Glucose-Induced Interfacial V/O Redox Reconstruction for Constructing Water-Stable Vanadium Oxide Positive Electrodes for Aqueous Zinc-Ion Batteries

Abstract

Vanadium oxides are regarded as promising positive electrode materials for aqueous zinc-ion batteries (AZIBs) due to their high theoretical capacity and multielectron redox activity. However, their narrow interlayer spacing and susceptibility to surface water-induced erosion and vanadium dissolution in aqueous electrolytes lead to restricted cycling stability, thereby limiting their practical applications. Herein, a glucose-assisted one-step hydrothermal strategy is employed to perform interfacial regulation on manganese-intercalated vanadium oxide (G-MVO), aiming to suppress vanadium dissolution and enhance the low-potential V4+/V3+ redox activity. The glucose treatment of manganese-intercalated vanadium oxide (MVO) induces a reconstruction of the V/O coordination environment on the surface. Specifically, the increased V4+ content and reduced surface-bound water suppress dissolution in the aqueous electrolyte and stabilize the electrode/electrolyte interface. Electrochemical tests demonstrate that the glucose treatment enhances the V4+/V3+ redox process in the low-potential region, resulting in a high specific capacity of 536.4 mAh g–1 at 0.1 A g–1. Simultaneously, the interfacial redox reconstruction effectively inhibits vanadium dissolution and improves cycling stability, maintaining a capacity of 237 mAh g–1 after 3000 cycles at 5 A g–1. This work clarifies how glucose treatment regulates the interfacial chemistry of vanadium oxide positive electrodes and provides a practical strategy for developing durable vanadium-based positive electrodes for AZIBs.