Long-Chain Molecule Reconstruction of Novel Solvation Structure to Stabilize Zinc Metal Anode

In aqueous zinc ion batteries, the electrolyte is not only the medium for ion transport, but also directly affects the interface integrity of Zn anode. The active H₂O molecules in the solvation structure are prone to undergo the hydrogen evolution reaction on the Zn sheet, and induce the evolution of by-products such as basic zinc salts. Therefore, triethylene glycol diacetate (TGD) with unique long-chain characteristics and rich oxygen-containing functional groups was used as an electrolyte additive to reconstruct the solvation structure. TGD can reduce the erosion of H₂O molecules on the Zn anode, effectively homogenize the electric field distribution, and increase the Coulombic efficiency of the Zn//Cu half-cell to 95.8%. The Zn//Zn symmetric cell can realize an ultra-long cycle life of 8000 h. Besides, the capacity retention rate of Zn//I₂ still reached 91% after 6000 cycles at 1 A g^-1. This study offers a new method for preparing a high-durability and reversible Zn anode by regulating the solvation structure through electrolyte additives.