Translational energy of desorbing product and kinetic change at steady state in carbon monoxide oxidation on platinum(557)

Velocity distributions of desorbing product CO2 were studied in the CO oxid ation on Pt(557) over a wide range of surface temperatures, in both the act ive and inhibited regions at the steady state. The translational energy of CO2 in the active region, where the reaction is in a first order with respe ct to CO, is very high and it is insensitive to the surface temperature. It decreases sharply with increasing CO partial pressure in the boundary regi on. In the inhibited region, where the reaction is retarded by CO, the tran slational energy is relatively low and increases with increasing surface te mperature. (C) 1999 Elsevier Science B.V. All rights reserved.