Bilayered Nanostructured V2O5· nH2O for Metal Batteries.

Bilayered V2O5· nH2O prepared by sol-gel synthesis is generally assumed amorphous due to lack of long-range structural order. However, at the nanoscale, a well-organized repetition of bilayers is found and thus V2O5· nH2O can be considered a nanostructured material. Synthesis route affects the morphological and structural characteristics of V2O5· nH2O and, depending on the drying method used, xerogel and aerogel are obtained. The reduced structural order, the large interlayer space and the short diffusion length that this class of material offer are the key factors that allow V2O5· nH2O to reversibly host cations that are different in charge and dimensions. These properties make bilayered V2O5· nH2O materials almost unique for the wide range of applicability in metal batteries. Herein, a panoramic of the most common V2O5· nH2O synthesis methods and the peculiar characteristics of this material is given. A survey of the most important findings on the use of bilayered V2O5· nH2O for metal batteries is reported focusing on Li-, Na- and Mg-batteries. The increased number of publications recently divulgated confirms the renewed interest on V2O5· nH2O for energy storage and thus an updated rationalization of the findings can be helpful to guide further technological development and research activity in the field. [ABSTRACT FROM AUTHOR]