Molecule-Adsorption-Induced Interface Micro-environment Regulating for Highly Stable Aqueous Zinc Ion Batteries

Irreversible Zn plating/stripping and uncontrollable interface micro-environment fluctuation induced by competitive side reactions in the electrical double layer limit the reversibility of aqueous zinc ion batteries (AZIBs). Here, we propose the molecule-adsorption-induced interface micro-environment regulating the electrical double layer (EDL) to stabilize Zn electrode/electrolyte interface electrochemistry by adding the Ellagic acid (Ea) electrolyte. Specially, the preferential adsorption of Ea on the Zn (002) facet creates a unique physical barrier interface on the Zn surface via the strong interaction between the Ea molecule and Zn anode. The Ea-molecule-induced adsorption layer could simultaneously act as a H₂O/H⁺-shielding interphase for suppressing side reactions and promoting homogeneous Zn²⁺ transport for compact Zn (002) deposition. As a result, Zn//Zn symmetric cells demonstrated outstanding lifespans that cycled over 300 h under the periodic changes of current densities from 1 to 20 mA cm^-2, and the Zn//Cu half cell delivered high Coulombic efficiency (99.53%) during 1000 cycles at 5 mA cm^-2 with 1 mAh cm^-2. Furthermore, the Zn//MnO₂ full cells preserved 72.9% capacity even after 2000 cycles at 2 A g^-1. This strategy opens a unique understanding of the relationship between electrical double layer regulation and highly efficient AZIBs.