Effect of annealing and electrochemical properties of sol–gel dip coated nanocrystalline V2O5 thin films

Nanocrystalline vanadium pentoxide (V2O5) thin films were deposited on glass substrates by a simple and cost effective sol–gel dip coating method. The effect of annealing on microstructure and optical properties of V2O5 thin films were investigated. Formation of nanorods with the average diameter of 500–750nm after annealing is observed by scanning electron microscopy. X-ray diffractometry indicates that an orthorhombic structured thin film is transformed to β-V2O5 nanorods by subsequent annealing at 500°C. It was also confirmed that the growth of nanorods strongly correlates with annealing conditions; nanorod formation can be explained by surface diffusion phenomenon. The electrochemical performance of the V2O5 nanorods was investigated by cyclic voltammetry.