Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9594562 | Surface Science | 2005 | 11 Pages |
Abstract
We have, theoretically and experimentally, investigated the dissociation of methane on the terraces and steps of a Ni(1Â 1Â 1) surface. Using Density Functional Theory (DFT) total energy calculations combined with Ultra High Vacuum (UHV) experiments, we find that the steps exhibit a higher activity than the terraces. We have, furthermore, investigated how carbon and sulfur present on the surface will deactivate the steps, leaving only the terraces active. We find the intrinsic sticking probabilities of methane on the steps and terraces at 500Â K to be 2.8Â ÃÂ 10â7 for the steps and 2.1Â ÃÂ 10â9 for the terraces, in complete agreement with our calculated difference in activation energy of 17Â kJ/mol.
Related Topics
Physical Sciences and Engineering
Chemistry
Physical and Theoretical Chemistry
Authors
Frank Abild-Pedersen, Ole Lytken, Jakob Engbæk, Gunver Nielsen, Ib Chorkendorff, Jens K. Nørskov,