Electron delocalization orchestrated Zn²⁺ reduction chemistry enables highly reversible Zn metal anodes

Aqueous Zn metal batteries are limited by sluggish Zn²⁺ reduction kinetics and interfacial instability, while the mechanistic role of alcohol-based additives remains unclear. Here, we establish an electron delocalization orchestrated Zn²⁺ reduction chemistry using cyclic polyols with identical carbon numbers and functional group quantity but distinct topologies, including inositol, mannitol, and sorbitol. We show that electron delocalization across hydroxyl donor sites governs their effective utilization, thereby coupling Zn²⁺ solvation structure reconstruction with interfacial electrostatics regulation of the anodes. Among these, inositol exhibits a highly delocalized electronic structure and uniform charge distribution, which maximizes hydroxyl groups participation in Zn²⁺ coordination and hydrogen bond rearrangement. This coordinated environment lowers local charge density around Zn²⁺, accelerates charge transfer, and homogenizes the interfacial electric field, collectively promoting rapid and uniform Zn deposition. As a result, Zn||Zn cells sustain stable cycling for over 2700 h under harsh conditions, and Zn||Zn_xV₂O₅·nH₂O full cells deliver prolonged cycling stability. This work identifies electron delocalization as a molecular descriptor that governs Zn²⁺ reduction chemistry and establishes a general framework for designing highly reversible Zn metal anodes.