N, O Co-doped porous carbon host with interconnected reaction microenvironments for long-life zinc-iodine batteries

• Key Words:ZN-I-2 BATTERY; PERFORMANCE
• Abstract:High energy density, intrinsic safety, and eco-friendliness of aqueous zinc-iodine (Zn-I2) batteries are hindered by the shuttle effect and sluggish iodine redox kinetics. These limitations result in the formation of highly soluble triiodide (I-3 ) intermediates, which adversely affect energy density and cycle life. To address these issues, we designed N, O co-doped porous carbon with interconnected microchannels (N/O-PC) to create abundant catalytic sites and a locally strong adsorption microenvironment for the iodine reduction reaction (IRR). The unique structure of N/O-PC facilitates electrolyte penetration and enhances iodine fixation and loading, effectively inhibiting the formation and shuttling of I-3 . Leveraging this favorable microenvironment, the battery exhibits exceptional cycling stability with a high capacitance retention rate after 65,000 cycles at 10 A g-1. In situ characterization and theoretical calculations confirm that N/O dopants serve as active centers promoting the chemical immobilization and catalytic conversion of polyiodides. This work integrates physical adsorption and catalytic conversion to construct a host material, offering a novel strategy for developing a powerful Zn-I2 batteries.
• Volume:517
• Issue:
• Translation or Not:no