Artículo de revista
Electron beam-induced structural transformations of MoO3 and MoO32x crystalline nanostructures
Fecha
2012Registro en:
J Nanopart Res (2012) 14:679
DOI 10.1007/s11051-011-0679-2
Autor
Díaz Droguett, Donovan Enrique
Zúñiga Páez, Alejandro
Solorzano, G.
Fuenzalida, V. M.
Institución
Resumen
Electron beam-induced damage and structural
changes in MoO3 and MoO3-x single crystalline
nanostructures were revealed by in situ transmission
electron microscopy (TEM) examination (at 200 kV)
after few minutes of concentrating the electron beam
onto small areas (diameters between 25 and 200 nm)
of the samples. The damage was evaluated recording
TEM images, while the structural changes were
revealed acquiring selected area electron diffraction
patterns and high resolution transmission electron
microscopy (HRTEM) images after different irradiation
times. The as-received nanostructures of orthorhombic
MoO3 were transformed to a Magne´li’s phase
of the oxide (c-Mo4O11) after *10 min of electron
beam irradiation. The oxygen loss from the oxide
promoted structural changes. HRTEM observations
showed that, in the first stage of the reduction, oxygen
vacancies generated by the electron beam are accommodated
by forming crystallographic shear planes. At
a later stage of the reduction process, a polycrystalline
structure was developed with highly oxygen-deficient
grains. The structural changes can be attributed to the
local heating of the irradiated zone combined with
radiolysis.