Cation-Selective Interface for Kinetically Enhanced Dendrite-Free Zn Anodes

Abstract

The Zn anode in aqueous zinc-ion batteries (AZIBs) is severely impeded by uncontrolled dendrite growth and promiscuous water-induced side reactions, resulting in low Coulombic efficiency (CE) and poor lifetime. Herein, a versatile Zn-based laponite (Zn–LT) interface is constructed for uniform and rapid Zn deposition for long-life AZIBs. The combined experimental results and theoretical simulations reveal that the abundant negatively charged channels in the Zn–LT layer permit cation penetration but shield anions to uniformly modulate Zn deposition. Moreover, Zn–LT not only acts as a desolvation layer to promote Zn deposition kinetics, but also effectively inhibit harmful Zn anode corrosion. Therefore, the functional Zn–LT interface enables the anode to deliver an average CE as high as 99.8% at 1 mA cm−2 and a long lifespan of >830 h at 10 mA cm−2 and 5 mA h cm−2. Moreover, the assembled MnO2||Zn–LT@Zn full battery exhibits prominent rate performance (123 mA h g−1 at 2 A g−1) and long-term cycling stability (80.4% capacity retention at 1 A g−1 after 700 cycles). Furthermore, the fabrication of this Zn-LT@Zn anode can be extended to rolling method, reflecting the industrial manufacturing potential.