ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The angular and velocity distributions of desorbing N2, N2O, and NO molecules were studied in the decomposition of NO and also N2O on a palladium (110) surface by means of angle-resolved thermal desorption combined with cross-correlation time-of-flight techniques. The results were quite similar in both cases although the desorption of N 2, N2O, and NO concurrently peaked at 490 K in the NO decomposition and, in the N 2O decomposition, the desorption of N 2 and N2O peaked at 140 K. The desorption of N2O and NO showed a cosine angular distribution and a Maxwellian velocity distribution at the surface temperature. On the other hand, the N2 desorption collimated sharply at ±41°–43° off the surface normal in a plane along the [001] direction. Then the velocity distributions of N2 involved two hyperthermal components with the mean translational energy of 0.47 and 0.22 eV, respectively. A mechanism for the inclined N2 desorption was proposed to be due to a highly exothermic reaction of N2O(ad)→N2(g)+O(ad) and the strong repulsive force operative on the product N2 from the surface. © 1999 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.478733
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