X-ray diffraction and Raman scattering studies on large-area array and nanobranched structure of 1D MoO₂nanorods

Abstract

One-dimensional (1D) MoO2 nanorods in the form of a large-area array and nanobranched structure were prepared by hot-filament metal–oxide vapour deposition at low and high pressures in atmospheric argon flows respectively. The x-ray diffraction (XRD) patterns of both as-synthesized samples show that the 1D MoO2 nanorods are monoclinic crystals in space group P 21/c. The Raman spectrum of the large-area array of 1D MoO2 nanorods appears to be the same as that of a two-dimensional (2D) MoO2 thin film. The Raman spectrum of the nanobranched structure of 1D MoO2 nanorods showed a downshift and asymmetric broadening of the Raman first-order TO peak when compared with the bulk (q = 0) mode. The Raman shift and broadening were attributed to phonon confinement effect in the 1D nanorods. The in situ Raman spectra of laser-induced oxidation of the nanobranched structure of 1D MoO2 nanorods demonstrate that they can be oxidized easily and more strongly than the 3D bulk MoO2 powder.

A hot-wire chemical vapor deposition (HWCVD) method for metal oxide and their alloy nanowire arrays

“…The XRD and Raman spectra ( Fig. 3c and d) confirm that the resulting nanotubular structures are of orthorhombic MoO 3 phase [23]. Earlier studies using tungsten filament also resulted in both tungsten oxide nanowires and nanotubes in the same experiments [15].…”

Adaptive Mo2N/MoS2/Ag Tribological Nanocomposite Coatings for Aerospace Applications

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