Self-assembly of super-hydrophobic and zincophilic surface monolayer for durable Zn anodes

The zinc (Zn) anode holds great promise for aqueous batteries due to its high volumetric capacity, low working potential, and natural abundance. However, the practical applications of Zn anodes are challenged by their poor interfacial stability in aqueous electrolyte, characterized by the notoriously mutual-promoted detrimental side reactions and uneven Zn deposition. These challenges arise primarily from sluggish Zn²⁺ transport and the interaction with active water molecules at the anode/electrolyte interface. Herein, we developed a super-hydrophobic and zincophilic surface by grafting a fluoroalkylsilane (FAS) monolayer onto Cu nanoclusters modified Zn anodes (denoted as FAS-Cu@Zn). The FAS monolayer (1.95 nm in thickness), fabricated via a facile and ultrafast self-assembly process, creates a robust and conformal coating that repels water molecules while facilitating Zn²⁺ transport, ensuring low interfacial polarization and uniform Zn deposition beneath the monolayer. This strategy suppresses parasitic reactions, and dendrite growth, significantly improving Zn anode performance. The FAS-Cu@Zn half cells demonstrated a Coulombic efficiency of 99.7% after 7500 cycles at 5 mA cm⁻². The NH₄V₄O₁₀ full cells with a low N/P ratio of 2.0 retained 84.3% capacity after 600 cycles at 1 A g⁻¹. These results showcase the potential of this scalable and cost-effective self-assembly strategy for durable, high-performance Zn-based energy storage systems.