J. Phys. Colloques
Volume 49, Numéro C6, Novembre 198835th International Field Emission Symposium / 35éme Symposium International d'Emission de Champ
|Page(s)||C6-227 - C6-232|
J. Phys. Colloques 49 (1988) C6-227-C6-232
NITRIC OXIDE DISSOCIATION AND REDUCTION WITH HYDROGEN ON PLATINUM SURFACESP. LEERKAMP, R.M. WOLF et B.E. NIEUWENHUYS
Gorlaeus Laboratories, PO Box 9502, NL-2300 RA Leiden, The Netherlands
The surface structure dependence of the NO dissociation on Pt has been investigated using field electron microscopy (FEM). The first indication of dissociation is observed on rough kinked surfaces. This process starts around 300K, while at 370K a field emission pattern characteristic of an oxygen covered surface is found. If a NO covered field emitter is heated in the presence of hydrogen, the behavior until 350K is the same as observed for NO/Pt without H2. At 355K, however, a bright reaction zone is observed starting at (100), which shifts towards (110) and (111). Our interpretation of these results is that surfaces with a high concentration of kinks are most active for NO dissociation, followed by (100) and stepped (100) faces. These results are discussed in relation to literature data concerning NO dissociation on Pt.