Abstract
CO oxidation on has been studied using density functional theory calculations. Four possible reaction mechanisms were investigated and the most feasible one is the following: (i) the O at the bridge site of reacts with CO on the coordinatively unsaturated site (CUS) with a negligible barrier; (ii) adsorbs on the bridge site and then interacts with CO on the CUS to form an OO-CO complex; (iii) the bond of O-OCO breaks to produce with a small barrier (0.01 eV). The CO oxidation mechanisms on metals and metal oxides are rationalized by a simple model: The O-surface bonding determines the reactivity on surfaces; it also determines whether the atomic or molecular mechanism is preferred. The reactivity on metal oxides is further found to be related to the 3rd ionization energy of the metal atom.
- Received 19 April 2004
DOI:https://doi.org/10.1103/PhysRevLett.93.106104
©2004 American Physical Society