Stabilizing Zinc Anode through Ion Selection Sieving for Aqueous Zn-Ion Batteries

Abstract

Uncontrollable dendrite growth and corrosion induced by reactive water molecules and sulfate ions (SO 4 2−) seriously hindered the practical application of aqueous zinc ion batteries (AZIBs). Here we construct artificial solid electrolyte interfaces (SEIs) realized by sodium and calcium bentonite with a layered structure anchored to anodes (NB@Zn and CB@Zn). This artificial SEI layer functioning as a protective coating to isolate activated water molecules, provides high-speed transport channels for Zn 2+ , and serves as an ionic sieve to repel negatively charged anions while attracting positively charged cations. The theoretical results show that the bentonite electrodes exhibit a higher binding energy for Zn 2+ . This demonstrates that the bentonite protective layer enhances the Zn-ion deposition kinetics. Consequently, the NB@Zn//MnO 2 and CB@Zn//MnO 2 fullbattery capacities are 96.7 and 70.4 mAh g −1 at 2.0 A g −1 after 1000 cycles, respectively. This study aims to stabilize Zn anodes and improve the electrochemical performance of AZIBs by ion-selection sieving.