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

Abstract

AbstractAqueous 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.