Quartet Mechanism of Sulfhydryl and Imidazolyl Group Bidentate Coordination Induced Hydrophobic Interface Layers to Achieve Preferential Deposition of Zinc (101) Crystal Planes

ABSTRACT Aqueous zinc‐ion batteries (AZIBs) are recommended as promising energy storage systems; however, serious Zn dendrite growth and unexpected side reactions hinder their practical application. Herein, 2‐mercapto‐1‐methylimidazole (MMI) is introduced as a new additive to form a self‐assembled SEI layer, achieving dense crystal deposition and suppressing violent side reactions. The MMI achieves well‐regulated zinc deposition of (101) crystal planes and side reaction inhibition via a proposed quartet mechanism of “Dual Coordination‐Induced Adsorption‐Film Formation‐Water Resistance” through the unique bidentate coordination ability of the sulfhydryl group and the imidazolyl group. The increased desolvation activation energy and higher nucleation overpotential of Zn 2+ slow down its nucleation rate, promoting fine nucleation. The cycle life of Zn||Zn symmetric batteries with MMI is significantly extended from 290 to 2800 h at 1 mA cm −2 compared to the blank samples. Besides, the MMI‐contained AZIBs remarkably improve the rate performance and long‐term cycling stability in different cells, with a specific capacity of 203.8 mAh g −1 @ 0.2 A g −1 after 100 cycles in Zn||NH 4 V 4 O 10 cells and a capacity retention of 92.9%@ 2 A g −1 after 700 cycles in Zn||δ‐MnO 2 cells. This approach offers a universal interface regulation strategy using MMI to enhance the performance of AZIBs.