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 cost-effectiveness 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 polyol-type 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·SO42–] (solvent separated ion pair, SSIP) to [Zn2+(H2O)5·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//Na2V6O16·3H2O 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.