Dynamic Bridging Ligand-Induced Regulated Coordination Chemistry for Highly Reversible Zn-Metal Anodes

The lifespan of aqueous Zn-ion batteries (AZIBs) is significantly affected by the Zn anode interfacial hydrogen evolution and uncontrolled dendrite growth. Although the development of versatile organic molecule additives presents a promising solution to mitigate these issues, the limited coordinated capability and uncontrolled electrochemical consumption during cycling remain challenging. Herein, a molecular dynamic bridging strategy is proposed by incorporating tris(2-pyridylmethyl)amine (TPA) into the electrolyte, enabling a highly reversible Zn anode. The TPA additive, featuring four-nitrogen-atom coordinated sites, acts as a molecular bridge that dynamically strengthens coordination with Zn²⁺ and concurrently attracts more OTf^- within the interface. This TPA-regulated interfacial modulation promotes Zn²⁺ transport and subsequent OTf^- decomposition, forming a robust and inorganic-rich solid electrolyte interphase, thereby significantly reducing side reactions and facilitating reversible Zn deposition. Consequently, the Zn anode with TPA electrolyte demonstrates an extended lifespan of over 4000 h in the symmetric cells and an impressive 99.84% Coulombic efficiency. Furthermore, Zn||PANI full cell runs over 4000 cycles with 81.9% capacity retention at 3 A g^-1. This work highlights the potential of a multi-coordination molecular dynamic bridging strategy to innovatively guide the design of advanced high-performance electrolyte additives for AZIBs.