Tailoring the Whole Deposition Process from Hydrated Zn2+ to Zn0 for Stable and Reversible Zn Anode.

Abstract

The practical application of aqueous zinc-ion batteries (ZIBs) indeed faces challenges primarily attributed to the inherent side reactions and dendrite growth associated with the Zn anode. In the present work, N-Methylmethanesulfonamide (NMS) is introduced to optimize the transfer, desolvation, and reduction of Zn²⁺, achieving highly stable and reversible Zn plating/stripping. The NMS molecule can substitute one H₂O molecule in the solvation structure of hydrated Zn²⁺ and be preferentially chemisorbed on the Zn surface to protect Zn anode against corrosion and hydrogen evolution reaction (HER), thereby suppressing byproducts formation. Additionally, a robust N-rich organic and inorganic (ZnS and ZnCO₃) hybrid solid electrolyte interphase is in situ generated on Zn anode due to the decomposition of NMS, resulting in enhanced Zn²⁺ transport kinetics and uniform Zn²⁺ deposition. Consequently, aqueous cells with the NMS achieve a long lifespan of 2300 h at 1 mA cm^-2 and 1 mAh cm^-2, high cumulative plated capacity of 3.25 Ah cm^-2, and excellent reversibility with an average coulombic efficiency (CE) of 99.7 % over 800 cycles.