Biomimetic Anchor‐Capture Effect of Multidentate Electrolyte Additive for Ultrastable Aqueous Zinc Ion Batteries

Abstract

Abstract Uncontrolled dendrite growth and hydrogen evolution reactions on Zn anodes severely limit the practical application of aqueous zinc‐ion batteries. Electrolyte additive engineering offers a promising solution. This work proposes a bio‐inspired anchor‐capture effect using the multi‐dentate additive to simultaneously achieve robust interface construction and rapid Zn 2+ capture. Stevia (ST), a natural biomass extract featuring flexible multi‐dentate hydrophilic chain and rigid skeleton is selected as a proof of concept. Systematic characterizations and theoretical calculations verify the anchor‐capture effect of ST as trace electrolyte additive. On one hand, ST molecules preferentially adsorb and accumulate on the Zn anode surface, promoting the formation of homogeneous electrode‐electrolyte‐interface layer and reconstructing the interfacial hydrogen bonding network. On the other hand, the flexible multi‐dentate hydrophilic chains enhance the capture and immobilization of Zn 2+ , suppressing the 2D diffusion and guiding uniform deposition. Additionally, the strong binding energy between Zn 2+ and ST facilitates the desolvation process. As a result, Zn||Zn symmetrical cells exhibit an ultra‐long cycle lifespan (>8800 h at 0.5 mA cm −2 ), Zn||Cu asymmetrical cells perform exceptional reversibility (the average coulombic efficiency > 99.5% over 1200 cycles) and Zn||VO 2 full cells retain almost 100% capacity over 1000 cycles at 2 A g −1 . The biomimetic interface engineering strategy provides valuable insights for developing green electrolyte additives to stabilize Zn anodes.