Harnessing Dual Hydrogen Bonding and <i>Lewis</i> Acid–Base Interactions for Bio‐Inspired Symmetry‐Breaking Electrolytes in Aqueous Zinc‐Ion Batteries

Abstract

AbstractAqueous zinc‐ion batteries (ZIBs) offer a safe, cost‐effective alternative for large‐scale energy storage but are hindered by zinc dendrite growth, hydrogen evolution reactions (HER), and unstable electrode–electrolyte interfaces. These challenges largely stem from strong dipole interactions between symmetric water molecules and Zn2+, which destabilize the electric double layer (EDL) and trigger parasitic reactions. Drawing inspiration from biological systems that use asymmetric molecular interactions to regulate aqueous environments, we introduce isobutyramide (IAM) as a multifunctional electrolyte additive. IAM features both carbonyl and amide groups, enabling it to act as a dual‐site hydrogen bond donor and acceptor. This disrupts the hydrogen‐bonding network in water, reduces water activity, and suppresses HER. Additionally, IAM's lone pairs coordinate strongly with Zn2+, restructuring the solvation sheath and mitigating uncontrolled Zn2+ migration that leads to dendrite formation. This dual‐function, symmetry‐breaking strategy stabilizes the EDL, enhances Zn plating/stripping reversibility, and suppresses interfacial degradation. Electrochemical tests confirm IAM's efficacy: Zn||Cu cells exhibit 99.68% Coulombic efficiency over 1,000 cycles, Zn||Zn symmetric cells remain stable for over 4,250 h, and full‐cell Zn||V2O5 and Zn||I2 systems show significantly enhanced cycling performance. Zn||I2 pouch cells also demonstrate robust long‐term operation. This bio‐inspired approach offers a scalable path to high‐performance, practical aqueous ZIBs.