Synergetic Effect of Silicate Addition on Modifying Zincate Solvation and Regulating <scp>ZnO</scp> Formation Revealed by In Situ Raman Observation during Zn Discharging

Zn offers higher safety and lower material cost over Li, making it promising alternative anode material for secondary batteries and grid‐scale sustainable energy storage. Nonetheless, Zn anodes suffer from rapid interfacial degradation and surface passivation, limiting their long‐term reversibility. Here, potassium silicate is introduced as a functional electrolyte additive to modulate Zn interfacial chemistry and improve redox reversibility. At an optimal concentration of 0.1 m , silicate addition delays Zn passivation by 30% and significantly stabilizes the Zn | electrolyte interface. The coordination of silicate with zincate ions released during Zn discharge is unveiled by in situ Raman measurements, which governs the passivation dynamics and optimal silicate content. Further analyses reveal the modulation of the ZnO electronic structure via Si–O–Zn bridge bonding, which suppresses both crystal growth and particle aggregation of ZnO, eventually contributing to a highly porous and defective ZnO layer structure that can protect the activity of Zn anodes from quick passivation. These interfacial interactions are validated through theoretical calculations at the electrochemical solid–liquid interface. This study provided fundamental insight into additive‐induced interfacial regulation and offered a practical strategy for advancing the efficiency and stability of Zn‐based energy storage systems.