In Situ Generated Zwitterionic Interface for Reversible Zn Anodes

Aqueous zinc ion batteries possess the merits of low cost, high safety, sustainability, and scalable production. However, the thorny issues of parasitic side reactions and zinc dendrite growth hinder their practical applications. Herein, an in situ generated polyzwitterionic polymeric interface {poly[3-(1-vinyl-3-imidazolio)propanesulfonate]} is constructed on the Zn anode through a simple yet efficient polymerization strategy. The designed polymeric interface not only accelerates the Zn²⁺ ion transport, repulses free SO₄^2– anions, and facilitates the desolvation of Zn²⁺ ions but also replenishes Zn²⁺ ions at the electrode–electrolyte interface to mitigate the concentration gradient. Benefiting from such a unique design, Zn–Zn symmetric cells represent stable Zn plating/stripping for 7400 h at 0.5 mA cm^–2. Moreover, the Zn–Cu asymmetric cells could deliver steady plating/stripping exceeding 6200 cycles with an average Coulombic efficiency of 99.60. This work highlights the potential of coordination interphase engineering in ensuring the stability of Zn anodes.