STRUCTURAL AND KINETIC-PROPERTIES OF NITRIC-OXIDE ADSORBED ON CLEAN MO(100) USING AUGER AND THERMAL-DESORPTION SPECTROSCOPIES

NO adsorbs onto Mo(100) via precursor state kinetics with an initial sticking probability of 1.0. The saturation NO coverage following room temperature and low temperature (80 K) adsorption is 0.75 and 1.0, respectively. N2 and O2 desorption are detected, indicating that a portion of the NO is dissociated on Mo(100). Coadsorbed oxygen from the NO decreases the N2 desorption activation energy. Two molecular NO desorption states are detected corresponding to desorption activation energies of 82 and 45 kJ/mol. No molecular NO desorption is detected following adsorption at 270 K for NO coverages less than 0.5 monolayers, which is taken to mean that all chemisorbed NO is dissociated. Molecular NO, however, does desorb at higher coverages. Evidence is presented for competition between dissociation and desorption following NO adsorption at 80 K. © 1990.