A Tailored Water‐Based Binder with the Synergy of Hydrophobic Shielding and Anionic Regulation for Durable Zinc Powder Anodes

ABSTRACT Zinc powder (Zn‐P) is a promising anode material for aqueous zinc‐ion batteries owing to its high surface area, facile processability, and low cost. However, uncontrolled dendrite growth, parasitic corrosion, and structural failure during cycling severely impede their application. Here, we propose a water‐based binder, PAO (PAMPS ‐b ‐POMA), that integrates polyanionic and hydrophobic regulation to stabilize Zn‐P anodes. The anionic ‐SO ₃ ⁻ groups in PAMPS homogenize the interfacial electric field, facilitate Zn ²⁺ migration, and guide uniform Zn nucleation, while the long alkyl chains (‐C ₁₈ ) in POMA create a localized H ₂ O‐poor microenvironment that effectively suppress side reactions and corrosion. Moreover, the combined hydrophobic association, hydrogen bonding, and ionic bonding network endows the binder with mechanical robustness and volume adaptability. Benefiting from this synergistic regulation, the Zn‐P‐PAO anode achieves ultralong cycling lifespans of 3300 h at 1 mA cm ⁻² (1 mAh cm ⁻² ) and 1500 h at a 54% DOD _Zn (10 mAh cm ⁻² ) in Zn//Zn cells, and a high average coulombic efficiency of 99.86% (2000 h) in Zn//Cu cells. Full Zn‐P‐PAO//MnO ₂ batteries deliver a high rate capability (115.8 mAh g ⁻¹ at 20 C) and 84% capacity retention over 2000 cycles. This study develops an effective strategy for fabricating novel water‐based binders for highly reversible Zn‐P anodes.