising organics with high performance is still an important challenge. Here, an organic material 8,21-dihydronaphtho[2,3-a]naphtha[2′,3′:7,8]quinoxalino[2,3-i]phenazine-5,11,16,22-tetraone (DADB) was synthesized and explored as a cathode for AZIBs. Benefiting from the affluent active sites and the expanded conjugated structure, the DADB electrode rendered splendid rate capability (71 mA h g–1 under 5 A g–1) and outstanding cycle lifespan (87% retention over 6000 cycles under 10 A g–1). Moreover, ex situ characterizations proved that CN and CO bonds were the electrochemical redox centers for storage of Zn2+. Additionally, the DADB electrode also exhibited excellent electrochemical performance in a gel electrolyte (134 mA h g–1 under 0.05 A g–1). This research offered a mentality for designing high-performance organic cathodes of AZIBs.

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