High-Voltage Recyclable Organic Cathode Enabled by Heteroatomic Substitution for Aqueous Zinc-Ion Batteries

N-type organic compounds present themselves as promising high-capacity cathodes for aqueous Zn-ion batteries. However, a common challenge is their working voltages often falling below 1 V versus Zn2+/Zn. To bridge this gap, a high-voltage organic material is first developed, 5,6,11,12-tetraazanaphthacene (TANC), using a heteroatomic substitution strategy. TANC feature a large pi-conjugated plane enriched with pi-pi interactions, which not only enhancing structural stability but also boosting charge transfer kinetics. The TANC cathode is achieved from its dihydro precursor, denoted as 2H-TANC, via a facile in situ activation process within the battery itself. This electrochemical synthesis method is cost-effective and environmentally friendly compared to traditional chemical method. The cathode shows a record-high discharge voltage of 1.15 V (vs Zn2+/Zn) among n-type organic materials and maintains cycling stability over 47,500 cycles. Furthermore, spent TANC electrodes can be efficiently recycled via a simple extraction process. The work marks a significant step toward the development of high-voltage, affordable, and recyclable organic electrode materials, steering them to the forefront of future sustainable battery technologies. TANC is developed from the conventional PNZ skeleton through a heteroatomic substitution strategy. This modification yields notable improvements in discharge voltage, structural stability, and reaction kinetics. Conveniently, the TANC electrode can be synthesized directly within the battery and exhibits commendable recyclability. image