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

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 Zn²⁺ 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^-1after 100 cycles in Zn||NH₄V₄O₁₀ cells and a capacity retention of 92.9%@ 2 A g^-1 after 700 cycles in Zn||δ-MnO₂ cells. This approach offers a universal interface regulation strategy using MMI to enhance the performance of AZIBs.