Molybdenum trioxide nanostructures prepared by thermal oxidization of molybdenum

Molybdenum trioxide (MoO3) nanobelts and microballs were prepared by oxidization of molybdenum metal in an ambient atmosphere. Their lattice structures and morphologies were carefully studied by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM). The as-synthesized nanobelts and mircoballs are orthorhombic and monoclinic structured, respectively. The nanobelts are up to several hundred microns long, several hundred nanometers to several microns wide, with ratio of width to thickness between 5 and 10. HRTEM suggests the nanobelts grow along the [0 0 1] direction. The microballs are 3–10 μm in diameter. Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR) studies revealed the stretching vibration modes of Mo–O bonds as in α-MoO3 nanobelts. The possible growth mechanism of the nanobelts was discussed.