An investigation was made of the reactivity of elemental carbon films, deposited from the vapour phase, with Fe and Ni substrates at room temperature. X-ray photo-electron spectroscopy measurements were presented as a method for evaluating kinetic reaction data. Carbon films were deposited onto various surface orientations representing geometries from a dense atom packing as in face-centred cubic (111) to an open surface structure as in face-centred cubic (100). During annealing experiments, several reactions were observed (carbon sub-surface diffusion, carbide formation, carbide decomposition and graphite ordering). These reactions and the respective kinetic parameters were analyzed and quantified by X-ray photo-electron spectroscopic measurements performed during annealing at 620 to 820K. The resulting activation barriers for carbon sub-surface diffusion were compared with calculated values by using density functional theory. The determined kinetic parameters were used to reproduce the thermal behavior of carbon films on nickel surfaces.

Carbon Reaction and Diffusion on Ni(111), Ni(100), and Fe(110) - Kinetic Parameters from X-Ray Photoelectron Spectroscopy and Density Functional Theory Analysis. A.Wiltner, C.Linsmeier, T.Jacob: Journal of Chemical Physics, 2008, 129[8], 084704