Structural regulation of VS4 cathodes for enhanced aqueous zinc-ion battery performance

Abstract VS 4 has garnered significant attentions in aqueous zinc ion batteries (AZIBs) due to its unique structural features and high theoretical capacity. Unfortunately, the volumetric changes and sluggish kinetics of VS 4 during the electrochemical process often lead to material degradation and structural collapse, thereby limiting the performance of AZIBs. To address these challenges, we propose a structural engineering strategy for VS 4 to regulate its microstructure through a simple hydrothermal method. This approach enhances the number of active sites and facilitates the diffusion of Zn 2+ ions, thereby improving the electrochemical performance of VS 4 in AZIBs. The AZIBs using VS 4 flower (F-VS 4 ) as the cathode material exhibit significantly enhanced electrochemical performance. The electrochemical reaction mechanism of F-VS 4 is further elucidated by ex-situ x-ray diffraction and x-ray photoelectron spectroscopy measurements. This work represents a significant step forward in the development of vanadium sulfide-based cathodes for AZIBs, offering a promising strategy to enhance their electrochemical performance and stability.