Morphology and Reactivity Evolution of HCP and FCC Ru Nanoparticles under CO Atmosphere

The morphology change of metallic nanoparticles induced by the interaction of gas molecules with nanoparticles is a very important surface chemistry process in heterogeneous catalysis. Here, we performed a thorough study to provide understanding of the influence of CO adsorption on theoretically established Ru nanoparticle models through an approach combining density functional theory, Wulff construction, and ab initio atomistic thermodynamics. The morphology of constructed Ru nanoparticles undergoes significant evolution upon changing CO coverage, exposed temperature, and pressure. The contribution from flat facets becomes more significant in equilibrium morphology of nanoparticles as the surface CO coverage increases. Such morphological evolution has a consequential impact on the inherited catalytic performance of Ru NPs, as they were applied into three probe catalytic reactions, CO direct dissociation, HCO formation, and CH3 hydrogenation. This study enriches the current knowledge of the ruthenium nanoparticle catalyst evolution under CO gaseous exposure and provides fundamental insights into the design of highly selective and active metallic nanoparticle catalysts.