The adsorption and thermal reactivity of NO and CO over an Ir(211) surface were studied using x-ray photoelectron spectroscopy, infrared reflection absorption spectroscopy, and temperature-programed desorption. NO adsorbed on the atop site of the (111) terrace and the bridge site of the (100) step at 273 K. In contrast, CO adsorbed only on the atop site at 273 K, initially on the (111) terrace and then on the (100) step. Both atop NO and bridge NO decomposed to N2 through the recombination of atomic nitrogen, indicating that the Ir(211) surface provides high NO dissociation activity. When NO and CO were coadsorbed, the preadsorption of atop CO on the terrace sites selectively inhibited the adsorption of atop NO on the terrace sites, while preadsorption of atop CO on the step sites significantly inhibited the adsorption of bridge NO on the step sites. These results indicate that NO may be selectively reduced by CO in the presence of O2 when Ir(211) is used as the catalyst.
|Number of pages||4|
|Journal||Journal of Vacuum Science and Technology A: Vacuum, Surfaces and Films|
|Publication status||Published - 2007|
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces and Interfaces
- Surfaces, Coatings and Films