An electrochemically driven hybrid interphase enabling stable versatile zinc metal electrodes for aqueous zinc batteries

Abstract

Aqueous Zn ion batteries are advantageous in terms of safety and cost, while their sustainable applications are usually impeded by dendrite growth and interfacial side reactions. Here, we present the development of an electrochemically driven artificial solid-state electrolyte interphase, utilizing a metal surface coupling agent phosphate ester as a protective layer for Zn negative electrodes. Upon cycling, the protective layer in situ transforms into a hybrid phase enriched with well dispersed Zn₃(PO₄)₂ nanocrystals. This transformation ensures a uniform Zn²⁺ flux, effectively suppresses dendrite growth, and mitigates side reactions. In addition, such protective layer ensures Zn electrode stable plating/stripping performance for 1500 h at 10 mA cm⁻² and 1 mAh cm⁻², while pouch cells coupled with NaV₃O₈·1.5H₂O deliver ampere-hour level capacity. Beyond that, its robust adhesion and flexibility enable the Zn electrode to maintain good performance under a variety of harsh conditions. This approach provides valuable insights into the advancement of Zn metal batteries.