Easy access to VO2 nanostructures with controllable morphologies

Vanadium dioxide (VO2) has been widely investigated as electrochemical materials due to its reversible, ultrafast and multi-stimulus response phases transition. The morphological diversity of VO2 can trigger the fluctuant electrochemical property, thereby researchers devote to synthesize VO2 with controlled nanostructures. However, development of green solvothermal method to prepare the various morphologies of VO2 materials with water as solvent is still facing great challenges. Here we have synthesized a series of configurational VO2 including nanowires, nano-hollow spheres, nano-ellipsoids, nano-flowers, nano-spheres and nano-solid spheres by controlling surfactants/reducing agents in the presence of water. Both spherical and ellipsoidal VO2 are corresponding to D phase, other structures are consistent with B phase. Their specific surface areas range from 4 to 30 m2/g. The electrochemical performance indicates that spherical VO2 as an electrode has a higher surface Redox kinetic than that of VO2 nanostructures.