Polydopamine Interfacial Regulation of Silver-Based Lithium Metal Anodes

Practical application of lithium metal batteries is hindered by uncontrolled dendrite growth and severe volume fluctuations. While silver current collectors offer intrinsic lithiophilicity, they face interfacial instability at high current densities. In this study, a polydopamine functionalized interface is constructed on silver foil via an in situ self-polymerization strategy. Distinct from conventional physical coatings, robust Ag–O/N coordination bonds form between PDA functional groups and the substrate, fundamentally reconstructing the interfacial electronic state. This molecular-level design establishes a triple-synergistic mechanism of charge homogenization (Fig. 1), stress buffering, and SEI stabilization. Consequently, Ag@PDA electrodes demonstrate a high Coulombic efficiency of 98.9% over 250 cycles, while symmetric cells exhibit stable operation for over 700 h with a low overpotential of about 21 mV. Furthermore, full cells paired with NCM811 cathodes deliver a stable capacity of 128 mAh g −1 at 2 C. This strategy effectively resolves the trade-off between lithiophilicity and interfacial stability, providing an innovative approach for high-performance lithium metal batteries.