Abstract
Metallic zinc (Zn) with high safety and low cost is an ideal anode for aqueous batteries, but suffers from water-induced side reactions and dendrite growth. Herein, we significantly stabilize the Zn anode in a non-concentrated aqueous zinc trifluoromethanesulfonate (Zn(OTF)2) electrolyte when 1,2-dimethoxyethane (DME) additive is used to simultaneously regulate the electrolyte structure and Zn interface chemistry. We find that the introduction of DME not only interrupts the original hydrogen-bond network of water but also creates a unique Zn2+-solvation structure with the co-participation of DME and OTF−, which restrains the water-induced parasitic reactions. The in-situ formation of an organic-inorganic hybrid ZnF2-ZnS-rich interphase on Zn derived by the decomposition of DME and OTF− can suppress water penetration onto Zn and homogenize Zn2+ plating. In addition, DME molecules preferentially adsorb on the Zn surface, preventing the random growth of Zn dendrites. This novel H2O+DME electrolyte enables Zn anodes to achieve unprecedented cycling stability (over 5000 h at 2.0 mA cm−2) and high reversibility (99.7% Coulombic efficiency over 800 cycles). The efficacy of DME additives is further demonstrated in Zn//V2O5•nH2O full batteries with both coin- and pouch-type configurations. This work will inspire the design of efficient electrolytes for stable aqueous batteries.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have