Multibranched poly (1,4-benzoquinone-1,2,4,5-tetramethylenediamine) and its carbon nanotube composites for aqueous zinc-ion battery cathode

Organic quinone cathode materials possess several advantages, such as excellent redox activity, facilitated structural modification, and potential hydrophilic surface, that makes them highly potential in the application of aqueous zinc-ion batteries (AZIBs). Especially, many efforts are devoted to quinone polymer cathodes to inhibit their dissolution in the electrolyte and improve the cycle performance. In this paper, we synthesize a branched quinone polymer poly (1,4-benzoquinone-1,2,4,5-tetramethylenediamine) (PQBT) as AZIBs cathode material, which exhibits favorable electrochemical performance and composite application. PQBT achieves the discharge specific capacity of 165.0 mAh g⁻¹ at the current density of 0.02 A g⁻¹. And at high current density of 0.1 A g⁻¹, PQBT can maintain a capacity retention rate of 67.6% after 1100 cycles. Furthermore, the in situ composite of the PQBT and carbon nanotubes (CNT) results in improved rate performance, especially in terms of capacity at high currents.