Hydrogen/Electron Amphiphilic Bi‐Functional Water Molecular Inactivator‐Assisted Interface Stabilization in Highly Reversible Zn Metal Batteries

Abstract Continuous hydrogen‐bond‐network in aqueous electrolytes can lead to uncontrollable hydrogen transfer, and combining the interfacial parasitic electron consumption cause the side reaction in aqueous zinc metal batteries (AZMBs). Herein, hydrogen/electron amphiphilic bi‐functional 1,5‐Pentanediol (PD) molecule was introduced to stabilize the electrode/electrolyte interface. Stronger proton affinity of ‐OH in PD can break bulk‐H 2 O hydrogen‐bond‐network to inhibit the activity of water, and electron affinity can enhance electron acceptation capability, which ensures that PD is preferentially bound to electrode material over H 2 O. Besides, the participation of PD in the Zn 2+ solvation structure reduces water content at the solid–liquid interface and promotes uniform deposition process by optimizing Zn 2+ de‐solvation energy. Accordingly, dense and vertical zinc texture based on intrinsic steric hindrance effect of PD and formed SEI protective layer to induce stable Zinc anode‐electrolyte interface. Moreover, an organic–inorganic shielding water layer was formed at the cathode side to suppress vanadium dissolution in vanadium Oxide. Consequently, Zn//Zn symmetric cell could cycle for more than 5600 hours at 1 mAh cm −2 @1 mA cm −2 (more than 250 hours at 50 °C). Besides, the VO 2 and I 2 cathode all achieved stable cycling performance and former pouch cell could reach average capacity of 0.13 Ah.