Interfacial Lewis Acid Chemistry Enabled by Mesoporous MOFs Toward High‐Performance Four‐Electron Zinc–Iodine Batteries

Abstract

ABSTRACT Zinc–iodine (4e − ‐Zn─I 2 ) batteries hold promise for grid‐scale energy storage, but their development is hampered by the instability of I + species and sluggish conversion kinetics. Here, we depart from conventional weak‐interaction catalyst strategies and establish a strong interfacial Lewis acid chemistry based on mesoporous Zr‐UiO‐66, achieving effective stabilization of I + species and efficient iodine conversion. Synchrotron characterizations reveal that mesopore engineering via a micelle pre‐coordination strategy generates abundant interfacial unsaturated Zr sites with intrinsic Lewis acidity and a reduced coordination number on the pore walls of mesoporous Zr‐UiO‐66. These Lewis acid sites strongly adsorb and stabilize ICl 2 − , and efficiently promote its conversion. Density functional theory calculations confirm the strong electronic coupling between Zr sites and iodine guests and the reduced energy barrier for I + /I 2 conversion. Concurrently, mesoporous channels facilitate mass transport, enabling seamless ion and electron transport. The resultant Zr‐Meso‐UiO‐66@I 2 cathode delivers a reversible capacity of 390 mAh g −1 at 10 C, approaching the theoretical four‐electron limit, along with unprecedented cycling stability with 89.7% capacity retention after 40,000 cycles at 100 C. The study offers a novel interfacial Lewis‐acid catalysis strategy for activating 4e − ‐Zn─I 2 batteries.