Iron-based substrate anchored dendrite-free zinc coating for aqueous zinc-ion batteries

Intrinsically safe aqueous zinc ion batteries (AZIBs) are attractive for grid-level energy storage, however, its commercialization still faces the issues of dendrite growth, parasitic side reactions, and low zinc utilization of anode. Herein, we develop a stable Zn-plated Fe anode by electrodepositing zinc on iron foil. A bifunctional molecule, 3-mercapto-1-propanesulfonate (MPS), was employed to construct an MPS-derived assembled bridge interface (ABI) at the Fe Zn interface, where the thiol groups of MPS coordinate with Fe and Zn to form localized Fe S and Zn S interfacial linkages, strengthening the interfacial connection, while sulfonate groups regulate Zn 2+ distribution and nucleation. The ABI mitigates the interfacial instability arising from the large lattice mismatch between Fe and Zn and promotes homogeneous zinc deposition, thereby forming a high-performance Zn-MPS/Fe (ZMF) anode. Symmetric ZMF cells exhibit stable cycling performance, operating for 2800 h at 0.5 mA cm − 2 . ZMF//Cu half-cells demonstrate outstanding reversibility with only 44.0 mV polarization. This work presents a molecular-engineering strategy for constructing high-performance, low-cost Fe-supported Zn anodes.