Influence of Oxygen Adsorption on Surface Explosion Phenomena in the NO + CO/Pd(110) System
A. V. Matveev, A. A. Sametova, N. N. Bulgakov and V. V. Gorodetskii
G. K. Boreskov Institute of Catalysis, Siberian Branch of the Russian Academy of Sciences,
Pr. Akademika Lavrentyeva 5, Novosibirsk 630090 (Russia), E-mail: matveev@catalysis.nsk.su
Abstract
In the present work adsorption of NO and coadsorption of NO, CO and O2 has been investigated by means of thermal desorption spectroscopy (TDS) and temperature programmed reaction (TPR). Influence of adsorbed oxygen on morphology of Pd-nanoparticles as well as Pd(110) plane was studied by the theoretical method of interacting bonds (MIB). It has been shown that adsorption of atomic oxygen induces the morphology changes of Pd-nanocrystals and Pd(110) plane. By analysis of TPR spectra of desorbing N2 and CO2 for different NOads + COads coverages, we suggest an autocatalytic reaction in an "explosive" way. The addition of oxygen was found to inhibit the process of NO dissociation. Exposure of NO and CO on oxygen pre-adsorbed layer results in appearing of low-temperature peak of CO2 in TPR spectra at 265 K.
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