A High Capacity p-Type Organic Cathode Material for Aqueous Zinc Batteries.

P-type organic cathode materials typically exhibit high redox potentials and fast redox kinetics, presenting broad application prospects in aqueous zinc batteries (AZBs). However, most of the reported p-type organic cathode materials exhibit limited capacity (<100 mAh g), which is attributable to the low mass content ratio of oxidation-reduction active functional groups in these materials. Herein, we report a high-capacity p-type organic material, 5,12-dihydro-5,6,11,12-tetraazatetracene (DHTAT), for aqueous zinc batteries. Both experiments and calculation indicate the charge storage of DHTAT mainly involves the adsorption/desorption of ClO on the -NH- group. Benefitting from the high mass content ratio of the -NH- group in DHATA molecule, the DHATA electrode demonstrates a remarkable capacity of 224 mAh g at a current density of 50 mA g with a stable voltage of 1.12 V. Notably, after 5000 cycles at a high current density of 5 A g, DHTAT retains 73 % of its initial capacity, showing a promising cycling stability. In addition, DHTAT also has good low-temperature performance and can stably cycle at -40 °C for 4000 cycles at 1 A g, making it a competitive candidates cathode material for low-temperature batteries.