Hydrothermal Synthesis And Characterization Of VO₂(B) And Zn₃(OH)₂V₂O₇·nH₂O

During the past few years, vanadium oxides based materials have attracted much attention due to their fascinating structures and electronic, optical, and magnetic properties, which are relevant to such diverse areas as lubrication, chemical sensor, catalysis, cathode materials in batteries, and electrochromic devices.Spindle like VO₂(B) was synthesized by a simple hydrothermal method. The structure and morphology of the as-synthesized VO₂(B) were characterized by X-ray diffraction(XRD), High-Resolution Transmission Electron Microscopy(HR-TEM), Scanning Electron Microscope(SEM), and Raman Spectra(RS). It is found that VO₂(B) nanospindles are composed of nanobelts with thickness of about 10 nm, preferring growth along [110] direction. Electrochemical properties of VO₂(B) as negative electrode of lithium ion battery was studied by conventional charge/discharge test, which shows steady platform near 2.1 V, suggesting it as an ideal candidate of cathode material for lithium ion battery.Well-crystallized zinc vanadium oxide hydroxide hydrate Zn₃(OH)₂V₂O₇·nH₂O nanobelts were successfully synthesized by a simple hydrothermal method. Transmission electron microscopy images reveal that those belts are several micrometers in length and 80-100 nm in width. The crispations of the as-synthesized nanobelts are probably due to their thickness. The products were shown to be crystallized by selected area electron diffraction characterization. The morphology of the products was tuned by simply changing the reaction temperature. Nanotubes were obtained at 140℃. Magnetic hysteresis measurements indicate that the as-synthesized nanobelts are of weak ferromagnetic property at room temperature.