Electrochemical Induced V5S8/V2O5 Heterostructures Manipulate Redox Kinetics for Aqueous Zinc-Ion Batteries

Abstract

Vanadium-based cathode materials have appealed comprehensive attention for zinc ion storage due to the enrich active sites and high specific capacities, yet the redox kinetics are limited by low intrinsic electronic conductivity and strong electrostatic interactions between zinc ions and host frameworks. Here we utilized the water/air sensitive properties of sulfides to construct a V5S8/V2O5 heterostructure through a facile electrochemical strategy. Analysis reveals that the heterointerface with built-in electric field could effectively facilitate charge carrier mobility and electrochemical activity, thus manipulating redox kinetics of the electrode. Moreover, benefiting from the high electronic conductivity of vanadium sulfides and high structural stability of vanadium oxides, the V5S8/V2O5 electrode achieves a superior capacity of 465 mA h g-1 at 0.1 A g-1 and capacity retention of 90.9% after 3000 cycles at 5 A g-1. The proposed in-situ electrochemical induced strategy also demonstrates strong applicability for fabricating VS4/VO2 heterostructure with excellent electrochemical properties. This work elucidates the key role of heterointerfaces in optimizing kinetics and establishes a universal design principle for high performance cathodes.