Polydentate Ligand‐Induced Surface Reconstruction of MIL‐88A Reinforced Gel Electrolytes for Highly Reversible Zinc Batteries via Ion Rectification and Charge Redistribution
Zeyu Yan, Fusheng Luo, Song Yang, Qing Wu, Jinlong Zhang, Xiude Liu, Jun Huang, Yiwang Chen
Abstract
Abstract Dendrite growth and irreversible side reactions caused by inhomogeneous ionic/electric field distributions at Zn anodes in conventional gel electrolytes, combined with their inherent ion transport constraints, seriously limit the electrochemical performance and cycling stability of aqueous Zn ion batteries (ZIBs). Herein, a synergistic ion rectification/charge redistribution strategy is established by incorporating phytic acid (PA)‐phosphorylated MIL‐88A metal–organic frameworks into the polyacrylamide (PAM) gel electrolyte for building highly reversible Zn anodes. This unique strategy leverages the phosphate groups on PA as zincophilic sites within the gel electrolyte for promoting rapid ion migration, while the porous MIL‐88A dissipates charge accumulation caused by ion concentration differences and adjust the micro‐space charge distribution for ensuring uniform electric field distribution and effectively suppressing Zn dendrite formation, thereby enabling highly reversible ZIBs. As a result, this synergistic ion rectification/charge redistribution strategy achieves the high Zn 2+ ions transference number of 0.66, the excellent coulombic efficiency of Zn//Cu cell of 99.7%, the outstanding cycle life of Zn//Zn cell exceeding 3600 h and a high cumulative capacity of 2200 mAh cm −2 , providing a promising solution for the design of highly reversible Zn‐based energy storage devices.