Ion-Coordination-Active UiO-66-SO 3 H Coating Stabilizes Zn Metal Anodes via Sulfonate-Directed Zn 2+ Desolvation

High Resolution Image Download MS PowerPoint Slide Aqueous zinc batteries are limited by dendrite growth and parasitic interfacial reactions that accelerate polarization and trigger early failure of Zn metal anodes. Here, a chemically active artificial interphase is engineered by coating Zn foil with a sulfonated Zr-based metal–organic framework (UiO-66-SO 3 H) using PVDF as a binder, converting a conventional surface coating into an ion-coordination-active interface in a 2 M ZnSO 4 electrolyte. In situ Raman spectroscopy indicates that the sulfonate-oxygen coordination sites transiently interact with Zn 2+ and promote partial desolvation, while density functional theory (DFT) calculations show more favorable Zn 2+ adsorption at sulfonate sites than on pristine UiO-66. These coupled effects reduce the nucleation overpotential to 31.1 mV and decrease charge-transfer resistance, enabling more uniform Zn plating/stripping as verified by operando optical microscopy and X-ray tomography. As a result, symmetric Zn||Zn cells cycle stably for >1000 h at 0.5 mA cm –2 (0.5 mAh cm –2 ) and >800 h at 3 mA cm –2 (3 mAh cm –2 ), and Zn||Cu cells deliver an average Coulombic efficiency of ∼99.6% over >500 cycles. Full cells paired with a NaVO cathode retain >1000 cycles at 6C with improved stability. This work establishes sulfonate-directed Zn 2+ coordination and interfacial desolvation within robust UiO-66 scaffolds as a practical strategy to extend the lifetime of aqueous Zn metal anodes.