Comprehensive H2 O Molecules Regulation via Deep Eutectic Solvents for Ultra-Stable Zinc Metal Anode

Angew Chem Int Ed Engl. 2023 Feb 13;62(8):e202215552. doi: 10.1002/anie.202215552. Epub 2023 Jan 16.

Abstract

The corrosion, parasitic reactions, and aggravated dendrite growth severely restrict development of aqueous Zn metal batteries. Here, we report a novel strategy to break the hydrogen bond network between water molecules and construct the Zn(TFSI)2 -sulfolane-H2 O deep eutectic solvents. This strategy cuts off the transfer of protons/hydroxides and inhibits the activity of H2 O, as reflected in a much lower freezing point (<-80 °C), a significantly larger electrochemical stable window (>3 V), and suppressed evaporative water from electrolytes. Stable Zn plating/stripping for over 9600 h was obtained. Based on experimental characterizations and theoretical simulations, it has been proved that sulfolane can effectively regulate solvation shell and simultaneously build the multifunctional Zn-electrolyte interface. Moreover, the multi-layer homemade modular cell and 1.32 Ah pouch cell further confirm its prospect for practical application.

Keywords: Aqueous Zn Metal Batteries; Deep Eutectic Solvents; H2O Molecules Regulation; Hydrogen Bond Reconfiguration; Solvation Shell.