Interaction of Platinum Nanoparticles Synthesized on Graphite with Nitrous Oxide

Abstract—

Heterogeneous catalytic reactions involving nitrous oxide (N₂O) are of great interest for medicine, technology, and ecology. The goal of this work is to determine the features of adsorption of N₂O molecules followed by their interaction with a catalytic system based on metal nanoparticles at room temperature. Scanning tunneling microscopy and spectroscopy, as well as Auger spectroscopy, have been employed to identify the results and products of the adsorption of nitrous oxide on the surface of individual Pt nanoparticles synthesized on highly oriented pyrolytic graphite. It has been shown that, at short exposures, oxygen atoms resulting from dissociative adsorption oxidize the surface of nanoparticles only near the platinum–graphite interface. As the exposure increases, the entire surface of the nanoparticles is covered with oxide. Thus, it has been shown that the adsorption properties of the surface of the platinum nanoparticles on graphite are not the same, and this fact provides the possibility to carry out different chemical reactions on different surface regions, thereby increasing the efficiency of the catalytic system as a whole.