Suppressing Zinc Dendrites via Polyamine–Zn2+ Complexation in Weakly Acidic Electrolytes

Rechargeable zinc batteries, with a theoretical capacity of 820 mAh g -1 , provide advantages such as non-flammability, low cost, and environmental compatibility, but dendrite growth remains a major obstacle to long-term cycling.Here, we investigated the coordination behavior of diethylenetriamine (DETA) and triethylenetetramine (TETA) at pH 5.5 using proton nuclear magnetic resonance (¹H NMR) spectroscopy, operando optical microscopy, electrochemical measurements, and scanning electron microscopy.Both ligands reversibly interact with Zn 2+ , yet TETA exhibits superior ability to regulate deposition and suppress dendrite growth.This advantage is attributed to more stable Zn -TETA complexation.These findings emphasize the importance of coordination stability and interfacial regulation in additive design, providing practical guidance for improving the cycling performance of aqueous zinc batteries.