Edge-electron induced ferrimagnetic effect to accelerate interfacial desolvation kinetics toward dendrite-free Zn metal batteries
Haifeng Yang, Fangqi Liu, Bixian Chen, Xiaomin Cheng, Qinghua Guan, Jing Dong, Teng Li, Lujie Jia, Wenbin Wang, Jing Zhang, Jiqiang Jia, Yongzheng Zhang, Canhuang Li, Yunjian Liu, Hongzhen Lin, Jian Wang
Abstract
Rechargeable aqueous zinc metal batteries (AZMBs) have garnered significant attention for large-scale energy storage. However, they are hindered by the sluggish Zn(H 2 O) 6 2+ desolvation kinetics, leading to uneven Zn deposition as well as side reactions of active water molecules for the formation of hydrogen evolution reaction (HER). Herein, high spin-state ferrimagnetic interphase of c spinel zinc ferrite (ZFO) has been pioneered to serve as artificial interphase on metallic Zn anode (ZFO@Zn). Specifically, high-spin Fe 3+ center enhances electron delocalization and the spinel crystal structure of ZFO layer facilitates the interfacial ion transfers, catalytically reducing the barriers of Zn 2+ desolvation and atom diffusion. Meanwhile, the micro-magnetic field self-motivates interfacial ion flux and separates the active molecules, enabling uniform Zn deposition without HER. The as-fabricated cell employed with ZFO@Zn achieved an impressive cumulative capacity exceeding 3500 mAh cm −2 at 30 mA cm −2 , demonstrating its remarkable kinetics and stability. The assembled vanadium-based full cell exhibits superior performance of 411.1 mAh g −1 at 10 A g −1 and maintained the capacity-retention of 90.7% after 3000 cycles at 5 A g −1 . Impressively, the large-areal pouch cell with ZFO@Zn anode stabilizes for 150 cycles, underscoring the potential of magnetic spinel materials for the commercialization of AZMBs.