A Hydrophobic and Zincophilic Interfacial Nanofilm as a Protective Layer for Stable Zn Anodes

The Zn metal anode has emerged as a promising contender for aqueous batteries. However, challenges such as H2 evolution and Zn dendrite formation have hindered the attainment of satisfactory cycling longevity. In this context, a hydrophobic and zincophilic interfacial nanofilm (HZF) is successfully developed and demonstrated as a protective layer for stabilizing Zn anodes. The HZF nanofilm, characterized by its uniformly distributed zincophilic groups, actively participates in the interfacial solvated structure of Zn2+ ions, thereby modulating the uniform deposition of Zn2+ flux onto Zn anodes and curtailing the deprotonation of solvated water molecules. Concurrently, the exposed hydrophobic surfactant within the nanofilm effectively acts as a barrier, preventing direct contact between water and the Zn anode. As a result, the Zn anode coated with the HZF nanofilm achieves stable and reversible Zn plating/stripping behavior. This is evidenced by the extended cycling lifespan of over 300 h at a discharge capacity of 10 mAh cm-2, with a deep discharge of 67% Zn utilization. A hydrophobic and zincophilic interfacial nanofilm is developed as a protective layer for Zn anodes. The nanofilm not only exhibits favorable interaction with Zn2+ ions, aiding in their uniform deposition, but also serves as a barrier to isolate water from the electrode. This endows the Zn anode with highly stable and reversible Zn plating and stripping behavior.image