Separator functionalization enables high-performance zinc anode via ion-migration regulation and interfacial engineering

Aqueous zinc ion batteries (AZIBs) are promising energy storage devices. However, the formation of dendrites, hydrogen evolution, and corrosion reaction seriously affect their electrochemical performance. Herein, the synergistic effect of ion-migration regulation and interfacial engineering has been confirmed as the potential strategy by kaolin functionalized glass fiber separator (KL-GF) to alleviate these problems. The rapid and orderly Zn2+ migration was achieved to improve the transfer kinetics and induced uniform zinc deposition by more zinc-philic sites of KL-GF. Based on the interfacial engineering, the side reactions were effectively mitigated and crystal planes were regulated through KL-GF. The hydrophilicity of KL alleviated the corrosion and hydrogen evolution. Importantly, a preferential orientation of Zn (002) crystal plane by KL-GF was induced to further realize dendrite-free deposition by density functional theory (DFT) and X-ray diffraction (XRD) characterization. Hence, the Zn|KL-GF|MnO2 cell maintained a high discharge capacity of 96.8 mAh/g at 2 A/g after 1000 cycles. This work can provide guidance enabling high-performance zinc anode for AZIBs.