Suppression of Vanadium Oxide Dissolution via Cation Metathesis within a Coordination Supramolecular Network for Durable Aqueous Zn‐V₂O₅ Batteries

Abstract Aqueous zinc metal batteries (ZMBs) are a promising sustainable technology for large‐scale energy storage applications. However, the water is often associated with problematic parasitic reactions on both anode and cathode, leading to the low durability and reliability of ZMBs. Here, a multifunctional separator for the Zn‐V₂O₅ batteries by growing the coordination supramolecular network (CSN:Zn‐MBA, MBA = 2‐mercaptobenzoic acid) on the conventional non‐woven fabrics (NWF) is developed. CSN tends to form a stronger coordination bond as a softer cation, enabling a thermodynamically preferred Zn²⁺ to VO₂⁺ substitution in the network, leading to the formation of VO₂‐MBA interface, that strongly obstructs the VO₂(OH)₂⁻ penetration but simultaneously allows Zn²⁺ transfer. Moreover, Zn‐MBA molecules can adsorb the OTF⁻ and distribute the interfacial Zn²⁺ homogeneous, which facilitate a dendrite‐free Zn deposition. The Zn‐V₂O₅ cells with Zn‐MBA@NWF separator realize high capacity of 567 mAh g⁻¹ at 0.2 A g⁻¹, and excellent cyclability over 2000 cycles with capacity retention of 82.2% at 5 A g⁻¹. This work combines the original advantages of the template and new function of metals via cation metathesis within a CSN, provides a new strategy for inhibiting vanadium oxide dissolution.