Functional Aerogel Driven Synchronous Modulation of Zn2+ Interfacial Migration Behavior and Electrolyte Microenvironment Enables Highly Reversible Zn Anodes

Uncontrolled dendrite growth and electrolyte-induced intricate parasitic reactions are two great challenges that hinder the commercial applications of aqueous zinc-ion batteries. Herein, a synchronous modulation strategy for Zn2+ interfacial migration behavior and electrolyte microenvironment is proposed by constructing a functional lanthanum hydroxide aerogel (LAG) interface layer on Zn anode surface. The in situ derivation of ion-conducting zinc hydroxide sulfate (ZHS) from LAG layer results in the spontaneous generation of a hierarchic interface layer during the plating process, where the high Zn2+ selectivity of the upper dense ZHS layer can limit SO42- migration and allow for fast Zn2+ interfacial migration kinetics, while the aerogel layer with well-defined nanochannels near the anode side can homogenize Zn2+ distribution, thus leading to the effective suppression of both dendrites and side reactions. Additionally, the pH microenvironment of the acidic electrolyte can be synchronously regulated by slightly soluble La(OH)(3) aerogel, further inhibiting electrolyte corrosion and HER. Consequently, the modified Zn anode delivers highly reversible Zn plating/stripping and low-voltage hysteresis, and the high areal-capacity Zn||MnO2 full cells demonstrate considerable electrochemical performances under high Zn utilization conditions. This functional aerogel-driven synchronous modulation strategy of Zn2+ migration behavior and electrolyte microenvironment provides new insight for stabilizing Zn metal anodes.