Temperature induced transition from hexagonal to circular pits in graphite oxidation by O<sub>2</sub>
Langue
en
Article de revue
Ce document a été publié dans
Applied Physics Letters. 2011, vol. 99, n° 4, p. 044102 (3 p.)
American Institute of Physics
Résumé en anglais
We report on an in-situ monitoring of graphite oxidation using a high temperature environmental scanning electron microscope. A morphological transition is clearly identified around 1040 K between hexagonal pits at low ...Lire la suite >
We report on an in-situ monitoring of graphite oxidation using a high temperature environmental scanning electron microscope. A morphological transition is clearly identified around 1040 K between hexagonal pits at low temperatures and circular pits at high temperatures, with apparently no change in the kinetic law. A kinetic Monte Carlo model allows rationalizing these findings in terms of the competitive oxidation of armchair and zig-zag edge sites and provides an estimate of the rate laws associated to these two events. Extended to three dimensions, the model also explains the "in-depth" transition between the stepwise hexagons and the hemispheres observed by atomic force microscopy.< Réduire
Mots clés en anglais
Atomic force microscopy
Graphite
High-temperature effects
Monte Carlo methods
Oxidation
Scanning electron microscopy
Solid-state phase transformations
Origine
Importé de halUnités de recherche