Investigation of Nanocrystallized α-Fe<sub>2</sub>O<sub>3</sub> Prepared by a Precipitation Process
Langue
en
Article de revue
Ce document a été publié dans
Journal of Physical Chemistry C. 2008, vol. 112, n° 49, p. 19217-19223
American Chemical Society
Résumé en anglais
Nanocrystallized hematite α-Fe<sub>2</sub>O<sub>3</sub> was synthesized by a precipitation route followed by annealing at moderate temperature (400 °C). The final product was investigated by X-ray diffraction and scanning ...Lire la suite >
Nanocrystallized hematite α-Fe<sub>2</sub>O<sub>3</sub> was synthesized by a precipitation route followed by annealing at moderate temperature (400 °C). The final product was investigated by X-ray diffraction and scanning and transmission electron microscopies. The strong influence of the weak anisotropy of crystallites on the X-ray diffractogram profile is highlighted and discussed. From the Williamson and Hall plot, it appears indubitably that the short length of the crystallite shape corresponds to the <i>c</i> directions of the hexagonal unit cell. Thus, a platelet model was used to simulate crystallite morphology for the refinement process. The anisotropy of the crystallites in the present material is “moderate” since the ratio between large length and short length does not exceed 2. Nevertheless, this weak anisotropy has got a strong influence on the X-ray pattern.< Réduire
Mots clés en anglais
Crystallography
X-ray diffraction
Nanocrystals
Transmission electron microscopies
Origine
Importé de halUnités de recherche