Multifunctional porous carbon strategy assisting high-performance aqueous zinc-iodine battery

Abstract

Despite its cost-effectiveness and intrinsic safety, the aqueous zinc-iodine battery is still struggling with the rapid performance degradation arising from the uneven deposition of the zinc anode and the dissolution of the iodine cathode. An effective solution of addressing the above issues simultaneously is urgently needed. Here we propose a strategy of using one porous carbon to modify the zinc anode and immobilize the iodine active materials. Zinc citrate-derived porous carbon is selected as a study model. The conductive porous carbon can not only greatly reduce the zinc nucleation barrier, and guide a uniform deposition of zinc ions, but also notably suppress the dissolution of iodine species and enhance the reaction kinetics. As a consequence, the optimized zinc-iodine battery exhibits capacity retention of 88.1% after 3000 cycles at 12C, finishing a cycle within 5 min.