Synergistic Stabilization of Zinc Anodes via Phenol Sulfonate Anion‐Rich Electric Double Layer and Robust SEI

ABSTRACT Electrolyte engineering extends Zinc anode cycling, yet how the solvation structure dynamically couples with electric double‐layer (EDL) chemistry during electrochemical operation remains poorly understood. Herein, a zinc phenolsulfonate (Zn(PS) ₂ )‐based hybrid electrolyte was constructed by introducing dimethyl sulfoxide (DMSO). In addition to reconstructing the electrolyte hydrogen‐bond grids, DMSO promotes the establishment of a PS ⁻ ‐reinforced solvation environment. This tailored solvation structure drives the formation of a PS ⁻ ‐rich interfacial EDL, in which PS ⁻ anions preferentially and uniformly adsorb on the Zn surface during dynamic electrochemical processes, thereby optimizing Zn ²⁺ diffusion. Meanwhile, the PS ⁻ ‐rich stern layer, together with the preferential decomposition of anions, facilitates in situ construction of a robust SEI. The synergistic effects of the EDL and SEI enable regulation of zinc deposition morphology, ensuring the zinc anode durability even under harsh conditions. The Zn||Zn symmetric cells exhibit a long cycling life of 1650 h at a DOD of 57%, along with excellent cycling performance across a broad temperature range from −30°C to 60°C. Furthermore, the Zn||I ₂ @AC cells exhibit a capacity retention of 97.66% after 44 000 cycles at 10 A g ⁻¹ . The multidimensional insights into interfacial electrochemistry in this work provide rational design principles for tailoring next‐generation aqueous batteries.