Interface Engineering by Hydrophilic and Zincophilic Aluminum Hydroxide Fluoride for Anode-Free Zinc Metal Batteries at Low Temperature

摘要

Anode-free batteriesgreatly promote overall energy density, but they requirean extremely high Coulombic efficiency (CE, >99.7%) to function normally.It becomes very challenging in aqueous batteries, because of water-relatedparasitic reactions and dendrite growth on Zn anodes. Herein, aluminumhydroxide fluoride coated on Cu foils (Cu@AOF) is used to realize the anodefreeaqueous batteries. AOF exhibits a high adsorption affinity to H_2O anda low diffusion energy barrier for Zn adatoms, promoting the desolvationprocess and surface migration. Meanwhile, the strong interaction betweenAOF and Zn~(2+) enables it to regulate the Zn~(2+) flux and benefit lateral growth.Then, the anode-free full cells of Cu@AOF‖Zn_(0.5)VO_2 exhibit a record-highcycle life of 2000 cycles at 1 A g~(?1) with an ultra-high average CE of 99.95%.More impressively, the full cell shows a long cycle life of 400 cycles with ahigh CE of 99.94% at ?20 ℃. This work provides sheds light on the rationalengineering of the electrode interfaces to obtain excellent performance at lowtemperatures.