Regulating amorphous structure and mechanical strength induce enhanced interface chemistry toward long-life rechargeable aqueous Zn ion batteries

The effective optimization of Zn anode/protective layer interface stability, underpinned by an in-depth exploration of durable protection mechanisms, is crucial for developing artificial protective layers in high-performance aqueous Zn-ion batteries (AZIBs). In this work, we present a self-regulating, continuous and dense amorphous Al2O3-x-2 layer (referred to as A-Al2O3-x-2 layer) with exceptional mechanical strength, achieved through core process control. Spectroscopic and theoretical studies reveal that the amorphous structure of Al2O3-x-2, featuring stable oxygen vacancies, significantly enhances Zn2+ transfer kinetics and promotes uniform distribution. This unique structure guides controlled Zn deposition along the (002) plane, facilitating stable cycling. Furthermore, the excellent mechanical strength of A-Al2O3-x- 2@Zn is well maintained under extended cycling conditions, ensuring lasting interface integrity and durable protection. Under a challenging current density of 60 mA cm-2, the A-Al2O3-x-2@Zn symmetric cell demonstrates an impressive cycling lifespan of 9620 cycles. Furthermore, a full cell assembled with an A-Al2O3-x-2@Zn anode and an Al3+-doped MnO2 cathode exhibits substantially improved cycling performance with 100% capacity retention after 900 cycles at 1 A g-1, underscoring the importance of the synergistic effects between anode and cathode materials in achieving long-life AZIBs. This work provides valuable insights into designing durable protective layers for Zn anodes in aqueous Zn-ion batteries. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.