Highly Reversible Zn Metal Anodes Realized by Synergistically Enhancing Ion Migration Kinetics and Regulating Surface Energy

Abstract

AbstractThe Zn metal anode suffers from uncontrollable dendrite formation and intricate parasitic reactions that dramatically impede the commercialization of aqueous Zn metal batteries (AZMBs). This st proposes synergistic strategies for facilitating Zn2+ migration kinetics and regulating surface energy to achieve dendrite‐free Zn deposition and suppressing self‐corrosion by covering Zn anode with multifunctional covalent organic frameworks possessing sulfonate‐rich (SO3H) covalently‐tethered nanochannels (SCOFs). Benefiting from the vital interplay between SO3H and Zn2+, the SCOFs coatings form ample Zn2+ accelerated transport channels to extract Zn2+ from the electrolyte quickly, thereby promoting rapid desolvation of hydrated Zn2+, enhancing ion replenishment capability, and guaranteeing a steady stream of Zn2+ flux for endowing uniform and compact nucleation. Additionally, the zincophilic SCOFs significantly reduce the surface energy of the Zn (002) crystal plane, inducing preferentially crystallographic (002) orientation electroplating growth. Consequently, the SCOFs‐coated Zn anodes (SCOFs@Zn) demonstrate an excellent lifespan up to 4000 h at 5 mA cm−2, 1 mAh cm−2, and 3000 h at 5 mA cm−2, 2 mAh cm−2. Meanwhile, the full cell paired with the MnO2 cathode sustains remarkable reversibility within 1000 cycles. The synergistic approach to manipulating ion migration and surface energy provides new insights into developing highly stable AZMBs.