Vanadium-Containing Layered Materials as High-Performance Cathodes for Aqueous Zinc-Ion Batteries

The world is currently in the midst of a climate crises and many across the globe are competing to find new technologies to create clean, and effective ways of harnessing renewable energy sources. However, this energy needs to be stored and the current systems simply would not last. Zinc-ion batteries (ZIBs) with vanadium-containing cathodes are a recently arising technology providing a cheap, safe, and eco-friendly alternative to the current systems. Vanadium is a material that has long been used for electrochemical systems due to its large range of stable oxidation states. Most common is the vanadium oxide (V2O5) renowned for its open layered framework and manipulatable structure. However, this is not the only vanadium-containing material that is proposed for use in ZIBs. The vanadium family is comprised of four main sub-categories under which materials can be classified: vanadium oxides, vanadium phosphates, vanadates, and O-2-free vanadium compounds. This report delves into the specifics of each of these sub-families to further develop the understanding of their functionality by highlighting their structural and morphological characteristics, aptitude for modification, and the corresponding electrochemical properties. Through this investigation, the application of these materials in ZIB systems is highlighted and future development aims considered.