Amine‐Functionalized MIL‐125 Separator and MOF‐Derived Carbon Host for High‐Performance Aqueous Zinc‐Iodine Batteries

Abstract

Abstract Aqueous zinc‐iodine batteries (AZIBs) have emerged as promising candidates for sustainable energy storage, benefiting from the earth's abundance and low redox potential of zinc. However, their practical deployment remains constrained by polyiodide shuttling, non‐uniform zinc deposition, and hydrogen evolution side reactions issues that collectively undermine capacity retention, Coulombic efficiency, and operational safety. Herein, a unified “three‐party synergistic” strategy is developed. First, a dip‐coated amine‐functionalized glass fiber (NH 2 ‐MIL‐125/GF) separator forms a polar, charged porous architecture that electrostatically adsorbs polyiodides while facilitating Zn 2+ transport. Second, a hierarchically porous TiO 2 /NPC host, derived from the same NH 2 ‐MIL‐125 precursor, features dual micro‐/mesopores and an ultrahigh specific surface area, enabling amorphous iodine encapsulation and improve redox kinetics. Third, interfacial engineering modulates Zn 2+ desolvation and promotes dense, uniform zinc plating. Full batteries (Zn||NH 2 ‐MIL‐125/GF||I 2 @TiO 2 /NPC) deliver a high reversible capacity of 215 mAh g −1 at 0.05 A g −1 , maintain 118 mAh g −1 at 2 A g −1 , and maintain 88% of the initial capacity after 10 000 cycles at 2 A g −1 , demonstrating exbatteriesent rate capability and long‐term cycling stability. This work not only pioneers the dual utilization of NH 2 ‐MIL‐125 for both separator engineering and iodine host design but also establishes a scalable framework for constructing high‐performance, long‐life aqueous metal‐halide batteries.