Tris-amido naphthoquinone: toward high-capacity and stable organic cathodes for aqueous zinc batteries

Abstract

The development of organic electrodes featuring a high density of redox units and enhanced stability is of great theoretical and practical importance for advancing energy storage technologies. In this work, we present tris-amido naphthoquinone (TANQ) as a cathode material for high-performance aqueous zinc–organic batteries (ZOBs), achieved through molecular extension via amide linkages. The material benefits from synergistic hydrogen-bonding networks and π–π stacking, which strengthen intermolecular interactions and effectively suppress dissolution. Owing to its high density of redox centers, TANQ undergoes reversible multi-electron redox reactions, giving a high specific capacity of 213 mAh g⁻¹ at 0.2 A g⁻¹, primarily via a Zn²⁺ storage mechanism. This high capacity enables TANQ to achieve a notable specific discharge energy of 140 Wh kg⁻¹ at 0.2 A g⁻¹. TANQ also exhibits outstanding rate capability (153 mAh g⁻¹ at 2 A g⁻¹) and long-term cycling stability, retaining 94% of its capacity after 700 cycles.