Rod-like nanocrystalline B-VO2: Hydrothermal synthesis, characterization and electrochemical properties

Rod-like nanocrystalline VO2(B) has been successfully synthesized via a simple hydrothermal process by using V2O5 as vanadium source and 4-butylaniline H3C–(CH2)3–(C6H4)–HH2 as reducing and structure directing agent. The compounds were analyzed through X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and UV–visible spectroscopy. The VO2(B) nanorods are up to several micrometers in length and about 80 nm in thickness with a large optical band gap of ∼2.709 eV. Thin films of VO2(B) nanorods deposited on ITO substrates were electrochemically characterized by cyclic voltammetry. The voltammograms show reversible redox behavior with charge–discharge cycling process corresponding to the reversible lithium intercalation/deintercalation into the crystal lattice. The average coulombic efficiency to this redox processes is upper 98% during the electrochemistry measurements.