Stability of ordered arrays of tiny supported platinum clusters exposed to gases

We aim at exploring the stability of ordered arrays of supported tiny Pt clusters under pre-catalytic conditions (i.e. exposed to low pressures of O2, CO, CO+O2 and increasing temperature). We already showed that Pt clusters organize on a template consisting of a thin alumina film on Ni3Al(111) with a density 3 or 9 times higher than palladium, depending on the growth conditions. These tailored ordered arrays open the way to explore the emerging topic of single-atom catalysis by using surface science techniques in order to understand the link between atomic-scale properties and catalytic performance. By combining GISAXS and GIXRD to in situ monitor the clusters' growth and (dis-)organization, we intend to i) follow the structural and morphological evolution of the clusters arrays and the substrate when exposed to gases and ii) determine the pressure and temperature limits up to which catalytic studies can be performed, while keeping a good spatial organization.