Accelerated Zn Ion Transport by Hydrogen-Bonded Organic Framework-Modified Separators for Aqueous Zinc-Ion Batteries

Rechargeable aqueous zinc-ion batteries (AZIBs) are safe and affordable energy storage devices. However, AZIBs face significant challenges such as zinc dendrite formation, electrode passivation, and corrosion. Hydrogen-bonded organic frameworks (HOFs), the crystalline porous materials self-assemble via intermolecular complementary hydrogen bonds, can enhance ion exchange rates and thereby improve battery performance. In this study, HOF-DAT is synthesized and introduced to modify glass fiber (GF) separators (HOF-GF). The HOF-GF separator enhances the reversibility of zinc electrochemistry during cycling, alleviating degradation associated with nonuniform metal growth. In Zn//Zn symmetric cells, stable operation is maintained for prolonged cycling at 1 mA cm −2 with an areal capacity of 1 mAh cm −2 . These cells also exhibit consistent performance under higher current densities, maintaining stable operation even at 5 mA cm −2 . Additionally, Zn//NVO batteries assembled with HOF-GF separators exhibit a high initial capacity of 430 mAh g⁻ 1 at 0.1 A g⁻ 1 , and improve capacities at different currents. By demonstrating a scalable separator engineering concept, this study advances zinc anode regulation while offering a viable pathway toward durable and economically competitive aqueous zinc-ion battery systems.