Self-Assembled Multifunctional Monomolecular Interface Enables Highly Reversible Aqueous Zinc-Metal Batteries

Aqueous zinc-ion batteries face significant challenges due to dendrite formation and water-induced side reactions. To address these issues, we are developing fluorinated multifunctional self-assembled monolayers (SAMs) on zinc anodes using (3,3,3-trifluoropropyl)trimethoxysilane. These SAMs enhance the transport kinetics of Zn^{2 +} ions through ion-dipole interactions, thereby contributes to suppressed the formation of zinc dendrites under high current density. Additionally, the hydrophobic and electronegative properties of SAMs repel water molecules and anions, thereby alleviates hydrogen evolution and corrosion. The modified zinc anode demonstrates superior electrochemical performance, enabling symmetric cells to operate stably for over 1570 h at a current density of 5 mA cm^-2 and an areal capacity of 2.5 mAh cm^-2, as well as achieving a sixfold increase in cycling stability at 10 mA cm^-2 compared to unmodified zinc anodes. Furthermore, asymmetric cells exhibit a coulombic efficiency of 99.69% sustained over 850 cycles. Full cells incorporating various cathode materials show improved rate capabilities and exceptional longevity, exemplified by Zn//I₂ cells maintaining 86.3% capacity retention after 30 000 cycles. This interface engineering approach promotes uniform zinc plating and stripping while enhancing interfacial stability, offering a molecular-level protective strategy for advancing high-performance zinc metal batteries.