Cobalt confined within nitrogen-doped porous carbon to enhance the redox kinetics and cycling stability of zinc-iodine batteries.

Despite the low cost and intrinsic safety, aqueous zinc-iodine (Zn-I2) batteries are limited by low capacity and sluggish redox kinetics. Herein, nitrogen-doped porous carbon hosting cobalt clusters (NPC-Co) is developed as an electrocatalytically active host to construct an iodine-loaded cathode (NPC-Co@I2). NPC-Co simultaneously promotes iodine redox conversion and enhances iodine adsorption. As a result, the Zn‖NPC-Co@I2 battery exhibits improved rate capability and cycling stability, delivering 109.3 mAh g-1 after 1000 cycles at 5C and retaining 97.6 mAh g-1 after 1500 cycles at 10C.