Rearrangement of H-bonds network of solvation structure via a zincophilic polyol-type surfactant to stabilize zinc anode in aqueous zinc-ion batteries

Aqueous zinc-ion batteries (AZIBs) are promising large-scale energy storage devices due to their costeffectiveness and high safety. However, the rampant dendrite growth and notorious side reactions resulting from the decomposition of active water molecules hinder its practical application. Herein, the zincophilic polyoltype surfactant of alkyl polyglycoside (APG) is introduced to induce the rearrangement of the H-bonds network to diminish the free water activity, facilitating the zinc-ion solvation structure transition from [Zn2+(H2O)6 & sdot;SO42-] (solvent separated ion pair, SSIP) to [Zn2+(H2O)5 & sdot;OSO32-] (contact ion pair, CIP) with less Zn2+-solvated H2O. Meanwhile, the APG molecular preferentially adsorb on the Zn surface to form a dehydrated layer, which can suppress the hydrogen evolution reaction (HER) and hinder the two-dimensional (2D) diffusion of Zn2+ ions. Consequently, the Zn//Zn symmetric cell using our designed electrolyte demonstrates an ultralong cycle life of 5250 h at 1.0 mA cm-2/1.0 mAh cm-2. Furthermore, the as-prepared Zn//Na2V6O16 & sdot;3H2O full cell also delivers a high-capacity retention rate of 80.8% even after 1000 cycles at 2.0 A g-1, superior to that of the full cell using pure ZnSO4 electrolyte. This study offers an effective strategy to modulate the cation solvation structure by rearranging the H-bonds network for a highly reversible Zn anode.